NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

1,1-Dimethylhydrazine

CAS
57-14-7

(CH3)2NNH2

RTECS
MV2450000
Synonyms & Trade Names

Dimazine, DMH, UDMH, Unsymmetrical dimethylhydrazine
DOT ID & Guide
1163 / 131

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]
IDLH
Ca [15 ppm] See: 57147
Conversion
1 ppm = 2.46 mg/m3
Physical Description
Colorless liquid with an ammonia- or fish-like odor.
MW: 60.1
BP: 147°F
FRZ: -72°F
Sol: Miscible
VP: 103 mmHg
IP: 8.05 eV

Sp.Gr: 0.79
Fl.P: 5°F
UEL: 95%
LEL: 2%

Class IB Flammable Liquid: Fl.P. below 73F and BP at or above 100F.
Incompatibilities & Reactivities

Oxidizers, halogens, metallic mercury, fuming nitric acid, hydrogen peroxide [Note: May ignite SPONTANEOUSLY in contact with oxidizers.]
Measurement Methods
NIOSH 3515
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 (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
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]
See also: INTRODUCTION   See ICSC CARD: 0147   See MEDICAL TESTS: 0083