1. OSHA Occupational Chemical Database
  2. MORPHOLINE
Label abbreviations descriptions

MORPHOLINE†

Chemical Identification
Chemical Identification
CAS # 110-91-8
Formula
 

C₄H₉NO
Synonyms
 

diethylene imidoxide; diethylene oximide; tetrahydro-1,4-oxazine; tetrahydro-p-oxazine
Physical Properties
Physical Properties
Physical description Colorless liquid with a weak, ammonia- or fish-like odor.
Boiling point 264°F Molecular weight 87.12
Freezing point/melting point 23.2°F Vapor pressure 6 mmHg
Flash point 98°F (open cup) Vapor density 3
Specific gravity 1.007 Ionization potential 8.88 eV
Lower explosive limit (LEL) 1.8% Upper explosive limit (UEL) 10.8%
NFPA health rating 3 NFPA fire rating 3
NFPA reactivity rating 1 NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs
Monitoring Methods Used by OSHA
Monitoring Methods Used by OSHA
Analyte code (IMIS no.) 1797
Sampling group
Sampler/Sampling media XAD-7 tube (80/40 mg) coated with 10% NBD chloride [SKC 226-96]
Sampling time*
 

 
Sampling volume (TWA)*
 

10 L
Sampling flow rate (TWA)*
 

0.1 L/min
Sampling volume (STEL/Peak/C)*
 

 
Sampling flow rate (STEL/Peak/C)*
 

 
Analytical method instruments GC-FID
Method reference OSHA PV2123 (partially validated)
Notes
 

 
Special requirements
 

 

* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Wipe Method
Wipe Method
Sampler/Sampling media
 

 
Bulk Method
Bulk Method
 

 
On-Site Screening Techniques
On-Site Screening Techniques
Device Infrared spectrophotometer Infrared spectrophotometer
Model/Type Miran 1A & 1B Miran 103
Sampling information
(see manufacturer instructions) 		0.7 ppm@9 µm 0-100 ppm@9 µm
Exposure Limits
Exposure Limits
OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
NIOSH REL
Up to 10-hour TWA
(ST) STEL
(C) Ceiling
ACGIH TLV©
8-hour TWA
(ST) STEL
(C) Ceiling
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
PEL-TWA
 

20 ppm (70 mg/m³)

 REL-TWA
 

20 ppm (70 mg/m³)

 TLV-TWA
 

20 ppm [1992]

 PEL-TWA
 

20 ppm (70 mg/m³)
PEL-STEL
 

 

 REL-STEL
 

30 ppm (105 mg/m³)

 TLV-STEL
 

 

 PEL-STEL
 

30 ppm (105 mg/m³)
PEL-C
 

 

 REL-C
 

 

 TLV-C
 

 

 PEL-C
 

 
Skin notation
 

Y

 Skin notation
 

Y

 Skin notation
 

Y

 Skin notation
 

Y
Notes:
 

See 29 CFR 1910.1000 Table Z-1.

 Notes:
 

 

 Notes:
 

 

 Notes:
 

 
Health factors:  See NIH-NLM PubChem. IDLH
 

1400 ppm
Carcinogenic classifications: IARC-3, TLV-A4 Notes:
 

10% of LEL
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
 

 
Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Morpholine

NIOSH: Pocket Guide to Chemical Hazards - Morpholine

Literature References

 
  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Morpholine. See annual publication for most recent information.
  • [No authors listed]: Morpholine [18 KB PDF, 4 pages]. IARC Monogr. Eval. Carcinog. Risks Hum. 47: 199-213, 1989.
  • Pohanish, R.P. (editor): Morpholine. In, Sittig’s Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1639-1641.

Last Updated Date : 01/28/2021