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Hydrogen chloride

Synonyms & Trade Names
Anhydrous hydrogen chloride; Aqueous hydrogen chloride (i.e., Hydrochloric acid, Muriatic acid) [Note: Often used in an aqueous solution.]
CAS No.
7647-01-0
RTECS No.
MW4025000
DOT ID & Guide
1050 125 (anhydrous)
1789 157 (solution)
Formula
HCl
Conversion
1 ppm = 1.49 mg/m3
IDLH
50 ppm
See: 7647010
Exposure Limits
NIOSH REL
: C 5 ppm (7 mg/m3)
OSHA PEL
: C 5 ppm (7 mg/m3)
Measurement Methods

NIOSH 7903;
OSHA ID174SG
See: NMAM or OSHA Methods
Physical Description
Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.]
MW:
36.5
BP:
-121°F
FRZ:
-174°F		 Sol(86°F): 67%
VP:
40.5 atm
IP:
12.74 eV
Fl.P:
NA
UEL:
NA
LEL:
NA
RGasD:
1.27
Nonflammable Gas
Incompatibilities & Reactivities
Hydroxides, amines, alkalis, copper, brass, zinc [Note: Hydrochloric acid is highly corrosive to most metals.]
Exposure Routes
inhalation, ingestion (solution), skin and/or eye contact
Symptoms
irritation nose, throat, larynx; cough, choking; dermatitis; solution: eye, skin burns; liquid: frostbite; in animals: laryngeal spasm; pulmonary edema
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact (solution)/Frostbite
Eyes: Prevent eye contact/Frostbite
Wash skin: When contaminated (solution)
Remove: When wet or contaminated (solution)
Change: No recommendation
Provide: Eyewash (solution), Quick drench (solution), Frostbite wash
First Aid
(See procedures)
Eye: Irrigate immediately (solution)/Frostbite
Skin: Water flush immediately (solution)/Frostbite
Breathing: Respiratory support
Swallow: Medical attention immediately (solution)
Respirator Recommendations

NIOSH/OSHA

Up to 50 ppm:
(APF = 10) Any chemical cartridge 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 = 25) Any powered, air-purifying respirator with cartridge(s) 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 acid gas canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0163   See MEDICAL TESTS: 0116
 

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