Perchloroethylene — CAS 127184 — workplace exposure limit

What is the pel (ppm) for Perchloroethylene — CAS 127184 — workplace exposure limit?

For Perchloroethylene, pel (ppm) is 25; pel (mg/m³) is 170; ceiling is 300 ppm; ceiling notation is a ceiling value in addition to the TWA values; stel (ppm) is 100; stel (mg/m³) is 685; cas no. is 127184, verified against its source on 2026-09-29.

127184 | | Perchloroethylene | 25 | 170 | 300 ppm | 100 | 685

— dir.ca.gov, retrieved 2026-09-28

The most of this substance workplace air may legally contain, averaged over an 8-hour shift — OSHA's permissible exposure limit (PEL), in parts per million, from the agency's own table row quoted below. Where federal OSHA and Cal/OSHA disagree, both limits are stated, each with its own agency's table row as evidence. NIOSH's number, where there is one, is shown separately: it is a recommended limit, not a legal one, and it is often the strictest of the three.

Sourcedir.ca.gov

Verified2026-09-29

Review by2027-08-05

DatasetUS workplace chemical exposure limits: federal OSHA, Cal/OSHA and NIOSH, side by side

Substance: Perchloroethylene verified
CAS No.: 127184 verified
PEL (ppm): 25 verified
PEL (mg/m³): 170 verified
Ceiling: 300 ppm verified
Ceiling notation: a ceiling value in addition to the TWA values verified
STEL (ppm): 100 verified
STEL (mg/m³): 685 verified
NIOSH REL, as stated: Ca Minimize workplace exposure concentrations. See Appendix A per cdc.gov

Where each value comes from

The value above is stated away from the sentence quoted with the answer, so the passage that states it is shown here too.

Ceiling notation

A numerical entry in this column represents a ceiling value in addition to the TWA values.

— all from dir.ca.gov, retrieved 2026-09-28

What osha.gov says

Perchloroethylene (Tetrachloroethylene) | 127-18-4 | - | (2) | - |

— osha.gov, retrieved 2026-08-05

What cdc.gov says

NIOSH REL Ca Minimize workplace exposure concentrations. See Appendix A

— cdc.gov, retrieved 2026-09-08

Substance

CDC - NIOSH Pocket Guide to Chemical Hazards - Tetrachloroethylene

CAS No.

CAS No. 127-18-4

The same source also states

127184 | | Tetrachloroethylene; see Perchloroethylene

— dir.ca.gov, retrieved 2026-08-05

Sources

dir.ca.govhttps://www.dir.ca.gov/title8/5155.html
osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
cdc.govhttps://www.cdc.gov/niosh/npg/npgd0599.html

Last verified against source: 2026-09-29. Due for re-check by 2027-08-05. This page as Markdown · OKF bundle · full dataset as JSON.

What is the OSHA exposure limit for this substance?Find the exposure limit for a substance in workplace air — federal OSHA, California and NIOSH, side by side.