# Hexafluoroacetone — workplace exposure limit

For Hexafluoroacetone, niosh rel (ppm) is TWA 0.1; niosh rel (mg/m³) is 0.7; cas no. is 684-16-2, verified against its source on 2026-09-08.

- **Substance:** Hexafluoroacetone _(verified: appears in its own passage below)_
- **CAS No.:** 684-16-2 _(verified: appears in its own passage below)_
- **NIOSH REL (ppm):** TWA 0.1 _(verified: appears in the quote below)_
- **NIOSH REL (mg/m³):** 0.7 _(verified: appears in the quote below)_
- **PEL (ppm):** 0.1 _(per dir.ca.gov, not stated by the source above)_
- **PEL (mg/m³):** 0.7 _(per dir.ca.gov, not stated by the source above)_

## What the source says

> NIOSH REL TWA 0.1 ppm (0.7 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 - Hexafluoroacetone

### CAS No.

> CAS No. 684-16-2

## What dir.ca.gov says

> 684162 | S | Hexafluoroacetone; 1,1,1,3,3,3-hexafluoro-2-propanone | 0.1 | 0.7

Source: https://www.dir.ca.gov/title8/5155.html

## Source

- https://www.cdc.gov/niosh/npg/npgd0319.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/).