Reference Source

N-Ethylmorpholine — workplace exposure limit

What is the pel (ppm) for N-Ethylmorpholine — workplace exposure limit?

For N-Ethylmorpholine, pel (ppm) is 20; pel (mg/m³) is 94; cas no. is 100-74-3, verified against its source on 2026-08-05.

N-Ethylmorpholine | 100-74-3 | 20 | 94 | X |

osha.gov, retrieved 2026-08-05

20
The most of this substance workplace air may legally contain, averaged over an 8-hour shift — OSHA's permissible exposure limit (PEL), in parts per million, from the agency's own table row quoted below. Where federal OSHA and Cal/OSHA disagree, both limits are stated, each with its own agency's table row as evidence. NIOSH's number, where there is one, is shown separately: it is a recommended limit, not a legal one, and it is often the strictest of the three.
Sourceosha.gov
Verified
Review by
DatasetUS workplace chemical exposure limits: federal OSHA, Cal/OSHA and NIOSH, side by side
Substance
N-Ethylmorpholine verified
CAS No.
100-74-3 verified
PEL (ppm)
20 verified
PEL (mg/m³)
94 verified
NIOSH REL (ppm)
TWA 5 per cdc.gov
NIOSH REL (mg/m³)
23 per cdc.gov

What cdc.gov says

NIOSH REL TWA 5 ppm (23 mg/m3) [skin]

cdc.gov, retrieved 2026-09-08

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 20, as of 2026-08-05.

N-Ethylmorpholine | 100-74-3 | 20 | 94 | X |

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

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

100743 | S | N-Ethylmorpholine; 4-ethyl-1, 4-tetrahydrooxazine | 5 | 23

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

PEL (mg/m³)

osha.gov says pel (mg/m³) is 94, as of 2026-08-05.

N-Ethylmorpholine | 100-74-3 | 20 | 94 | X |

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

dir.ca.gov says pel (mg/m³) is 23, as of 2026-08-05.

100743 | S | N-Ethylmorpholine; 4-ethyl-1, 4-tetrahydrooxazine | 5 | 23

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

Sources

Last verified against source: . Due for re-check by . This page as Markdown · OKF bundle · full dataset as JSON.

What is the OSHA exposure limit for this substance?Find the exposure limit for a substance in workplace air — federal OSHA, California and NIOSH, side by side.