IRSST - Institut de recherche Robert-Sauvé en santé et en sécurité du travail

Hydrogen chloride

French name in the regulation: Chlorure d'hydrogène
CAS : 7647-01-0
Synonyms: Hydrochloric acid

Exposure Standards in RROHS regulation

Permissible exposure values (PEV)
ppm mg/m3 f/cc Notes
TWAEV - - - -
STEV - - - -
Ceiling 2 3* - -
Simple asphyxiant Percutaneous
Minimum exposure Sensitizer
Prohibited use Prohibited recirculation

TWA adjustment for unusual work schedules

1A : No adjustment

CNESST – Toxicological Index Service

Consult REPTOX file: Hydrogen chloride


Chlorure d'hydrogène

Method: IRSST - 211
Sampling device:
Sampling media required:
974 Impregnated quartz filter in series with quartz filter, 37 mm, 3-part

Flow rate: 2 L/min
TWA sampling volume: -
STEL sampling volume: 30 L
Remarks: The cassette consists of a 37 mm quartz fibers prefilter that will collect the acids in particulate form, followed by a Na2CO3 impregnated quartz fiber filter that will adsorb the acids in vapour form, the two filters separated by an inert spacer. Stable for 7 days at 25°C and 28 days at 4°C. The recommended method needs a minimum of 3 field blanks.
Principle: Ion chromatography with conductivity detection (IC-CD)
Precision (%): 5,1
Minimum reported value: 8 µg
Remarks: All the chloride ions not originating from the acid can cause a positive interference. Additionally, inorganic acids can react with co-sampled particulate matter on the pre-filter. For example, zinc oxide leads to lower results for hydrogen chloride. Three ions can be determined simultaneously: bromide, chloride and nitrate. Analytical results are expressed as hydrochloric acid.
IRSST. "Analyse des acides inorganiques volatiles". Méthode 211. Publiée.
Following the amendment of Appendix 1 of the Quebec Regulation respecting occupational health and safety (RSST, RLRQ, c. S-2.1, r. 13), part of Quebec Occupational Health and Safety Act, which came into effect on March 26, 2020, the TWAEV, STEL and Ceiling values for certain substances are now expressed in ppm. For these substances, the IRSST performed the conversion calculations to express these TWAEV, TWA and Ceiling values in mg/m3, which thus appears in its Sampling Guide for Air Contaminants in the Workplace (Guide d'échantillonnage des contaminants de l'air en milieu de travail ) and the associated Substance Data Sheets. However, it is imperative to refer to the values expressed in the RSST which are legally binding.