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

Nitric acid  

French name in the regulation: Acide nitrique
CAS : 7697-37-2

Exposure Standards in RROHS regulation

Permissible exposure values (PEV)
ppm mg/m3 f/cc Notes
TWAEV 2 5,2 - -
STEV 4 10 - -
Ceiling - - - -
Carcinogenicity Sensitizer
Simple asphyxiantPercutaneous
Prohibited useProhibited recirculation
Minimum exposureExplosion hazard
Ototoxic

TWA adjustment for unusual work schedules

II : Daily adjustment

CNESST – Toxicological Index Service

Consult REPTOX file: Nitric acid

Analysis:

Nitric acid

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

Parameters:
Flow rate: 2 L/min
TWA sampling volume: 240 L
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. The sampling cassette 974 is stable two months. The sample is 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 (%): 2,6
Minimum reported value: 8 µg
Remarks: All the nitrate 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. Three ions can be determined simultaneously: bromide, chloride and nitrate. Analytical results are expressed as nitric acid.
IRSST. "Analyse des acides inorganiques volatiles". Méthode 211. Publiée.