# Acrylonitrile — OSHA medical surveillance trigger thresholds by substance

For Acrylonitrile, cfr section is 1910.1045; action level is 1 ppm as an eight (8)-hour time-weighted average; pel is 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 is 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 is At the time of initial assignment, or upon institution of the medical surveillance program; at least annually thereafter, recorded from its source on 2026-08-12.

- **Substance:** Acrylonitrile _(verified: appears in the quote below)_
- **CFR section:** 1910.1045 _(verified: appears in the quote below)_
- **Action level:** 1 ppm as an eight (8)-hour time-weighted average _(verified: appears in the quote below)_
- **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

## What the source says

> <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

Last verified: 2026-08-12. Review by: 2027-02-08.
Part of [OSHA medical surveillance trigger thresholds by substance](https://referencesource.org/osha-medical-surveillance-triggers/).