Naphthalene
For Naphthalene, cas no. is 91-20-3; pel (ppm) is 10; pel (mg/m³) is 50, verified against its source on 2026-08-05.
- Substance
- Naphthalene
- CAS No.
- 91-20-3
- PEL (ppm)
- 10
- PEL (mg/m³)
- 50
What the source says
Naphthalene | 91-20-3 | 10 | 50 | - |
— osha.gov, retrieved 2026-08-05
Sources disagree
More than one authority states this, and they do not state the same thing. Both are reproduced with the source each came from — deciding between them is yours, not ours.
PEL (ppm)
osha.gov says pel (ppm) is 10, as of 2026-08-05.
Naphthalene | 91-20-3 | 10 | 50 | - |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (ppm) is 0.1, as of 2026-08-05.
91203 | S | Naphthalene | 0.1 | 0.5
https://www.dir.ca.gov/title8/5155.html
PEL (mg/m³)
osha.gov says pel (mg/m³) is 50, as of 2026-08-05.
Naphthalene | 91-20-3 | 10 | 50 | - |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (mg/m³) is 0.5, as of 2026-08-05.
91203 | S | Naphthalene | 0.1 | 0.5
Sources
- osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
- dir.ca.govhttps://www.dir.ca.gov/title8/5155.html