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Hydrogen chloride																				Related Pages
Synonyms & Trade Names
			Anhydrous hydrogen chloride, Aqueous hydrogen chloride, Hydrochloric 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)

FormulaHCl
	Conversion
			1 ppm = 1.49 mg/m3
	IDLH
			50 ppmSee: 7647010

Exposure Limits
			NIOSH RELC 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.]													
										
Molecular Weight36.5	
	Boiling Point-121°F
	Freezing Point-174°F
	Solubility(86°F): 67%
	Vapor Pressure40.5 atm
	Ionization Potential12.74 eV											
Flash PointNA
	Upper Explosive LimitNA
	Lower Explosive LimitNA
	Relative Gas Density1.27
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 canisterAny appropriate escape-type, self-contained breathing apparatus
				Important additional information about respirator selection
See also
			INTRODUCTION
					  ICSC CARD: 0163
					  MEDICAL TESTS: 0116

			
							

			Page last reviewed:  October 30, 2019						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Pocket Guide to Chemical Hazards
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Appendices
A – NIOSH Potential Occupational Carcinogens
B – Thirteen OSHA-Regulated Carcinogens
C – Supplementary Exposure Limits
D – Substances with No Established RELs
E – OSHA Respirator Requirements for Selected Chemicals
F – Miscellaneous Notes
G – 1989 Air Contaminants Update Project: Exposure Limits NOT in Effect
Type C & CE – Definitions for Type C and Type CE Respirators
Personal Protection and Sanitation Codes
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