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August 04, 2025

According to Decree 280-2024 published on February 28, 2024, in the Gazette officielle du Québec, the amendment to the Appendix 1 of the Regulation respecting occupational health and safety (RSST, RLRQ, c. S-2.1, r. 13) will come into force on March 14, 2024. These regulatory changes have not yet been incorporated into the current Substance Data Sheets of the Sampling Guide for Air Contaminants in the Workplace. An update is currently underway and will be available as soon as possible. Consequently, the information contained in the data sheets of substances modified or added in Decree 280-2024 is partially inaccurate or incomplete. Please consult our infoLABO (in French only) for more details. Please contact our client service: [email protected] for further information.

Chlorine  

French name in the regulation: Chlore
CAS : 7782-50-5

Exposure Standards in RROHS regulation

Permissible exposure values (PEV)
ppm mg/m3 f/cc Notes
TWAEV - - - -
STEV - - - -
Ceiling 0,5 1,5* - -
Carcinogenicity Sensitizer
Simple asphyxiantPercutaneous
Prohibited useProhibited recirculation
Minimum exposureExplosion hazard
Ototoxic

TWA adjustment for unusual work schedules

1C : No adjustment

CNESST – Toxicological Index Service

Consult REPTOX file: Chlorine

Analysis:

Chlorine

Recommended method by the IRSST:
Method: MANUEL - ILD

Sampling protocol

Sampling device:
Parameters:
Flow rate: -
TWA sampling volume: -
STEL sampling volume: -
Remarks: Quantification of chlorine is done in the field with a direct-reading instrument (DRI). Refer to the user's guide accompanying the instrument.

Principle: Direct reading instrument-Electrochemical cell (DRI-elec)

Direct Reading Instrument (DRI). Consult the manufacturer's manual.
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.
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