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September 15, 2025

Ammonia

French name in the regulation: Ammoniac

CAS : 7664-41-7

Exposure Standards in RROHS regulation

Permissible exposure values (PEV)

	ppm	mg/m³	f/cc	Notes
TWAEV	25	17	-	-
STEV	35	24	-	-
Ceiling	-	-	-	-

Carcinogenicity		Sensitizer
Simple asphyxiant		Percutaneous
Prohibited use		Prohibited recirculation
Minimum exposure		Explosion hazard
Ototoxic

TWA adjustment for unusual work schedules

1B : No adjustment

CNESST – Toxicological Index Service

Consult REPTOX file: Ammonia

Analysis:

Ammoniac

Method: IRSST - 49

Sampling protocol

Sampling device:
Parameters:
Flow rate: -
TWA sampling volume: -
STEL sampling volume: -
Remarks: Refer to the user's guide accompanying the instrument.

Principle: Direct reading instrument-Electrochemical cell (DRI-elec)
Remarks: Ammonia is quantified in the field with a direct-reading instrument (DRI). The minimum reported value is 2.1 mg/m³ (3 ppm). The reference method corresponds to calibration of the DRI.

Reference

IRSST. "Méthode d'étalonnage d'un instrument à lecture directe". Méthode 49. Non publiée.

Ammoniac

Method: IRSST - 220-1

Sampling protocol

Sampling device:
Sampling media required:

#IRSST	Description
2144	Tube of carbon pretreated with sulfuric acid 500/250 mg

Parameters:
Flow rate: 0,10 - 0,5 L/min
TWA sampling volume: 24 L
STEL sampling volume: 7,5 L
Remarks: These tubes have a limited shelf life. It is important to respect the expiration date printed on the package.

Analytical protocol

Principle: Ion chromatography with conductivity detection (IC-CD)
Precision (%): 4,04
Minimum reported value: 9,4 µg
Remarks: The ammonium ion (NH4+) is being analyzed, so all ammonium salts and some substituted ammoniums will cause interference. The analytical results are expressed as ammonia (NH3).

Reference

IRSST. "Analyse de l'ammoniac dans l'air". Méthode 220-1. Non publiée.