The airborne exposure level that triggers mandatory medical surveillance under each OSHA substance-specific standard (29 CFR 1910 Subpart Z), compared across all regulated substances. Each record is one substance, carrying its action level, PEL, the exposure duration that triggers surveillance, the medical exam scope and frequency, biological monitoring requirements if any, and the record retention period. Answers 'what is the action level for lead', 'at what exposure must I provide medical exams for benzene workers', 'how often does cadmium biological monitoring need to happen', and 'which OSHA substances require 40-year record retention'. The action level is typically half the PEL but not always, and the surveillance trigger conditions vary wildly: lead uses blood lead levels, cadmium uses urine cadmium, and most others use airborne concentration plus days-per-year thresholds.

US federal regulation — 17 USC 105, no copyright

OSHA medical surveillance trigger thresholds by substance


**Substance:** 1,2-dibromo-3-chloropropane

**CFR section:** 1910.1044

**Action level:** none defined

**PEL:** 1 part DBCP per billion parts of air (ppb) as an 8-hour time-weighted average

**Surveillance trigger:** employees who work in regulated areas and employees who are subjected to DBCP exposures in an emergency situation

**Exam frequency:** At the time of initial assignment, and annually thereafter

**Record retention:** at least 40 years or the duration of employment plus 20 years, whichever is longer

> DANGER 1,2-Dibromo-3-chloropropane CANCER HAZARD (p) Recordkeeping —(1) Exposure monitoring. (i) The employer shall establish and maintain an accurate <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=16d5cbe4e2780e9007037fa6a12974c6&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1044> record of all monitoring required by paragraph (f) of this section . (ii) This record shall include: (a) The dates, number, duration and results of each of the samples taken, including a description of the sampling procedure used to determine representative employee exposure ; (b) A description of the sampling and analytical methods used; (c) Type of respiratory protective devices worn, if any; and (d) Name and job classification of the employee monitored and of all other employees whose exposure the measurement is intended to represent. (iii) The employer shall maintain this record for at least 40 years or the duration of employment plus 20 years, whichever is longer.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1044>

1,2-dibromo-3-chloropropane — OSHA medical surveillance trigger thresholds by substance

action_level, exam_frequency, pel, surveillance_trigger


**Substance:** 1,3-Butadiene

**CFR section:** 1910.1051

**Action level:** 0.5 ppm calculated as an eight (8)-hour time-weighted average

**PEL:** one (1) part BD per million parts of air (ppm) measured as an eight (8)-hour time-weighted average; five parts of BD per million parts of air (5 ppm) as determined over a sampling period of fifteen (15) minutes

**Surveillance trigger:** each employee with exposure to BD at concentrations at or above the action level on 30 or more days or for employees who have or may have exposure to BD at or above the PELs on 10 or more days a year

**Exam frequency:** At time of initial assignment; at least every 5 years; within 30 days after exposure during emergency; at reassignment to non-BD area if 12 months or more have elapsed since last exam; at termination if 12 months or more have elapsed since last exam

**Record retention:** duration of employment plus 30 years

> 1910.1051 1,3-Butadiene." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1051>

1,3-Butadiene — OSHA medical surveillance trigger thresholds by substance

action_level, exam_frequency, pel, record_retention, surveillance_trigger


**Substance:** 13 Carcinogens (4-Nitrobiphenyl, etc.)

**CFR section:** 1910.1003

**Action level:** none defined

**PEL:** none defined (standard prohibits entry to regulated areas without authorization; no numerical PEL stated)

**Surveillance trigger:** employees considered for assignment to enter regulated areas, and for authorized employees

**Exam frequency:** at least annually (periodic physical examinations, not less often than annually, following the preassignment examination)

**Record retention:** duration of the employee's employment

> 1910.1003 13 Carcinogens (4-Nitrobiphenyl, etc.)." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1003>

13 Carcinogens (4-Nitrobiphenyl, etc.) — OSHA medical surveillance trigger thresholds by substance


**Substance:** Acrylonitrile

**CFR section:** 1910.1045

**Action level:** 1 ppm as an eight (8)-hour time-weighted average

**PEL:** two (2) parts acrylonitrile per million parts of air (2 ppm) as an eight (8)-hour time-weighted average; ten (10) ppm as averaged over any fifteen (15)-minute period

**Surveillance trigger:** each employee who is or will be exposed to AN at or above the action level, without regard to the use of respirators

**Exam frequency:** At the time of initial assignment, or upon institution of the medical surveillance program; at least annually thereafter

**Record retention:** at least forty (40) years, or for the duration of employment plus twenty (20) years, whichever is longer

> <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=73fb91be2169421e83a117ba377f14a6&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1045> the employer 's reliance on the data, as provided in paragraph (q) of this section . (b) Definitions. Acrylonitrile or AN means acrylonitrile monomer, chemical formula CH 2 = CHCN. <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=dd84298aa9139708242b9ada1c8295b9&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1045> Action level means a concentration of AN of 1 ppm as an eight (8)-hour time-weighted average.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1045>

Acrylonitrile — OSHA medical surveillance trigger thresholds by substance

exam_frequency, pel, record_retention, surveillance_trigger


**Substance:** Asbestos

**CFR section:** 1910.1001

**Action level:** none defined

**PEL:** 0.1 fiber per cubic centimeter of air as an eight (8)-hour time-weighted average (TWA); excursion limit: 1 f/cc averaged over a sampling period of thirty (30) minutes

**Surveillance trigger:** exposed to airborne concentrations of fibers of asbestos at or above the TWA and/or excursion limit

**Exam frequency:** annually (periodic medical examinations shall be made available annually)

**Record retention:** duration of employment plus thirty (30) years

> <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=b3c19faa4963f563c95da8d16744338e&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1001> HEPA filter . (l) Medical surveillance —(1) General —(i) Employees covered . The employer shall institute a medical surveillance program for all employees who are or will be exposed to airborne concentrations of fibers of asbestos at or above the TWA and/or excursion limit.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1001>

Asbestos — OSHA medical surveillance trigger thresholds by substance

action_level, exam_frequency, pel, record_retention


**Substance:** Benzene

**CFR section:** 1910.1028

**Action level:** 0.5 ppm (TWA)

**PEL:** 1 ppm (TWA); 5 ppm (STEL, 15 minutes)

**Surveillance trigger:** Employees exposed at or above the action level 30 or more days per year; or at or above the PELs 10 or more days per year

**Exam frequency:** Annually

**Record retention:** Duration of employment plus 30 years

> DANGER CONTAINS BENZENE CANCER HAZARD (3) Information and training . (i) The employer shall provide employees with information and training at the time of their initial assignment to a work area where benzene is present. If exposures are above the action level , employees shall be provided with information and training at least annually thereafter. (ii) The <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=5c8ae3ca6b82c8003a8269dbf145e2b2&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1028>

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1028>

Benzene — OSHA medical surveillance trigger thresholds by substance

action_level, pel, record_retention, surveillance_trigger


**Substance:** Beryllium

**CFR section:** 1910.1024

**Action level:** 0.1 micrograms per cubic meter of air (µg/m3) calculated as an 8-hour time-weighted average (TWA)

**PEL:** 0.2 µg/m3 calculated as an 8-hour TWA; 2.0 µg/m3 as determined over a sampling period of 15 minutes

**Surveillance trigger:** Who is or is reasonably expected to be exposed at or above the action level for more than 30 days per year; who shows signs or symptoms of CBD or other beryllium-related health effects; who is exposed to beryllium during an emergency; or whose most recent written medical opinion recommends periodic medical surveillance

**Exam frequency:** Initial examination; at least every two years thereafter for each employee who continues to meet the criteria; at termination of employment unless an examination has been provided in the six months prior to termination

**Record retention:** maintained and made available in accordance with the Records Access standard (§ 1910.1020)

> 1910.1024 Beryllium." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1024>

Beryllium — OSHA medical surveillance trigger thresholds by substance


**Substance:** Bloodborne pathogens

**CFR section:** 1910.1030

**Action level:** none defined

**PEL:** none defined

**Surveillance trigger:** All employees with occupational exposure (reasonably anticipated skin, eye, mucous membrane, or parenteral contact with blood or other potentially infectious materials)

**Exam frequency:** Hepatitis B vaccination offered within 10 working days of initial assignment; post-exposure evaluation made immediately available after each exposure incident

**Record retention:** Duration of employment plus 30 years

> 1910.1030 Bloodborne pathogens." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1030>

Bloodborne pathogens — OSHA medical surveillance trigger thresholds by substance


**Substance:** Cadmium

**CFR section:** 1910.1027

**Action level:** 2.5 µg/m3 (TWA)

**PEL:** 5 µg/m3 (TWA)

**Surveillance trigger:** Employees exposed at or above the action level on 30 or more days per year (twelve consecutive months)

**Exam frequency:** Periodic medical examination at least biennially; biological sampling at least annually

**Record retention:** Duration of employment plus 30 years

> 1910.1027 Cadmium." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1027>

Cadmium — OSHA medical surveillance trigger thresholds by substance


**Substance:** Coke oven emissions

**CFR section:** 1910.1029

**Action level:** none defined

**PEL:** 150 micrograms per cubic meter of air (150 µg/m3), averaged over any 8-hour period

**Surveillance trigger:** all employees who are employed in a regulated area at least 30 days per year

**Exam frequency:** at least annually

**Record retention:** at least 40 years, or for the duration of employment plus 20 years, whichever is longer

> (iii) The training program shall be provided at least annually for all employees who are employed in the regulated area , except that training regarding the occupational safety and <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=9b27d2ff04887773c45ec67cb3d05f70&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1029> health hazards associated with exposure to coke oven emissions

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1029>

Coke oven emissions — OSHA medical surveillance trigger thresholds by substance


**Substance:** Cotton dust

**CFR section:** 1910.1043

**Action level:** 100 µg/m3 (yarn manufacturing and cotton washing); 250 µg/m3 (waste houses); 375 µg/m3 (slashing and weaving) — all 8-hr TWA lint-free respirable dust

**PEL:** 200 µg/m3 (yarn manufacturing and cotton washing); 500 µg/m3 (waste house operations)

**Surveillance trigger:** All employees exposed to cotton dust (initial examination for all); annual surveillance for employees exposed above the action level; every two years for employees at or below the action level

**Exam frequency:** At least annually for employees exposed above the action level; at least every two years for employees at or below the action level; every six months for employees with specified FEV1 decrements

**Record retention:** At least 20 years

> (D) Any employee medical complaints related to exposure to cotton dust ; (E) A copy of this standard and its appendices, except that the employer may keep one copy of the standard and the appendices for all employees , provided that he references the standard and appendices in the medical surveillance record of each employee ; and (F) A copy of the information provided to the physician as required by paragraph (h)(4) of this section . (iii) The employer shall maintain this record for at least 20 years. (3) Availability. (i) The employer shall make all records required to be maintained by paragraph (k) of this section available to the Assistant Secretary and the Director for examination and copying. (ii) Employee exposure measurement records and <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=8e410213f86c0ef574a42c60b461f826&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1043>

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1043>

Cotton dust — OSHA medical surveillance trigger thresholds by substance


**Substance:** Ethylene oxide

**CFR section:** 1910.1047

**Action level:** 0.5 ppm calculated as an eight (8)-hour time-weighted average

**PEL:** one (1) part EtO per million parts of air (1 ppm) as an 8-hour time-weighted average (8-hour TWA); 5 parts of EtO per million parts of air (5 ppm) as averaged over a sampling period of fifteen (15) minutes

**Surveillance trigger:** all employees who are or may be exposed to EtO at or above the action level, without regard to the use of respirators, for at least 30 days a year

**Exam frequency:** Prior to assignment; at least annually each employee exposed at or above the action level for at least 30 days in the past year; at termination of employment or reassignment

**Record retention:** exposure records: at least thirty (30) years; medical records: duration of employment plus thirty (30) years

> 1910.1047 Ethylene oxide." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1047>

Ethylene oxide — OSHA medical surveillance trigger thresholds by substance


**Substance:** Formaldehyde

**CFR section:** 1910.1048

**Action level:** 0.5 part formaldehyde per million parts of air (0.5 ppm) calculated as an eight (8)-hour time-weighted average (TWA) concentration

**PEL:** 0.75 parts formaldehyde per million parts of air (0.75 ppm) as an 8-hour TWA; 2 ppm STEL

**Surveillance trigger:** all employees exposed to formaldehyde at concentrations at or exceeding the action level or exceeding the STEL

**Exam frequency:** prior to assignment to a job where formaldehyde exposure is at or above the action level or above the STEL and annually thereafter

**Record retention:** Exposure records and determinations: at least 30 years; Medical records: duration of employment plus 30 years

> <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=d75fccdc8250228b94fecda509956f75&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1048> Medical surveillance —(1) Employees covered . (i) The employer shall institute medical surveillance programs for all employees exposed to formaldehyde at concentrations at or exceeding the action level or exceeding the STEL . (ii) The employer shall make medical surveillance available for employees who develop signs and symptoms of overexposure to formaldehyde and for all employees exposed to formaldehyde in emergencies . When determining whether an employee may be experiencing signs and symptoms of possible overexposure to formaldehyde , the employer may rely on the evidence that signs and symptoms associated with formaldehyde exposure will occur only in exceptional circumstances when <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=6ebae100a8ab33b94c99de81c9d6765e&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1048> airborne exposure is less than 0.1 ppm and when formaldehyde is present in material in concentrations less than 0.1 percent. (2) Examination by a physician. All medical procedures, including administration of medical disease questionnaires, shall be performed by or under the supervision of a licensed physician and shall be provided without cost to the employee , without loss of pay, and at a reasonable time and place. (3) Medical disease questionnaire. The employer shall make the following medical surveillance available to employees prior to assignment to a job where formaldehyde exposure is at or above the action level or above the STEL and annually thereafter.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1048>

Formaldehyde — OSHA medical surveillance trigger thresholds by substance


**Substance:** Hazardous waste operations and emergency response (HAZWOPER)

**CFR section:** 1910.120

**Action level:** none defined

**PEL:** none defined

**Surveillance trigger:** Employees exposed to hazardous substances or health hazards at or above the PEL (or published exposure levels if no PEL) for 30 days or more per year; employees who wear a respirator for 30 days or more per year; employees who are injured or develop signs or symptoms from overexposure; members of HAZMAT teams

**Exam frequency:** Prior to assignment; at least once every twelve months unless physician believes a longer interval (not greater than biennially) is appropriate; at termination if no exam within last six months; as soon as possible after emergency incident or development of signs or symptoms

**Record retention:** Retained for the period specified and meeting the criteria of 29 CFR 1910.1020

> All employees who are or may be exposed to hazardous substances or health hazards at or above the permissible exposure limits or, if there is no permissible exposure limit , above the published exposure levels for these substances , without regard to the use of respirators , for 30 days or more a year

Source: <https://www.law.cornell.edu/cfr/text/29/1910.120>

Hazardous waste operations and emergency response (HAZWOPER) — OSHA medical surveillance trigger thresholds by substance

action_level, cfr_section, exam_frequency, pel, record_retention, substance, surveillance_trigger


**Substance:** Hexavalent chromium

**CFR section:** 1910.1026

**Action level:** 2.5 micrograms per cubic meter of air (2.5 µgm/m3) calculated as an 8-hour time-weighted average (TWA)

**PEL:** 5 micrograms per cubic meter of air (5 µgm/m3), calculated as an 8-hour time-weighted average (TWA)

**Surveillance trigger:** Who are or may be occupationally exposed to chromium (VI) at or above the action level for 30 or more days a year; experiencing signs or symptoms of the adverse health effects associated with chromium (VI) exposure; or exposed in an emergency

**Exam frequency:** Within 30 days after initial assignment; annually; within 30 days after PLHCP written medical opinion recommends additional examination; whenever employee shows signs or symptoms; within 30 days after emergency exposure

**Record retention:** maintained and made available in accordance with 29 CFR 1910.1020

> <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=6af9a0e4b2ea72786a9cf387077af7a7&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1026> Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor , or designee. Chromium (VI) [hexavalent chromium or Cr(VI)] means chromium with a valence of positive six, in any form and in any compound.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1026>

Hexavalent chromium — OSHA medical surveillance trigger thresholds by substance


**Substance:** Inorganic arsenic

**CFR section:** 1910.1018

**Action level:** 5 micrograms per cubic meter of air (5 µg/m3)

**PEL:** 10 micrograms per cubic meter of air (10 µg/m3) as determined as an average over an 8-hour period

**Surveillance trigger:** all employees who are or will be exposed above the action level, without regard to the use of respirators, at least 30 days per year; and all employees who have been exposed above the action level for 30 days or more per year for a total of 10 years or more

**Exam frequency:** annually (for employees 45 years of age or less with fewer than 10 years exposure over the action level); every 6 months (for employees over 45 years old or with more than 10 years exposure over the action level)

**Record retention:** at least 40 years or for the duration of employment plus 20 years, whichever is longer

> 1910.1018 Inorganic arsenic." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1018>

Inorganic arsenic — OSHA medical surveillance trigger thresholds by substance


**Substance:** Lead

**CFR section:** 1910.1025

**Action level:** an airborne concentration of lead of 30 micrograms per cubic meter of air (30 µg/m3) averaged over an 8-hour period

**PEL:** fifty micrograms per cubic meter of air (50 µg/m3) averaged over an 8-hour period

**Surveillance trigger:** all employees who are or may be exposed at or above the action level for more than 30 days per year

**Exam frequency:** at least every 6 months (biological monitoring); at least annually for each employee for whom a blood lead level at any time during the preceding 12 months indicated at or above 40 µg/100 g

**Record retention:** at least 40 years, or for the duration of employment plus 20 years, whichever is longer

> (iv) The employer shall maintain or assure that the physician maintains those medical records for at least 40 years, or for the duration of employment plus 20 years, whichever is longer. (3) Medical removals. (i) The employer shall establish and maintain an accurate record for each employee removed from current exposure to lead pursuant to paragraph (k) of this section . (ii) Each record shall include: (A) The name of the employee ; (B) The date on each occasion that the employee was removed from current exposure to lead as <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=9a247d3e15cf2da7828b85ab1fc149e2&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1025> well as the corresponding date on which the employee was returned to his or her former job status;

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1025>

Lead — OSHA medical surveillance trigger thresholds by substance


**Substance:** Methylene chloride

**CFR section:** 1910.1052

**Action level:** 12.5 parts per million (ppm) calculated as an eight (8)-hour time-weighted average (TWA)

**PEL:** twenty-five parts of MC per million parts of air (25 ppm) as an 8-hour TWA; one hundred and twenty-five parts of MC per million parts of air (125 ppm) as determined over a sampling period of fifteen minutes

**Surveillance trigger:** at or above the action level on 30 or more days per year, or above the 8-hour TWA PEL or the STEL on 10 or more days per year

**Exam frequency:** Initial before assignment; for employees 45 years of age or older, within 12 months of initial or any subsequent surveillance; for employees younger than 45 years of age, within 36 months of initial or any subsequent surveillance; at termination or reassignment if six months or more have elapsed since last surveillance

**Record retention:** duration of employment plus thirty (30) years

> <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=127ec2eccc47b064b95580991711b3ce&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1052> Scope and application . This section applies to all occupational exposures to methylene chloride (MC), <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=43beba05935babbe7c9b66c8d60a244e&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1052> Chemical Abstracts <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=7ab99fc89fa38fc3f0ffa4aeb1a0ae4b&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1052> Service Registry Number 75-09-2, in general industry, construction and shipyard employment. (b) Definitions. For the purposes of this section , the following definitions shall apply: Action level means a concentration of airborne MC of 12.5 parts per million (ppm) calculated as an eight (8)-hour time-weighted average (TWA).

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1052>

Methylene chloride — OSHA medical surveillance trigger thresholds by substance


**Substance:** Methylenedianiline

**CFR section:** 1910.1050

**Action level:** 5 ppb as an eight (8)-hour time-weighted average

**PEL:** ten parts per billion (10 ppb) as an 8-hour time-weighted average; STEL of 100 ppb

**Surveillance trigger:** Employees exposed at or above the action level for 30 or more days per year; employees who are subject to dermal exposure to MDA for 15 or more days per year; employees who have been exposed in an emergency situation

**Exam frequency:** within 150 days of the effective date or before the time of initial assignment; at least annually following the initial examination

**Record retention:** exposure records: at least 30 years; medical records: at least the duration of employment plus 30 years

> 1910.1050 Methylenedianiline." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1050>

Methylenedianiline — OSHA medical surveillance trigger thresholds by substance


**Substance:** Noise (occupational noise exposure)

**CFR section:** 1910.95

**Action level:** 85 dBA 8-hour TWA

**PEL:** 90 dBA (8-hour TWA) per Table G-16

**Surveillance trigger:** Exposure equal to or exceeding an 8-hour time-weighted average sound level (TWA) of 85 decibels measured on the A scale (slow response) or, equivalently, a dose of fifty percent

**Exam frequency:** Baseline audiogram within 6 months of first exposure at or above action level; at least annually thereafter for each employee exposed at or above an 8-hour TWA of 85 decibels

**Record retention:** Noise exposure measurement records: two years; audiometric test records: duration of the affected employee's employment

> The employer shall establish and maintain an audiometric testing program as provided in this paragraph by making audiometric testing available to all employees whose exposures equal or exceed an 8-hour time-weighted average of 85 decibels.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.95>

Noise (occupational noise exposure) — OSHA medical surveillance trigger thresholds by substance

cfr_section, exam_frequency, pel, record_retention, substance, surveillance_trigger


**Substance:** Respirable crystalline silica

**CFR section:** 1910.1053

**Action level:** 25 µg/m3, calculated as an 8-hour TWA

**PEL:** 50 µg/m3, calculated as an 8-hour TWA

**Surveillance trigger:** each employee who will be occupationally exposed to respirable crystalline silica at or above the action level for 30 or more days per year

**Exam frequency:** Initial (baseline) examination within 30 days after initial assignment; periodic examinations at least every three years

**Record retention:** maintained and made available in accordance with 29 CFR 1910.1020

> <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=d75fccdc8250228b94fecda509956f75&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1053> Medical surveillance —(1) General. (i) The employer shall make medical surveillance available at no cost to the employee , and at a reasonable time and place, for each employee who will be occupationally exposed to respirable crystalline silica at or above the action level for 30 or more days per year.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1053>

Respirable crystalline silica — OSHA medical surveillance trigger thresholds by substance


**Substance:** Respiratory protection

**CFR section:** 1910.134

**Action level:** not applicable (equipment standard)

**PEL:** not applicable (equipment standard)

**Surveillance trigger:** Before the employee is fit tested or required to use the respirator in the workplace

**Exam frequency:** Prior to initial use; additional evaluations if employee reports medical signs or symptoms related to ability to use a respirator, or if workplace conditions change

**Record retention:** Records of medical evaluations required by this section must be retained and made available in accordance with 29 CFR 1910.1020

> 1910.134 Respiratory protection." /> 29 CFR §

Source: <https://www.law.cornell.edu/cfr/text/29/1910.134>

Respiratory protection — OSHA medical surveillance trigger thresholds by substance


**Substance:** Vinyl chloride

**CFR section:** 1910.1017

**Action level:** 0.5 ppm averaged over an 8-hour work day

**PEL:** 1 ppm averaged over any 8-hour period; 5 ppm averaged over any period not exceeding 15 minutes

**Surveillance trigger:** exposed, without regard to the use of respirators, to vinyl chloride in excess of the action level

**Exam frequency:** at least annually (examinations must be provided in accordance with this paragraph at least annually)

**Record retention:** duration of the employment of each employee plus 20 years, or 30 years, whichever is longer

> (ii) [Reserved] (iii) Medical records shall be maintained for the duration of the employment of each employee plus 20 years, or 30 years, whichever is longer. (n) The employer must, within 15 working days after the receipt of the results of any monitoring performed under this section , notify each affected employee of these results and the steps being taken to reduce exposures within the permissible exposure limit either individually in writing or by posting the results in an appropriate <https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=529ee1d7fa3659b1bbc5b4eaade8ec90&term_occur=999&term_src=Title:29:Subtitle:B:Chapter:XVII:Part:1910:1910.1017> location that is accessible to affected employees. Appendix A to <https://www.law.cornell.edu/cfr/text/29/1910.1017> § 1910.1017 —Supplementary Medical Information When required tests under paragraph (k)(1) of this section show abnormalities, the tests should be repeated as soon as practicable, preferably within 3 to 4 weeks. If tests remain abnormal, consideration should be given to withdrawal of the employee from contact with vinyl chloride , while a more comprehensive examination is made.

Source: <https://www.law.cornell.edu/cfr/text/29/1910.1017>

Vinyl chloride — OSHA medical surveillance trigger thresholds by substance