Respirable crystalline silica
For Respirable crystalline silica, cfr section is 1910.1053; action level is 25 µg/m3, calculated as an 8-hour TWA; pel is 50 µg/m3, calculated as an 8-hour TWA; surveillance trigger is 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 is Initial (baseline) examination within 30 days after initial assignment; periodic examinations at least every three years, recorded from its source on 2026-08-12.
- Substance
- Respirable crystalline silica verified
- CFR section
- 1910.1053 verified
- 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 verified
- 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
What the source says
<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.
— law.cornell.edu, retrieved 2026-08-12
Source
- law.cornell.eduhttps://www.law.cornell.edu/cfr/text/29/1910.1053