# Carbaryl — workplace exposure limit For Carbaryl, niosh rel (mg/m³) is TWA 5; cas no. is 63-25-2, verified against its source on 2026-09-08. - **Substance:** Carbaryl _(verified: appears in its own passage below)_ - **CAS No.:** 63-25-2 _(verified: appears in its own passage below)_ - **NIOSH REL (mg/m³):** TWA 5 _(verified: appears in the quote below)_ ## What the source says > NIOSH REL TWA 5 mg/m3 ## Where each value comes from This source states these in separate places, so each value is shown with the passage that states it. ### Substance > CDC - NIOSH Pocket Guide to Chemical Hazards - Carbaryl ### CAS No. > CAS No. 63-25-2 ## Source - https://www.cdc.gov/niosh/npg/npgd0100.html Last verified: 2026-09-08. Review by: 2027-09-08. Part of [US workplace chemical exposure limits: federal OSHA, Cal/OSHA and NIOSH, side by side](https://referencesource.org/workplace-exposure-limits/).