**Item category:** Octafluoropropane or Refrigerant gas R 218

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.2, UN2424, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Octafluoropropane or Refrigerant gas R 218 2.2 UN2424 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Octafluoropropane or Refrigerant gas R 218 — Postal shipping restrictions by item category


**Item category:** Octanes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1262, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Octanes 3 UN1262 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Octanes — Postal shipping restrictions by item category


**Item category:** Octonal

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0496, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Octonal 1.1D UN0496 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Octonal — Postal shipping restrictions by item category


**Item category:** Octyl aldehydes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1191, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Octyl aldehydes 3 UN1191 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Octyl aldehydes — Postal shipping restrictions by item category


**Item category:** Octyltrichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1801, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Octyltrichlorosilane 8 UN1801 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Octyltrichlorosilane — Postal shipping restrictions by item category


**Item category:** odor-producing materials

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all domestic mail

**Conditions:** Any matter that is a source of an obnoxious odor is nonmailable

> Any matter that is a source of an obnoxious odor is nonmailable.

Source: <https://pe.usps.com/text/pub52/pub52c4_018.htm>

odor-producing materials — Postal shipping restrictions by item category


**Item category:** Oil gas, compressed

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN1071, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oil gas, compressed 2.3 UN1071 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oil gas, compressed — Postal shipping restrictions by item category


**Item category:** only per 343 3B Components, explosive train, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1B, UN0461, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> only per 343 3B Components, explosive train, n.o.s. 1.1B UN0461 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

only per 343 3B Components, explosive train, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organic peroxide type B, liquid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3111, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type B, liquid, temperature controlled 5.2 UN3111 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type B, liquid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type B, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3101, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type B, liquid 5.2 UN3101 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type B, liquid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type B, solid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3112, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type B, solid, temperature controlled 5.2 UN3112 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type B, solid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type B, solid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3102, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type B, solid 5.2 UN3102 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type B, solid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type C, liquid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3113, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type C, liquid, temperature controlled 5.2 UN3113 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type C, liquid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type C, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3103, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type C, liquid 5.2 UN3103 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type C, liquid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type C, solid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3114, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type C, solid, temperature controlled 5.2 UN3114 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type C, solid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type C, solid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3104, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type C, solid 5.2 UN3104 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type C, solid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type D, liquid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3115, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type D, liquid, temperature controlled 5.2 UN3115 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type D, liquid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type D, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3105, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type D, liquid 5.2 UN3105 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type D, liquid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type D, solid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3116, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type D, solid, temperature controlled 5.2 UN3116 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type D, solid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type D, solid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3106, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type D, solid 5.2 UN3106 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type D, solid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type E, liquid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3117, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type E, liquid, temperature controlled 5.2 UN3117 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type E, liquid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type E, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3107, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type E, liquid 5.2 UN3107 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type E, liquid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type E, solid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3118, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type E, solid, temperature controlled 5.2 UN3118 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type E, solid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type E, solid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3108, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type E, solid 5.2 UN3108 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type E, solid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type F, liquid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3119, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type F, liquid, temperature controlled 5.2 UN3119 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type F, liquid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type F, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3109, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type F, liquid 5.2 UN3109 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type F, liquid — Postal shipping restrictions by item category


**Item category:** Organic peroxide type F, solid, temperature controlled

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3120, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic peroxide type F, solid, temperature controlled 5.2 UN3120 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type F, solid, temperature controlled — Postal shipping restrictions by item category


**Item category:** Organic peroxide type F, solid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.2, UN3110, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Organic peroxide type F, solid 5.2 UN3110 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic peroxide type F, solid — Postal shipping restrictions by item category


**Item category:** Organic peroxides (Division 5.2) not qualifying as Limited Quantity

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Organic peroxides are nonmailable unless they qualify as Limited Quantity air or Limited Quantity surface

> Division 5.2, Organic Peroxides: Organic peroxides are nonmailable unless they qualify as Limited Quantity air or Limited Quantity surface.

Source: <https://pe.usps.com/text/pub52/pub52c3_024.htm>

Organic peroxides (Division 5.2) not qualifying as Limited Quantity — Postal shipping restrictions by item category

carrier, item_category, restriction_type, scope


**Item category:** Organic phosphate, mixed with compressed gas or Organic phosphate compound, mixed with compressed gas or Organic phosphorous compound, mixed with compressed gas

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, NA1955, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic phosphate, mixed with compressed gas or Organic phosphate compound, mixed with compressed gas or Organic phosphorous compound, mixed with compressed gas 2.3 NA1955 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic phosphate, mixed with compressed gas or Organic phosphate compound, mixed with compressed gas or Organic phosphorous compound, mixed with compressed gas — Postal shipping restrictions by item category


**Item category:** Organic pigments, self-heating

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN3313, packing group II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organic pigments, self-heating 4.2 UN3313 II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organic pigments, self-heating — Postal shipping restrictions by item category


**Item category:** Organoarsenic compound, liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3280, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organoarsenic compound, liquid, n.o.s. 6.1 UN3280 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organoarsenic compound, liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organoarsenic compound, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3465, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organoarsenic compound, solid, n.o.s. 6.1 UN3465 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organoarsenic compound, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organochlorine pesticide, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2996, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organochlorine pesticide, liquid, toxic 6.1 UN2996 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organochlorine pesticide, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Organochlorine pesticides liquid, flammable, toxic, flashpoint less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2762, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organochlorine pesticides liquid, flammable, toxic, flashpoint less than 23° C 3 UN2762 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organochlorine pesticides liquid, flammable, toxic, flashpoint less than 23° C — Postal shipping restrictions by item category


**Item category:** Organochlorine pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2995, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organochlorine pesticides, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN2995 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organochlorine pesticides, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Organochlorine pesticides, solid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2761, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organochlorine pesticides, solid, toxic 6.1 UN2761 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organochlorine pesticides, solid, toxic — Postal shipping restrictions by item category


**Item category:** Organometallic compound, toxic, liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3282, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic compound, toxic, liquid, n.o.s. 6.1 UN3282 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic compound, toxic, liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organometallic compound, toxic, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3467, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic compound, toxic, solid, n.o.s. 6.1 UN3467 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic compound, toxic, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organometallic substance, liquid, pyro9phoric, water-reactive

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN3394, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, liquid, pyro9phoric, water-reactive 4.2 UN3394 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, liquid, pyro9phoric, water-reactive — Postal shipping restrictions by item category


**Item category:** Organometallic substance, liquid, pyrophoric, water-reactive, flammable

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.3, UN3399, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, liquid, pyrophoric, water-reactive, flammable 4.3 UN3399 I, II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, liquid, pyrophoric, water-reactive, flammable — Postal shipping restrictions by item category


**Item category:** Organometallic substance, liquid, pyrophoric, water-reactive

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.3, UN3398, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, liquid, pyrophoric, water-reactive 4.3 UN3398 I, II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, liquid, pyrophoric, water-reactive — Postal shipping restrictions by item category


**Item category:** Organometallic substance, liquid, pyrophoric

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN3392, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, liquid, pyrophoric 4.2 UN3392 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, liquid, pyrophoric — Postal shipping restrictions by item category


**Item category:** Organometallic substance, solid, pyrophoric, water-reactive

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN3393, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, solid, pyrophoric, water-reactive 4.2 UN3393 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, solid, pyrophoric, water-reactive — Postal shipping restrictions by item category


**Item category:** Organometallic substance, solid, pyrophoric

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN3391, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, solid, pyrophoric 4.2 UN3391 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, solid, pyrophoric — Postal shipping restrictions by item category


**Item category:** Organometallic substance, solid, self heating

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN3400, packing group II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, solid, self heating 4.2 UN3400 II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, solid, self heating — Postal shipping restrictions by item category


**Item category:** Organometallic substance, solid, water-reactive, flammable

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.3, UN3396, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, solid, water-reactive, flammable 4.3 UN3396 I, II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, solid, water-reactive, flammable — Postal shipping restrictions by item category


**Item category:** Organometallic substance, solid, water-reactive, self-heating

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.3, UN3397, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, solid, water-reactive, self-heating 4.3 UN3397 I, II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, solid, water-reactive, self-heating — Postal shipping restrictions by item category


**Item category:** Organometallic substance, solid, water-reactive

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.3, UN3395, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organometallic substance, solid, water-reactive 4.3 UN3395 I, II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organometallic substance, solid, water-reactive — Postal shipping restrictions by item category


**Item category:** Organophosphorus compound, toxic, flammable, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3279, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus compound, toxic, flammable, n.o.s. 6.1 UN3279 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus compound, toxic, flammable, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organophosphorus compound, toxic, liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3278, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus compound, toxic, liquid, n.o.s. 6.1 UN3278 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus compound, toxic, liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organophosphorus compound, toxic, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3464, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus compound, toxic, solid, n.o.s. 6.1 UN3464 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus compound, toxic, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organophosphorus pesticides, liquid, flammable, toxic, flashpoint less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2784, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus pesticides, liquid, flammable, toxic, flashpoint less than 23° C 3 UN2784 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus pesticides, liquid, flammable, toxic, flashpoint less than 23° C — Postal shipping restrictions by item category


**Item category:** Organophosphorus pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3017, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus pesticides, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN3017 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus pesticides, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Organophosphorus pesticides, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3018, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus pesticides, liquid, toxic 6.1 UN3018 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus pesticides, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Organophosphorus pesticides, solid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2783, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organophosphorus pesticides, solid, toxic 6.1 UN2783 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organophosphorus pesticides, solid, toxic — Postal shipping restrictions by item category


**Item category:** Organotin compounds, liquid, n.o.s

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2788, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Organotin compounds, liquid, n.o.s 6.1 UN2788 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organotin compounds, liquid, n.o.s — Postal shipping restrictions by item category


**Item category:** Organotin compounds, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3146, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organotin compounds, solid, n.o.s. 6.1 UN3146 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organotin compounds, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Organotin pesticides, liquid, flammable, toxic, flashpoint less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2787, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organotin pesticides, liquid, flammable, toxic, flashpoint less than 23° C 3 UN2787 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organotin pesticides, liquid, flammable, toxic, flashpoint less than 23° C — Postal shipping restrictions by item category


**Item category:** Organotin pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3019, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organotin pesticides, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN3019 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organotin pesticides, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Organotin pesticides, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3020, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organotin pesticides, liquid, toxic 6.1 UN3020 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organotin pesticides, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Organotin pesticides, solid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2786, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Organotin pesticides, solid, toxic 6.1 UN2786 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Organotin pesticides, solid, toxic — Postal shipping restrictions by item category


**Item category:** Other regulated substances, liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, NA3082, packing group III; domestic mail air: 9C; domestic mail surface: 9C

> Other regulated substances, liquid, n.o.s. 9 NA3082 III 9C 9C

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Other regulated substances, liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Other regulated substances, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, NA3077, packing group III; domestic mail air: 9C; domestic mail surface: 9C

> Other regulated substances, solid, n.o.s. 9 NA3077 III 9C 9C

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Other regulated substances, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing liquid, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3098, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing liquid, corrosive, n.o.s. 5.1 UN3098 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing liquid, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3139, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing liquid, n.o.s. 5.1 UN3139 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing liquid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3099, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing liquid, toxic, n.o.s. 5.1 UN3099 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing liquid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing solid, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3085, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing solid, corrosive, n.o.s. 5.1 UN3085 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing solid, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing solid, flammable, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3137, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing solid, flammable, n.o.s. 5.1 UN3137 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing solid, flammable, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing solid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN1479, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing solid, n.o.s. 5.1 UN1479 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing solid, self-heating, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3100, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing solid, self-heating, n.o.s. 5.1 UN3100 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing solid, self-heating, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing solid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3087, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing solid, toxic, n.o.s. 5.1 UN3087 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing solid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing solid, water reactive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3121, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxidizing solid, water reactive, n.o.s. 5.1 UN3121 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxidizing solid, water reactive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Oxidizing substances and organic peroxides (Hazard Class 5) — international mail

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** international mail

**Conditions:** All oxidizing substances and organic peroxides are prohibited from international mail

> International Mail: All oxidizing substances and organic peroxides are prohibited.

Source: <https://pe.usps.com/text/pub52/pub52c3_024.htm>

Oxidizing substances and organic peroxides (Hazard Class 5) — international mail — Postal shipping restrictions by item category


**Item category:** Oxidizing substances or organic peroxides qualifying as Limited Quantity

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via air or surface transportation

**Conditions:** Permitted if qualify as Limited Quantity air or Limited Quantity surface materials

> Domestic Mail via Air or Surface Transportation: Oxidizing substances or organic peroxides that qualify as Limited Quantity air or Limited Quantity surface are permitted.

Source: <https://pe.usps.com/text/pub52/pub52c3_024.htm>

Oxidizing substances or organic peroxides qualifying as Limited Quantity — Postal shipping restrictions by item category


**Item category:** Oxygen, Compressed (UN1072) — Division 2.2 nonflammable gas

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail

**Conditions:** Mailable if qualifies as Limited Quantity material; must follow applicable packaging instructions

> Oxygen, Compressed (UN1072): Division 2.2 nonflammable gas. Compressed oxygen is mailable if it qualifies as a Limited Quantity material

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Oxygen, Compressed (UN1072) — Division 2.2 nonflammable gas — Postal shipping restrictions by item category


**Item category:** Oxygen, compressed

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.2, UN1072, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Oxygen, compressed 2.2 UN1072 n/a 2B 2B

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxygen, compressed — Postal shipping restrictions by item category


**Item category:** Oxygen difluoride, compressed

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN2190, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxygen difluoride, compressed 2.3 UN2190 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxygen difluoride, compressed — Postal shipping restrictions by item category


**Item category:** Oxygen generator, chemical (including when contained in associated equipment, e.g., passenger service units (PSUs), portable breathing equipment (PBE), etc.)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3356, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxygen generator, chemical (including when contained in associated equipment, e.g., passenger service units (PSUs), portable breathing equipment (PBE), etc.) 5.1 UN3356 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxygen generator, chemical (including when contained in associated equipment, e.g., passenger service units (PSUs), portable breathing equipment (PBE), etc.) — Postal shipping restrictions by item category


**Item category:** Oxygen generator, chemical, spent

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, NA3356, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxygen generator, chemical, spent 9 NA3356 III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxygen generator, chemical, spent — Postal shipping restrictions by item category


**Item category:** Oxygen, refrigerated liquid (cryogenic liquid)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.2, UN1073, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Oxygen, refrigerated liquid (cryogenic liquid) 2.2 UN1073 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Oxygen, refrigerated liquid (cryogenic liquid) — Postal shipping restrictions by item category


**Item category:** Oxygen, Refrigerated Liquid (UN1073)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Prohibited from mailing under any circumstances

> Oxygen, Refrigerated Liquid (UN1073): (Also known as liquid oxygen) is prohibited from mailing under any circumstances.

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Oxygen, Refrigerated Liquid (UN1073) — Postal shipping restrictions by item category


**Item category:** p-Diazidobenzene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> p-Diazidobenzene Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

p-Diazidobenzene — Postal shipping restrictions by item category


**Item category:** p-Nitrosodimethylaniline

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN1369, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> p-Nitrosodimethylaniline 4.2 UN1369 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

p-Nitrosodimethylaniline — Postal shipping restrictions by item category


**Item category:** p-Xylyl diazide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> p-Xylyl diazide Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

p-Xylyl diazide — Postal shipping restrictions by item category


**Item category:** Packages with old hazmat markings or stickers (reused boxes)

**Carrier:** USPS

**Restriction type:** hazmat noncompliance fee risk

**Scope:** online marketplace seller shipments (Poshmark)

**Conditions:** Reused boxes with old hazmat labels will be flagged even if item inside is not hazardous; seller must remove or fully cover any existing hazmat markings before shipping

> reused boxes with old markings — even if your item is harmless, a box with an old hazmat sticker will be flagged

Source: <https://blog.poshmark.com/2026/07/09/59935/>

Packages with old hazmat markings or stickers (reused boxes) — Postal shipping restrictions by item category


**Item category:** Paint and related items (UN1263) — lacquer, varnish, shellac, etc.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via surface transportation

**Conditions:** Mailable if qualify as Limited Quantity surface material and meet quantity limitations and packaging requirements; Packaging Instruction 3A or 3B as applicable

> Paint and Related Items (UN1263): A flammable or combustible liquid, which includes items such as lacquer, paint-thinning or paint-drying compounds, shellac, varnish, liquid aluminum, liquid bronze, liquid gold, liquid wood filler, and liquid lacquer base. They are mailable if they qualify as Limited Quantity surface material

Source: <https://pe.usps.com/text/pub52/pub52c3_022.htm>

Paint and related items (UN1263) — lacquer, varnish, shellac, etc. — Postal shipping restrictions by item category


**Item category:** Paint, corrosive, flammable (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 8, UN3470, packing group II; domestic mail air: Prohibited; domestic mail surface: 8A

> Paint, corrosive, flammable (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base) 8 UN3470 II Prohibited 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint, corrosive, flammable (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base) — Postal shipping restrictions by item category


**Item category:** Paint, flammable, corrosive (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3469, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Paint, flammable, corrosive (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base) 3 UN3469 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint, flammable, corrosive (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base) — Postal shipping restrictions by item category


**Item category:** Paint including paint, lacquer, enamel, stain, shellac solutions, varnish, polish, liquid filler, and liquid lacquer base

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1263, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Paint including paint, lacquer, enamel, stain, shellac solutions, varnish, polish, liquid filler, and liquid lacquer base 3 UN1263 I, II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint including paint, lacquer, enamel, stain, shellac solutions, varnish, polish, liquid filler, and liquid lacquer base — Postal shipping restrictions by item category


**Item category:** Paint or Paint related material

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN3066, packing group II, III; domestic mail air: 8A; domestic mail surface: 8A

> Paint or Paint related material 8 UN3066 II, III 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint or Paint related material — Postal shipping restrictions by item category


**Item category:** Paint related material corrosive, flammable (including paint thinning or reducing compound)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 8, UN3470, packing group II; domestic mail air: Prohibited; domestic mail surface: 8A

> Paint related material corrosive, flammable (including paint thinning or reducing compound) 8 UN3470 II Prohibited 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint related material corrosive, flammable (including paint thinning or reducing compound) — Postal shipping restrictions by item category


**Item category:** Paint related material, flammable, corrosive (including paint thinning or reducing compound)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3469, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Paint related material, flammable, corrosive (including paint thinning or reducing compound) 3 UN3469 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint related material, flammable, corrosive (including paint thinning or reducing compound) — Postal shipping restrictions by item category


**Item category:** Paint related material including paint thinning, drying, removing, or reducing compound

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1263, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: 8A

> Paint related material including paint thinning, drying, removing, or reducing compound 3 UN1263 I, II, III Prohibited 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paint related material including paint thinning, drying, removing, or reducing compound — Postal shipping restrictions by item category


**Item category:** Paint thinner

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic US

**Conditions:** Classified as flammable liquid. Requires hazmat declaration. $50 noncompliance fee if undeclared, effective July 12, 2026.

> Paint thinner | Flammable liquid | UN1263

Source: <https://selleressentials.com/usps-hazmat-noncompliance-fee-2026/>

Paint thinner — Postal shipping restrictions by item category

carrier, conditions, restriction_type, scope


**Item category:** Paint

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic

**Conditions:** Flammable or combustible paint accepted if it qualifies as a consumer commodity; water-based paint is not regulated as hazardous

> Flammable or combustible paint and paint-related items are generally accepted for mailing, provided the material can qualify as a consumer commodity material or ORM-D (for surface only), and is sent within the quantity limitations and packaging requirements. Latex Paint or a similar water-based paint product that is not flammable or combustible is not regulated as a hazardous material, and therefore, is not restricted.

Source: <https://www.usps.com/ship/shipping-restrictions.htm>

Paint — Postal shipping restrictions by item category


**Item category:** Paper, unsaturated oil treated incompletely dried (including carbon paper)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN1379, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Paper, unsaturated oil treated incompletely dried (including carbon paper) 4.2 UN1379 III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paper, unsaturated oil treated incompletely dried (including carbon paper) — Postal shipping restrictions by item category


**Item category:** Paraformaldehyde

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 4.1, UN2213, packing group III; domestic mail air: Prohibited; domestic mail surface: 4A

> Paraformaldehyde 4.1 UN2213 III Prohibited 4A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paraformaldehyde — Postal shipping restrictions by item category


**Item category:** Paraldehyde

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1264, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Paraldehyde 3 UN1264 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Paraldehyde — Postal shipping restrictions by item category


**Item category:** Pentachloroethane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1669, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pentachloroethane 6.1 UN1669 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentachloroethane — Postal shipping restrictions by item category


**Item category:** Pentachlorophenol

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3155, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pentachlorophenol 6.1 UN3155 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentachlorophenol — Postal shipping restrictions by item category


**Item category:** Pentaerythrite tetranitrate (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Prohibited Pentaerythrite tetranitrate (dry)

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentaerythrite tetranitrate (dry) — Postal shipping restrictions by item category


**Item category:** Pentaerythrite tetranitrate mixture, desensitized, solid, n.o.s. or Pentaerythritol tetranitrate mixture, desensitized, solid, n.o.s. or PETN mixture, desensitized, solid, n.o.s., with more than 10 percent but not more than 20 percent PETN, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN3344, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pentaerythrite tetranitrate mixture, desensitized, solid, n.o.s. or Pentaerythritol tetranitrate mixture, desensitized, solid, n.o.s. or PETN mixture, desensitized, solid, n.o.s., with more than 10 percent but not more than 20 percent PETN, by mass 4.1 UN3344 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentaerythrite tetranitrate mixture, desensitized, solid, n.o.s. or Pentaerythritol tetranitrate mixture, desensitized, solid, n.o.s. or PETN mixture, desensitized, solid, n.o.s., with more than 10 percent but not more than 20 percent PETN, by mass — Postal shipping restrictions by item category


**Item category:** Pentaerythrite tetranitrate or Pentaerythritol tetranitrate or PETN, with not less than 7 percent wax by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0411, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pentaerythrite tetranitrate or Pentaerythritol tetranitrate or PETN, with not less than 7 percent wax by mass 1.1D UN0411 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentaerythrite tetranitrate or Pentaerythritol tetranitrate or PETN, with not less than 7 percent wax by mass — Postal shipping restrictions by item category


**Item category:** Pentamethylheptane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2286, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Pentamethylheptane 3 UN2286 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentamethylheptane — Postal shipping restrictions by item category


**Item category:** Pentane-2,4-dione

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2310, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Pentane-2,4-dione 3 UN2310 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentane-2,4-dione — Postal shipping restrictions by item category


**Item category:** Pentanes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1265, packing group I, II; domestic mail air: Prohibited; domestic mail surface: 3A

> Pentanes 3 UN1265 I, II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentanes — Postal shipping restrictions by item category


**Item category:** Pentanitroaniline (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Pentanitroaniline (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentanitroaniline (dry) — Postal shipping restrictions by item category


**Item category:** Pentanols

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1105, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Pentanols 3 UN1105 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentanols — Postal shipping restrictions by item category


**Item category:** Pentaporane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.2, UN1380, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pentaporane 4.2 UN1380 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentaporane — Postal shipping restrictions by item category


**Item category:** Pentolite, dry or wetted with less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0151, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pentolite, dry or wetted with less than 15 percent water, by mass 1.1D UN0151 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pentolite, dry or wetted with less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** per 348.22b Batteries, wet, filled with acid, electric storage

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2794, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> per 348.22b Batteries, wet, filled with acid, electric storage 8 UN2794 III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

per 348.22b Batteries, wet, filled with acid, electric storage — Postal shipping restrictions by item category


**Item category:** Perchlorates, inorganic, aqueous solution, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3211, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Perchlorates, inorganic, aqueous solution, n.o.s. 5.1 UN3211 II, III 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchlorates, inorganic, aqueous solution, n.o.s. — Postal shipping restrictions by item category


**Item category:** Perchlorates, inorganic, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN1481, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Perchlorates, inorganic, n.o.s. 5.1 UN1481 II, III 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchlorates, inorganic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Perchloric acid with more than 50 percent but not more than 72 percent acid, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN1873, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Perchloric acid with more than 50 percent but not more than 72 percent acid, by mass 5.1 UN1873 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchloric acid with more than 50 percent but not more than 72 percent acid, by mass — Postal shipping restrictions by item category


**Item category:** Perchloric acid, with more than 72 percent acid by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Perchloric acid, with more than 72 percent acid by mass Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchloric acid, with more than 72 percent acid by mass — Postal shipping restrictions by item category


**Item category:** Perchloric acid with not more than 50 percent acid by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1802, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Perchloric acid with not more than 50 percent acid by mass 8 UN1802 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchloric acid with not more than 50 percent acid by mass — Postal shipping restrictions by item category


**Item category:** Perchloric acid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Nonmailable Division 5.1 oxidizing substance

> Perchloric acid.

Source: <https://pe.usps.com/text/pub52/pub52c3_024.htm>

Perchloric acid — Postal shipping restrictions by item category


**Item category:** Perchloromethyl mercaptan

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1670, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Perchloromethyl mercaptan 6.1 UN1670 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchloromethyl mercaptan — Postal shipping restrictions by item category


**Item category:** Perchloryl fluoride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN3083, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Perchloryl fluoride 2.3 UN3083 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perchloryl fluoride — Postal shipping restrictions by item category


**Item category:** Perfluoro (ethyl vinyl ether)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN3154, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Perfluoro (ethyl vinyl ether) 2.1 UN3154 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perfluoro (ethyl vinyl ether) — Postal shipping restrictions by item category


**Item category:** Perfluoro (methyl vinyl ether)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN3153, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Perfluoro (methyl vinyl ether) 2.1 UN3153 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perfluoro (methyl vinyl ether) — Postal shipping restrictions by item category


**Item category:** Perfume / cologne

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic US

**Conditions:** Classified as flammable liquid due to alcohol content. Requires hazmat declaration and compliant packaging. $50 noncompliance fee if undeclared, effective July 12, 2026.

> Perfume / cologne | Flammable liquid (alcohol) | UN1266

Source: <https://selleressentials.com/usps-hazmat-noncompliance-fee-2026/>

Perfume / cologne — Postal shipping restrictions by item category


**Item category:** Perfume containing alcohol

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic

**Conditions:** may not be shipped internationally or mailed domestically using air transportation

> Perfume containing alcohol may not be shipped internationally or mailed domestically using air transportation.

Source: <https://www.usps.com/ship/shipping-restrictions.htm>

Perfume containing alcohol — Postal shipping restrictions by item category


**Item category:** Perfume

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** online marketplace seller shipments (Poshmark)

**Conditions:** Subject to USPS hazmat requirements and Poshmark Terms of Service; $50 USPS noncompliance fee applies if improperly declared/labeled; Poshmark absorbs $45 of fee after August 1 2026, seller pays $5

> regulated contents (perfume, nail polish, aerosol sprays, electronics with lithium-ion batteries)

Source: <https://blog.poshmark.com/2026/07/09/59935/>

Perfume — Postal shipping restrictions by item category


**Item category:** Perfumery products with flammable solvents

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1266, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Perfumery products with flammable solvents 3 UN1266 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Perfumery products with flammable solvents — Postal shipping restrictions by item category


**Item category:** Perfumes

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** seller shipments (Etsy)

**Conditions:** May have special shipping requirements under USPS hazardous materials rules; $50 noncompliance fee for undeclared or improperly prepared hazardous materials effective July 12 2026

> Some items, such as certain candles, perfumes, aerosols, nail polish, or items containing lithium batteries, may have special shipping requirements.

Source: <https://www.valueaddedresource.net/poshmark-cover-usps-hazardous-non-compliance-fee/>

Perfumes — Postal shipping restrictions by item category


**Item category:** Perfumes and colognes

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** commercial package shipments

**Conditions:** Listed by the Department of Transportation as posing a significant safety risk while being transported; $7.50 hazmat handling fee for Priority Mail; $50 noncompliance fee for packages not properly declared and labeled across all commercial packages including Ground Advantage (effective July 12 2026)

> Essential oils, nail polish (and nail polish remover), perfumes and colognes, hand sanitizer, inks, stains and varnishes, hairspray, and electronics with a lithium battery are among the products listed by the Department of Transportation as posing a significant safety risk while being transported.

Source: <https://www.ecommercebytes.com/2026/07/05/new-usps-noncompliance-fee-could-take-sellers-by-surprise/>

Perfumes and colognes — Postal shipping restrictions by item category


**Item category:** Perfumes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic, ground only

**Conditions:** Perfume containing alcohol may not be shipped internationally or by air; may be shipped domestically by ground transportation

> Perfume containing alcohol may not be shipped internationally or mailed domestically using air transportation. Perfume containing alcohol, however, may be shipped within the United States by ground transportation.

Source: <https://www.usps.com/ship/shipping-restrictions.htm>


**Item category:** Perishable Items

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic

**Conditions:** must be specially packaged and mailed so that they arrive before they begin to deteriorate

> Perishable items are materials that can deteriorate in the mail, such as live animals, food, and plants. Permissible perishable items are sent at the mailer’s own risk. These items must be specially packaged and mailed so that they arrive before they begin to deteriorate.

Source: <https://www.usps.com/ship/shipping-restrictions.htm>

Perishable Items — Postal shipping restrictions by item category


**Item category:** Permanganates, inorganic, aqueous solution, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3214, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Permanganates, inorganic, aqueous solution, n.o.s. 5.1 UN3214 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Permanganates, inorganic, aqueous solution, n.o.s. — Postal shipping restrictions by item category


**Item category:** Permanganates, inorganic, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN1482, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Permanganates, inorganic, n.o.s. 5.1 UN1482 II, III 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Permanganates, inorganic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Peroxides, inorganic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN1483, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Peroxides, inorganic, n.o.s. 5.1 UN1483 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Peroxides, inorganic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Peroxyacetic acid, with more than 43 percent and with more than 6 percent hydrogen peroxide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Peroxyacetic acid, with more than 43 percent and with more than 6 percent hydrogen peroxide Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Peroxyacetic acid, with more than 43 percent and with more than 6 percent hydrogen peroxide — Postal shipping restrictions by item category


**Item category:** Persulfates, inorganic, aqueous solution, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3216, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Persulfates, inorganic, aqueous solution, n.o.s. 5.1 UN3216 III 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Persulfates, inorganic, aqueous solution, n.o.s. — Postal shipping restrictions by item category


**Item category:** Persulfates, inorganic, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN3215, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Persulfates, inorganic, n.o.s. 5.1 UN3215 III 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Persulfates, inorganic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Pesticides, insecticides, herbicides with oral LD50 greater than 300 mg/kg (nonregulated)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** all domestic mail

**Conditions:** Mailable but must be packaged in rigid outer packaging per 339.4 and able to withstand normal transit; liquids must also follow 451.3(a)

> Liquids and solids such as pesticides, insecticides, herbicides, and irritating material ( 346.11 (b) ), that do not meet the classification criteria of a hazardous material per 49 CFR § 172.101 with an oral LD50 value greater than 300 mg/kg are mailable but must be packaged in rigid outer packaging

Source: <https://pe.usps.com/text/pub52/pub52c3_025.htm>

Pesticides, insecticides, herbicides with oral LD50 greater than 300 mg/kg (nonregulated) — Postal shipping restrictions by item category

carrier, conditions, item_category, scope


**Item category:** Pesticides, liquid, flammable, toxic, flashpoint less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3021, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pesticides, liquid, flammable, toxic, flashpoint less than 23° C 3 UN3021 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pesticides, liquid, flammable, toxic, flashpoint less than 23° C — Postal shipping restrictions by item category


**Item category:** Pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2903, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pesticides, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN2903 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pesticides, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Pesticides, liquid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2902, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pesticides, liquid, toxic, n.o.s. 6.1 UN2902 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pesticides, liquid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Pesticides, solid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2588, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Pesticides, solid, toxic, n.o.s. 6.1 UN2588 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Pesticides, solid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Petroleum crude oil

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1267, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Petroleum crude oil 3 UN1267 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Petroleum crude oil — Postal shipping restrictions by item category


**Item category:** Petroleum distillates, n.o.s. or Petroleum products, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1268, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Petroleum distillates, n.o.s. or Petroleum products, n.o.s. 3 UN1268 I, II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Petroleum distillates, n.o.s. or Petroleum products, n.o.s. — Postal shipping restrictions by item category


**Item category:** Petroleum gases, liquified or Liquified petroleum gas

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN1075, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Petroleum gases, liquified or Liquified petroleum gas 2.1 UN1075 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Petroleum gases, liquified or Liquified petroleum gas — Postal shipping restrictions by item category


**Item category:** Petroleum oil

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, NA1270, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Petroleum oil 3 NA1270 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Petroleum oil — Postal shipping restrictions by item category


**Item category:** Petroleum sour crude oil, flammable, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3494, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Petroleum sour crude oil, flammable, toxic 3 UN3494 I, II, III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Petroleum sour crude oil, flammable, toxic — Postal shipping restrictions by item category


**Item category:** Phenacyl bromide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2645, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenacyl bromide 6.1 UN2645 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenacyl bromide — Postal shipping restrictions by item category


**Item category:** Phenetidines

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2311, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Phenetidines 6.1 UN2311 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenetidines — Postal shipping restrictions by item category


**Item category:** Phenol, molten

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2312, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenol, molten 6.1 UN2312 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenol, molten — Postal shipping restrictions by item category


**Item category:** Phenol, solid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1671, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenol, solid 6.1 UN1671 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenol, solid — Postal shipping restrictions by item category


**Item category:** Phenol solutions

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2821, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenol solutions 6.1 UN2821 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenol solutions — Postal shipping restrictions by item category


**Item category:** Phenolsulfonic acid, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1803, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Phenolsulfonic acid, liquid 8 UN1803 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenolsulfonic acid, liquid — Postal shipping restrictions by item category


**Item category:** Phenoxyacetic acid derivative pesticide, liquid, flammable, toxic flashpoint less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3346, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenoxyacetic acid derivative pesticide, liquid, flammable, toxic flashpoint less than 23° C 3 UN3346 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenoxyacetic acid derivative pesticide, liquid, flammable, toxic flashpoint less than 23° C — Postal shipping restrictions by item category


**Item category:** Phenoxyacetic acid derivative pesticide, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3347, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenoxyacetic acid derivative pesticide, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN3347 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenoxyacetic acid derivative pesticide, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Phenoxyacetic acid derivative pesticide, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3348, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenoxyacetic acid derivative pesticide, liquid, toxic 6.1 UN3348 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenoxyacetic acid derivative pesticide, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Phenoxyacetic acid derivative pesticide, solid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3345, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenoxyacetic acid derivative pesticide, solid, toxic 6.1 UN3345 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenoxyacetic acid derivative pesticide, solid, toxic — Postal shipping restrictions by item category


**Item category:** Phenyl chloroformate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2746, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenyl chloroformate 6.1 UN2746 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyl chloroformate — Postal shipping restrictions by item category


**Item category:** Phenyl isocyanate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2487, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenyl isocyanate 6.1 UN2487 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyl isocyanate — Postal shipping restrictions by item category


**Item category:** Phenyl mercaptan

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2337, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenyl mercaptan 6.1 UN2337 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyl mercaptan — Postal shipping restrictions by item category


**Item category:** Phenyl phosphorus dichloride

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2798, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Phenyl phosphorus dichloride 8 UN2798 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyl phosphorus dichloride — Postal shipping restrictions by item category


**Item category:** Phenyl phosphorus thiodichloride

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2799, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Phenyl phosphorus thiodichloride 8 UN2799 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyl phosphorus thiodichloride — Postal shipping restrictions by item category


**Item category:** Phenyl urea pesticides, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3002, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenyl urea pesticides, liquid, toxic 6.1 UN3002 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyl urea pesticides, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Phenylacetonitrile, liquid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2470, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Phenylacetonitrile, liquid 6.1 UN2470 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylacetonitrile, liquid — Postal shipping restrictions by item category


**Item category:** Phenylacetyl chloride

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2577, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Phenylacetyl chloride 8 UN2577 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylacetyl chloride — Postal shipping restrictions by item category


**Item category:** Phenylcarbylamine chloride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1672, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenylcarbylamine chloride 6.1 UN1672 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylcarbylamine chloride — Postal shipping restrictions by item category


**Item category:** Phenylenediamines (o-; m-; p-;)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1673, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Phenylenediamines (o-; m-; p-;) 6.1 UN1673 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylenediamines (o-; m-; p-;) — Postal shipping restrictions by item category


**Item category:** Phenylhydrazine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2572, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenylhydrazine 6.1 UN2572 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylhydrazine — Postal shipping restrictions by item category


**Item category:** Phenylmercuric acetate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1674, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenylmercuric acetate 6.1 UN1674 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylmercuric acetate — Postal shipping restrictions by item category


**Item category:** Phenylmercuric compounds, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2026, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenylmercuric compounds, n.o.s. 6.1 UN2026 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylmercuric compounds, n.o.s. — Postal shipping restrictions by item category


**Item category:** Phenylmercuric hydroxide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1894, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenylmercuric hydroxide 6.1 UN1894 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylmercuric hydroxide — Postal shipping restrictions by item category


**Item category:** Phenylmercuric nitrate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1895, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenylmercuric nitrate 6.1 UN1895 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenylmercuric nitrate — Postal shipping restrictions by item category


**Item category:** Phenyltrichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1804, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phenyltrichlorosilane 8 UN1804 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phenyltrichlorosilane — Postal shipping restrictions by item category


**Item category:** Phosgene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN1076, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosgene 2.3 UN1076 Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosgene — Postal shipping restrictions by item category


**Item category:** Phosphine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN2199, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphine 2.3 UN2199 Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphine — Postal shipping restrictions by item category


**Item category:** Phosphoric acid, solid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN3453, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Phosphoric acid, solid 8 UN3453 III 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphoric acid, solid — Postal shipping restrictions by item category


**Item category:** Phosphoric acid solution

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1805, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Phosphoric acid solution 8 UN1805 III 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphoric acid solution — Postal shipping restrictions by item category


**Item category:** Phosphorous acid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2834, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Phosphorous acid 8 UN2834 III 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorous acid — Postal shipping restrictions by item category


**Item category:** Phosphorus, amorphous

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1338, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus, amorphous 4.1 UN1338 III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus, amorphous — Postal shipping restrictions by item category


**Item category:** Phosphorus heptasulfide, free from yellow or white phosphorus

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1339, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus heptasulfide, free from yellow or white phosphorus 4.1 UN1339 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus heptasulfide, free from yellow or white phosphorus — Postal shipping restrictions by item category


**Item category:** Phosphorus oxybromide, molten

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2576, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus oxybromide, molten 8 UN2576 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus oxybromide, molten — Postal shipping restrictions by item category


**Item category:** Phosphorus oxybromide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1939, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus oxybromide 8 UN1939 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus oxybromide — Postal shipping restrictions by item category


**Item category:** Phosphorus oxychloride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1810, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus oxychloride 8 UN1810 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus oxychloride — Postal shipping restrictions by item category


**Item category:** Phosphorus pentabromide

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2691, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Phosphorus pentabromide 8 UN2691 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus pentabromide — Postal shipping restrictions by item category


**Item category:** Phosphorus pentachloride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1806, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus pentachloride 8 UN1806 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus pentachloride — Postal shipping restrictions by item category


**Item category:** Phosphorus pentafluoride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN2198, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus pentafluoride 2.3 UN2198 Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus pentafluoride — Postal shipping restrictions by item category


**Item category:** Phosphorus pentasulfide, free from yellow or white phosphorus

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 4.3, UN1340, packing group II; domestic mail air: Prohibited; domestic mail surface: 4A

> Phosphorus pentasulfide, free from yellow or white phosphorus 4.3 UN1340 II Prohibited 4A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus pentasulfide, free from yellow or white phosphorus — Postal shipping restrictions by item category


**Item category:** Phosphorus pentoxide

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1807, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Phosphorus pentoxide 8 UN1807 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus pentoxide — Postal shipping restrictions by item category


**Item category:** Phosphorus sesquisulfide, free from yellow or white phosphorus

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1341, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Phosphorus sesquisulfide, free from yellow or white phosphorus 4.1 UN1341 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Phosphorus sesquisulfide, free from yellow or white phosphorus — Postal shipping restrictions by item category