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

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.

Carbon dioxide

French name in the regulation: Carbone, dioxyde de
CAS : 124-38-9
Synonyms: Dioxyde de carbone

Exposure Standards in RROHS regulation

Permissible exposure values (PEV)
ppm mg/m3 f/cc Notes
TWAEV 5000 9000 - -
STEV 30000 54000 - -
Ceiling - - - -
Simple asphyxiant Percutaneous
Minimum exposure Sensitizer
Prohibited use Prohibited recirculation

TWA adjustment for unusual work schedules

1C : No adjustment

CNESST – Toxicological Index Service

Consult REPTOX file: Carbon dioxide


Carbone, dioxyde de

Method: IRSST - 34-C
Sampling device:
Flow rate: -
TWA sampling volume: -
STEL sampling volume: -
Remarks: Refer to the user's guide accompanying the instrument.
Principle: Direct reading instrument-Infrared detection (DRI-IR)
Remarks: Carbon dioxide is quantified in the field with a direct-reading instrument (DRI). The minimum reported value is 18 mg/m³ (10 ppm). The reference method corresponds to calibration of the DRI.
IRSST. "Étalonnage d'un instrument à lecture directe du dioxyde de carbone dans l'air". Méthode 34-C. Méthodes d'étalonnage. Montréal: IRSST, 1998.
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.