Reference Source

Carbon dioxide

For Carbon dioxide, cas no. is 124-38-9; pel (ppm) is 5000; pel (mg/m³) is 9000, verified against its source on 2026-08-05.

Substance
Carbon dioxide
CAS No.
124-38-9
PEL (ppm)
5000
PEL (mg/m³)
9000
Sourceosha.gov
Verified2026-08-05
Review by2027-08-05
DatasetUS workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side

What the source says

Carbon dioxide | 124-38-9 | 5000 | 9000 | - |

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 5000, as of 2026-08-05.

Carbon dioxide | 124-38-9 | 5000 | 9000 | - |

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

dir.ca.gov says pel (ppm) is 5,000, as of 2026-08-05.

124389 | | Carbon dioxide | 5,000 | 9,000 | | 30,000 | 54,000

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

PEL (mg/m³)

osha.gov says pel (mg/m³) is 9000, as of 2026-08-05.

Carbon dioxide | 124-38-9 | 5000 | 9000 | - |

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

dir.ca.gov says pel (mg/m³) is 9,000, as of 2026-08-05.

124389 | | Carbon dioxide | 5,000 | 9,000 | | 30,000 | 54,000

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

Sources

Last verified against source: 2026-08-05. Scheduled for re-check by: 2027-08-05. This page as Markdown · OKF concept · full dataset as JSON.