1. OSHA Occupational Chemical Database
  2. METHACRYLIC ACID
Label abbreviations descriptions

METHACRYLIC ACID

Chemical Identification
Chemical Identification
CAS # 79-41-4
Formula

C₄H₆O₂
Synonyms

methacrylic acid (glacial); methacrylic acid (inhibited); α-methacrylic acid; 2-methylacrylic acid; 2-methylpropenoic acid
Physical Properties
Physical Properties
Physical description Colorless liquid or solid (below 61°F) with an acrid, repulsive odor.
Boiling point 325°F Molecular weight 86.09
Freezing point/melting point 61°F Vapor pressure 0.7 mmHg
Flash point 171°F (open-cup) Vapor density 2.97
Specific gravity 1.015 at 68°F Ionization potential
Lower explosive limit (LEL) Upper explosive limit (UEL) 2.4%
NFPA health rating 3 NFPA fire rating 2
NFPA reactivity rating 2 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.) M339
Sampling group
Sampler/Sampling media 2 Anasorb 708 tubes in series [SKC 226-30-08]
Sampling time*
 

240 min
Sampling volume (TWA)*
 

24 L
Sampling flow rate (TWA)*
 

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

 
Sampling flow rate (STEL/Peak/C)*
 

 
Analytical method instruments HPLC
Method reference OSHA PV2005 (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
Model/Type
Sampling information
(see manufacturer instructions)
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
 

 

 REL-TWA
 

20 ppm (70 mg/m³)

 TLV-TWA
 

20 ppm [1992]

 PEL-TWA
 

20 ppm (70 mg/m³)
PEL-STEL
 

 

 REL-STEL
 

 

 TLV-STEL
 

 

 PEL-STEL
 

 
PEL-C
 

 

 REL-C
 

 

 TLV-C
 

 

 PEL-C
 

 
Skin notation
 

NA

 Skin notation
 

Y

 Skin notation
 

N

 Skin notation
 

Y
Notes:
 

Not established

 Notes:
 

 

 Notes:
 

 

 Notes:
 

 
Health factors:  See NIH-NLM PubChem. IDLH
Carcinogenic classifications: Not listed Notes:
 

 
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
 

 
Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methacrylic acid

NIOSH: Pocket Guide to Chemical Hazards - Methacrylic acid

Literature References

 
  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methacrylic acid. See annual publication for most recent information.
  • Cosmetic Ingredient Review Expert Panel: Final report of the safety assessment of methacrylic acid. Int. J. Toxicol. 24(Suppl. 5): 33-51, 2005.
  • Greim, H., et al.: Assessment of structurally related chemicals: toxicity and ecotoxicity of acrylic acid and acrylic acid alkyl esters (acrylates), methacrylic acid and methacrylic acid alkyl esters (methacrylates). Chemosphere 31(2): 2637-2659, 1995.
  • Lazarov, A.: Sensitization to acrylates is a common adverse reaction to artificial fingernails. J. Eur. Acad. Dermatol. Venereol. 21(2): 169-174, 2007.
  • Pohanish, R.P. (editor): Methacrylic Acid. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1490-1491.

Last Updated Date : 01/29/2021