1. OSHA Occupational Chemical Database
  2. HYDROGEN CHLORIDE
Label abbreviations descriptions

HYDROGEN CHLORIDE†

Chemical Identification
Chemical Identification
CAS # 7647-01-0
Formula

HCl
Synonyms

anhydrous hydrogen chloride; aqueous hydrogen chloride; hydrochloric acid; muriatic acid
Physical Properties
Physical Properties
Physical description Colorless to slightly yellow gas with a pungent, irritating odor.
Boiling point -121°F Molecular weight 36.5
Freezing point/melting point -174°F Vapor pressure 40.5 atm
Flash point Vapor density 1.27
Specific gravity Ionization potential 12.74 eV
Lower explosive limit (LEL) Upper explosive limit (UEL)
NFPA health rating 3 NFPA fire rating 0
NFPA reactivity rating 1 NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs
Monitoring Methods Used by OSHA
Monitoring Methods Used by OSHA
Analyte code (IMIS no.) 1430
Sampling group
Sampler/Sampling media ORBO™ 53 activated silica gel tube [Supelco 20265]
Sampling time*

15 min
Sampling volume (TWA)*

7.5 L
Sampling flow rate (TWA)*

0.5 L/min
Sampling volume (STEL/Peak/C)*
 

 
Sampling flow rate (STEL/Peak/C)*
 

 
Analytical method instruments IC
Method reference OSHA ID-174SG (partially validated)
Notes
 

Submit as a separate sample, however, hydrogen bromide can be analyzed from the same sample. The sample is analyzed for chloride (or bromide, if requested) and the result reported as the acid. Make sure that the glass fiber filter plug is firmly in contact with the silica gel before and after sampling. Report the presence of chloride (or bromide) salts to the analytical laboratory.
Special requirements
 

 

* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Wipe Method
Wipe Method
Sampler/Sampling media
 

Wipe with Whatman smear tab. [WHA1450993]
Bulk Method
Bulk Method
 

 
On-Site Screening Techniques
On-Site Screening Techniques
Device Detector tube Detector tube CMS Chip CMS Chip
Model/Type Gastec 14L Matheson-Kitagawa 8014-173SB Hydrochloric acid, 1-25 ppm range Hydrochloric acid, 20-500 ppm range
Sampling information
(see manufacturer instructions) 		0.5-5 strokes, 0.05-76 ppm range, uncertainty 16.4% for 1-5 ppm, 8.2% for 5-20 ppm follow mfr instructions, 0.4-40 ppm range FES0000887
Exposure Limits
Exposure Limits
OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
NIOSH REL
Up to 10-hour TWA
(ST) STEL
(C) Ceiling
ACGIH TLV©
8-hour TWA
(ST) STEL
(C) Ceiling
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
PEL-TWA
 

 

 REL-TWA
 

 

 TLV-TWA
 

 

 PEL-TWA
 

0.3 ppm (0.45 mg/m³)
PEL-STEL
 

 

 REL-STEL
 

 

 TLV-STEL
 

 

 PEL-STEL
 

 
PEL-C
 

5 ppm (7 mg/m³)

 REL-C
 

5 ppm (7 mg/m³)

 TLV-C
 

2 ppm [2000]

 PEL-C
 

2 ppm
Skin notation
 

N

 Skin notation
 

N

 Skin notation
 

N

 Skin notation
 

N
Notes:
 

See 29 CFR 1910.1000 Table Z-1.

 Notes:
 

 

 Notes:
 

 

 Notes:
 

 
Health factors:  See NIH-NLM PubChem. IDLH
 

50 ppm
Carcinogenic classifications: IARC-3, TLV-A4 Notes:
 

 
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
 

3 ppm/20 ppm/150 ppm
Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Hydrogen chloride, anhydrous

NIOSH: Pocket Guide to Chemical Hazards - Hydrogen Chloride

Literature References

 
  • NOAA: CAMEO Chemicals - "Hydrochloric acid.
  • EPA: Hazard Summary - Hydrogen Chloride.
  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Hydrogen Chloride. See annual publication for most recent information.
  • Albert, R.E., A.R. Sellakumar, S. Laskin, M. Kuschner, N. Nelson and C.A. Snyder. 1982. Gaseous formaldehyde and hydrogen chloride induction of nasal cancer in rats. J. Natl. Cancer Inst. 68(4): 597-603.
  • Brooks, S M; M A Weiss; I L Bernstein, Reactive airways dysfunction syndrome (RADS). Persistent asthma syndrome after high level irritant exposures CHEST.;88(3):376-384 1985.
  • EPA: Integrated Risk Information System - Hydrochloric Acid. 1985.
  • Gorguner, M., Aslan, S., Inandi, T. and Cakir, Z.: Reactive airways dysfunction syndrome in housewives due to a bleach-hydrochloric acid mixture. Inhal. Toxicol. 16(2): 87-91, 2004.
  • IARC: Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Mists from Strong Inorganic Acids. 2011.
  • Micric, M. and Plavec, D.: Risk of acute bronchospasm and bronchial hyperreactivity from inhaled acid aerosol in healthy subjects: randomized, double-blind controlled trial. Croat. Med. J. 45(6): 709-714, 2004.
  • NIOSH: Occupational Health Guideline for Hydrogen Chloride. September 1978.
  • Serrano, M. et al.: Airway-centered interstitial fibrosis related to exposure to fumes from cleaning products. Arch Bronconeumol. 42(10): 557-559, 2006.
  • Sellakumar, A.R., C.A. Snyder, J.J. Solomon and R.E. Albert. 1985. Carcinogenicity for formaldehyde and hydrogen chloride in rats. Toxicol. Appl. Pharmacol. 81: 401-406, 1985

Last Updated Date : 12/31/2020