# Propylene glycol dinitrate — workplace exposure limit For Propylene glycol dinitrate, niosh rel (ppm) is TWA 0.05; niosh rel (mg/m³) is 0.3; cas no. is 6423-43-4, verified against its source on 2026-09-08. - **Substance:** Propylene glycol dinitrate _(verified: appears in its own passage below)_ - **CAS No.:** 6423-43-4 _(verified: appears in its own passage below)_ - **NIOSH REL (ppm):** TWA 0.05 _(verified: appears in the quote below)_ - **NIOSH REL (mg/m³):** 0.3 _(verified: appears in the quote below)_ - **PEL (ppm):** 0.05 _(per dir.ca.gov, not stated by the source above)_ - **PEL (mg/m³):** 0.3 _(per dir.ca.gov, not stated by the source above)_ ## What the source says > NIOSH REL TWA 0.05 ppm (0.3 mg/m3) [skin] ## 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 - Propylene glycol dinitrate ### CAS No. > CAS No. 6423-43-4 ## What dir.ca.gov says > 6423434 | S | Propylene glycol dinitrate; PGDN | 0.05 | 0.3 Source: https://www.dir.ca.gov/title8/5155.html ## Source - https://www.cdc.gov/niosh/npg/npgd0535.html - https://www.dir.ca.gov/title8/5155.html Last verified: 2026-09-08. Review by: 2027-08-05. Part of [US workplace chemical exposure limits: federal OSHA, Cal/OSHA and NIOSH, side by side](https://referencesource.org/workplace-exposure-limits/).