NIOSH Pocket Guide to Chemical Hazards

Formalin (as formaldehyde)


Synonyms & Trade Names
Formaldehyde solution [Note: Formalin is an aqueous solution that is 37% formaldehyde by weight; inhibited solutions usually contain 6-12% methyl alcohol. Also see specific listings for Formaldehyde and Methyl alcohol.]
DOT ID & Guide
1198 132
2209 132


NIOSH REL: Ca TWA 0.016 ppm C 0.1 ppm [15-minute] See Appendix A
OSHA PEL: [1910.1048] TWA 0.75 ppm ST 2 ppm
IDLH Ca [20 ppm] See: IDLH INDEX Conversion
Physical Description
Colorless liquid with a pungent odor.
MW: Varies
BP: 214°F
FRZ: ?
Sol: Miscible
VP: 1 mmHg
IP: ?

Sp.Gr(77°F): 1.08
Fl.P: 185°F
UEL: 73%
LEL: 7%

Class IIIA Combustible Liquid: Fl.P. at or above 140F and below 200F.
Incompatibilities & Reactivities
Strong oxidizers, alkalis & acids; phenols; urea; oxides; isocyanates; caustics; anhydrides
Measurement Methods
NIOSH 2016, 2541, 3500, 3800; OSHA ID205, 52
See: NMAM or OSHA Methods
Personal Protection & Sanitation (See protection)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: No recommendation
Provide: Eyewash, Quick drench
First Aid (See procedures)
Eye: Irrigate immediately
Skin: Water flush promptly
Breathing: Respiratory support
Swallow: Medical attention immediately
Important additional information about respirator selection
Respirator Recommendations (See Appendix E) NIOSH
At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern/Any appropriate escape-type, self-contained breathing apparatus
Exposure Routes inhalation, ingestion, skin and/or eye contact
Symptoms Irritation eyes, nose, throat, respiratory system; lacrimation (discharge of tears); cough; wheezing, dermatitis; [potential occupational carcinogen]
Target Organs Eyes, skin, respiratory system

Cancer Site [nasal cancer]