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Formaldehyde

Synonyms & Trade Names
Methanal, Methyl aldehyde, Methylene oxide
CAS No.
50-00-0
RTECS No.
DOT ID & Guide
Formula
HCHO
Conversion
1 ppm = 1.23 mg/m3
IDLH
Ca [20 ppm]
See: 50000
Exposure Limits
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
Measurement Methods
NIOSH 2016 , 2541 , 3500 , 3800;
OSHA ID205 , 52
See: NMAM or OSHA Methods
Physical Description
Nearly colorless gas with a pungent, suffocating odor. [Note: Often used in an aqueous solution (see specific listing for Formalin).]
Molecular Weight
30.0
Boiling Point
-6°F
Freezing Point
-134°F
Solubility
Miscible
Vapor Pressure
>1 atm
Ionization Potential
10.88 eV
Flash Point
NA (Gas)
Upper Explosive Limit
73%
Lower Explosive Limit
7.0%
Relative Gas Density
1.04
Flammable Gas
Incompatibilities & Reactivities
Strong oxidizers, alkalis & acids; phenols; urea [Note: Pure formaldehyde has a tendency to polymerize. Reacts with HCl to form bis-Chloromethyl ether.]
Exposure Routes
inhalation, skin and/or eye contact
Symptoms
irritation eyes, nose, throat, respiratory system; lacrimation (discharge of tears); cough; wheezing; [potential occupational carcinogen]
Target Organs
Eyes, respiratory system
Cancer Site
[nasal cancer]
Personal Protection/Sanitation
(See protection codes)
Skin:No recommendation
Eyes:Prevent eye contact
Wash skin:No recommendation
Remove:No recommendation
Change:No recommendation
First Aid
(See procedures)
Eye:Irrigate immediately

Breathing:Respiratory support
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

Escape:
(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

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0695   MEDICAL TESTS: 0110
Page last reviewed: October 30, 2019