---
type: threshold
id: diacetone-alcohol-4-hydroxy-4-methyl-2-pentanone
asset: workplace-exposure-limits
title: "Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone) — US workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side"
sources:
  - https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
source_quote: "Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone) | 123-42-2 | 50 | 240 | - |"
generated: true
harvested: 2026-08-05
stale_after: 2027-08-05
substance: "Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone)"
cas_number: "123-42-2"
pel_ppm: "50"
pel_mgm3: "240"
verified: true
---
**Substance:** Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone)

**CAS No.:** 123-42-2

**PEL (ppm):** 50

**PEL (mg/m³):** 240

> Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone) | 123-42-2 | 50 | 240 | - |

Source: <https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1>