Phthalic anhydride
For Phthalic anhydride, cas no. is 85-44-9; pel (ppm) is 2; pel (mg/m³) is 12, verified against its source on 2026-08-05.
- Substance
- Phthalic anhydride
- CAS No.
- 85-44-9
- PEL (ppm)
- 2
- PEL (mg/m³)
- 12
What the source says
Phthalic anhydride | 85-44-9 | 2 | 12 | - |
— osha.gov, retrieved 2026-08-05
Sources disagree
More than one authority states this, and they do not state the same thing. Both are reproduced with the source each came from — deciding between them is yours, not ours.
PEL (ppm)
osha.gov says pel (ppm) is 2, as of 2026-08-05.
Phthalic anhydride | 85-44-9 | 2 | 12 | - |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (ppm) is 1, as of 2026-08-05.
85449 | | Phthalic anhydride | 1 | 6
https://www.dir.ca.gov/title8/5155.html
PEL (mg/m³)
osha.gov says pel (mg/m³) is 12, as of 2026-08-05.
Phthalic anhydride | 85-44-9 | 2 | 12 | - |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (mg/m³) is 6, as of 2026-08-05.
85449 | | Phthalic anhydride | 1 | 6
Sources
- osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
- dir.ca.govhttps://www.dir.ca.gov/title8/5155.html