Synonyms: Aqua fortis; Spirit of niter; White fuming nitric acid (WFNA); Red fuming nitric acid (RFNA); Hydrogen nitrate

OSHA IMIS Code Number: 1860

Chemical Abstracts Service (CAS) Registry Number: 7697-37-2

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: QU5775000

Department of Transportation Regulation Number (49 CFR 172.101) and 2012 Emergency Response Guidebook [4 MB PDF, 392 pages]: 2031 157 (other than red fuming); 2032 157 (fuming and red fuming)

NIOSH Pocket Guide to Chemical Hazards - Nitric Acid: Physical description, chemical properties, potentially hazardous incompatibilities, and more

National Toxicology Program (NTP) carcinogenic classification: Not listed

International Agency for Research on Cancer (IARC): Not listed

U.S. Environmental Protection Agency (EPA) carcinogenic classification: Not listed

EPA Inhalation Reference Concentration (RfC): Not established

Agency for Toxic Substances and Disease Registry (ATSDR) Inhalation Minimal Risk Level (MRL): Not established

NIOSH Immediately Dangerous to Life or Health (IDLH) concentration: 25 ppm

Notes on Other Potential Health Effects and Hazards

1. Nitric acid is not combustible but enhances combustion of other substances (NIOSH/IPCS 2006).
2. One death from occupational inhalation of nitric acid was reported to a U.S. poison control center in 2001 (Litovitz et al. 2002).
3. Another death from occupational inhalation of nitric acid recently occurred when a patient was asymptomatic from exposure to the chemical until more than 50 hours later. He then developed pulmonary edema and acute respiratory distress syndrome before going into fatal circulatory collapse (Murphy et al. 2010).

Date last revised: 09/06/2012

Literature Basis

• ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) – Nitric Acid. 2001.
• Litovitz, T.L. et al.: 2001 Annual Report of the American Association of Poison Control Centers Toxic Exposure Surveillance System. Am. J. Emerg. Med. 20(5): 391-452, 2002.
• Murphy, CM, Akbarnia, H, and Rose, SR: Fatal pulmonary edema after acute occupational exposure to nitric acid. J Emerg Med. 39(1): 39-43, 2010.
• NIOSH: Occupational Health Guideline for Nitric Acid. September 1978.
• NIOSH: Criteria for a Recommended Standard - Occupational Exposure to Nitric Acid. March 1976.
• NIOSH/IPCS: International Chemical Safety Cards - Concentrated Nitric Acid. October 10, 2006.

Primary Laboratory Sampling/Analytical Method (SLC1):

• sampling media: Treated Silica Gel Tube (Supelco, ORBO-53; SKC, 226-10-03 or equivalent)
  maximum volume: 96 Liters
  maximum flow rate: 0.2 L/min (TWA)
  maximum volume: 7.5 Liters
  maximum flow rate: 0.5 L/min (STEL)
  current analytical method: Ion Chromatography; IC
  method reference: OSHA Analytical Methods (OSHA ID-165SG)
  method classification: Partially Validated
  note: Phosphoric, Nitric, Sulfuric, and Hydrobromic(HBr) Acids may be submitted on the same sample (TWA only). For STEL samples, submit as a separate sample. Make sure that glass fiber filter plug is firmly in contact with silica gel before sampling and before sealing tube for shipment. Interferences: Particulate acids, salts of an anion.

Secondary Laboratory Sampling/Analytical Method (SAM2):

• device: Detector Tube
  manufacturer: Dräger
  model/type: Nitric Acid 1/a, order no. 67 28311
  sampling information: 10 or 20 strokes
  upper measurement limit: 50 ppm
  detection limit: approx. 1 ppm
  overall uncertainty: 16%
  method reference: on-site air secondary (manufacturer)
  


• device: Detector Tube
  manufacturer: Gastec
  model/type: 15L
  sampling information: 0.5 or 10 strokes
  upper measurement limit: 40 ppm
  detection limit: 0.05 ppm
  overall uncertainty: 25% for 1 to 5 ppm, 16% for 5 to 20 ppm
  method reference: on-site air secondary (manufacturer)
  


• device: Detector Tube
  manufacturer: Gastec
  model/type: 80
  sampling information: 2 strokes
  upper measurement limit: 200 ppm
  detection limit: 2.5 ppm
  overall uncertainty: unknown
  method reference: on-site air secondary (manufacturer)
  


• device: Detector Tube
  manufacturer: Matheson-Kitagawa
  model/type: 8014-233S
  sampling information: follow manufacturer’s instructions
  upper measurement limit: 20 ppm
  detection limit: approx. 1 ppm
  overall uncertainty: unknown
  method reference: on-site air secondary (manufacturer)

Wipe Sampling Method:

• sampling media for liquid solutions: Whatman smear tab
  analytical solvent: Deionized Water