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1,1-Dimethylhydrazine

Synonyms & Trade Names
Dimazine, DMH, UDMH, Unsymmetrical dimethylhydrazine
CAS No.
57-14-7
RTECS No.
DOT ID & Guide
1163 131
Formula
(CH₃)₂NNH₂
Conversion
1 ppm = 2.46 mg/m3
IDLH
Ca [15 ppm]
See: 57147
Exposure Limits
NIOSH REL
Ca C 0.06 ppm (0.15 mg/m3) [2-hr] See Appendix A
OSHA PEL
TWA 0.5 ppm (1 mg/m3) [skin]
Measurement Methods
NIOSH 3515
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with an ammonia- or fish-like odor.
Molecular Weight
60.1
Boiling Point
147°F
Freezing Point
-72°F
Solubility
Miscible
Vapor Pressure
103 mmHg
Ionization Potential
8.05 eV
Specific Gravity
0.79
Flash Point
5°F
Upper Explosive Limit
95%
Lower Explosive Limit
2%
Class IB Flammable Liquid: Fl.P. below 73°F and BP at or above 100°F.
Incompatibilities & Reactivities
Oxidizers, halogens, metallic mercury, fuming nitric acid, hydrogen peroxide [Note: May ignite SPONTANEOUSLY in contact with oxidizers.]
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin; choking, chest pain, dyspnea (breathing difficulty); drowsiness; nausea; anoxia; convulsions; liver injury; [potential occupational carcinogen]
Target Organs
central nervous system, liver, gastrointestinal tract, blood, respiratory system, eyes, skin
Cancer Site
[in animals: tumors of the lungs, liver, blood vessels & intestines]
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
Change:No recommendation
Provide:Eyewash, Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

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: 0147   MEDICAL TESTS: 0083
Page last reviewed: October 30, 2019