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Hydrogen fluoride

Synonyms & Trade Names
Anhydrous hydrogen fluoride, Aqueous hydrogen fluoride, HF-A, Hydrofluoric acid
CAS No.
7664-39-3
RTECS No.
DOT ID & Guide
1052 125(anhydrous)
1790 157(solution)
Formula
HF
Conversion
1 ppm = 0.82 mg/m3
IDLH
30 ppm
See: 7664393
Exposure Limits
NIOSH REL
TWA 3 ppm (2.5 mg/m3) C 6 ppm (5 mg/m3) [15-minute]
OSHA PEL
TWA 3 ppm See Appendix G
Measurement Methods
NIOSH 3800 , 7902 , 7903 , 7906;
OSHA ID110
See: NMAM or OSHA Methods
Physical Description
Colorless gas or fuming liquid (below 67°F) with a strong, irritating odor. [Note: Shipped in cylinders.]
Molecular Weight
20.0
Boiling Point
67°F
Freezing Point
-118°F
Solubility
Miscible
Vapor Pressure
783 mmHg
Ionization Potential
15.98 eV
Specific Gravity
1.00 (Liquid at 67°F)
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Relative Gas Density
0.69
Nonflammable Gas
Incompatibilities & Reactivities
Metals, water or steam [Note: Corrosive to metals. Will attack glass and concrete.]
Exposure Routes
inhalation, skin absorption (liquid), ingestion (solution), skin and/or eye contact
Symptoms
irritation eyes, skin, nose, throat; pulmonary edema; eye, skin burns; rhinitis; bronchitis; bone changes
Target Organs
Eyes, skin, respiratory system, bones
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact (liquid)
Eyes:Prevent eye contact (liquid)
Wash skin:When contaminated (liquid)
Remove:When wet or contaminated (liquid)
Change:No recommendation
Provide:Eyewash (liquid), Quick drench (liquid)
First Aid
(See procedures)
Eye:Irrigate immediately (solution/liquid)
Skin:Water flush immediately (solution/liquid)
Breathing:Respiratory support
Swallow:Medical attention immediately (solution)
Respirator Recommendations

NIOSH/OSHA

Up to 30 ppm:
(APF = 10) Any chemical cartridge respirator with cartridge(s) providing protection against the compound of concern*
(APF = 25) Any powered, air-purifying respirator with cartridge(s) providing protection against the compound of concern*
(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
(APF = 10) Any supplied-air respirator*
(APF = 50) Any self-contained breathing apparatus with a full facepiece

Emergency or planned entry into unknown concentrations or IDLH conditions:
(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: 0283   MEDICAL TESTS: 0118
Page last reviewed: October 30, 2019