Styrene — CAS 100-42-5 — workplace exposure limit

What is the cas no. for Styrene — workplace exposure limit?

For Styrene, cas no. is 100-42-5, verified against its source on 2026-08-05.

Styrene | 100-42-5 | - | (2) | - |

— osha.gov, retrieved 2026-08-05

Substance: Styrene verified
CAS No.: 100-42-5 verified
NIOSH REL (ppm): TWA 50 per cdc.gov
NIOSH REL (mg/m³): 215 per cdc.gov
PEL (ppm): 50 per dir.ca.gov
PEL (mg/m³): 215 per dir.ca.gov
Ceiling: 500 ppm per dir.ca.gov
Ceiling notation: a ceiling value in addition to the TWA values per dir.ca.gov
STEL (ppm): 100 per dir.ca.gov
STEL (mg/m³): 425 per dir.ca.gov

Verified2026-08-05

Review by2027-08-05

NIOSH REL TWA 50 ppm (215 mg/m3) ST 100 ppm (425 mg/m3)

— cdc.gov, retrieved 2026-09-08

Substance

CDC - NIOSH Pocket Guide to Chemical Hazards - Styrene

CAS No.

CAS No. 100-42-5

100425 | S | Styrene (monomer); phenylethylene | 50 | 215 | 500 ppm | 100 | 425

— dir.ca.gov, retrieved 2026-09-28

100425 | | Phenylethylene; see Styrene

— dir.ca.gov, retrieved 2026-08-05

100425 | | Vinylbenzene; see Styrene

— dir.ca.gov, retrieved 2026-08-05

osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
cdc.govhttps://www.cdc.gov/niosh/npg/npgd0571.html
dir.ca.govhttps://www.dir.ca.gov/title8/5155.html

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