Nitric Acid
Overview
CAS No. 7697-37-2
Nitric acid (HNO₃) is a colorless liquid with yellow or red fumes with an acrid odor. Exposure to nitric acid can cause irritation to the eyes, skin, and mucous membrane; it can also cause delayed pulmonary edema, pneumonitis, bronchitis, and dental erosion. Nitric acid is highly corrosive. Workers may be harmed from exposure to nitric acid. The level of exposure depends upon the dose, duration, and work being done.
Nitric acid is used in many industries. It’s used in the manufacture of fertilizers, dyes, and explosives. Nitric acid is also used in the polymer industry. Some examples of workers at risk of being exposed to nitric acid include the following:
- Factory workers in plants that produce nitric acid
- Factory workers in plants that manufacture explosives
- Workers in facilities that use nitric acid
NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses nitric acid, please read chemical labels and the accompanying Safety Data Sheets for hazard information. Visit NIOSH’s page on Managing Chemical Safety in the Workplace to learn more about controlling chemical workplace exposures.
The following resources provide information about occupational exposure to nitric acid. Useful search terms for nitric acid include “aqua fortis,” “engravers acid,” “hydrogen nitrate,” “red fuming nitric acid,” “white fuming nitric acid.”
NIOSH Chemical Resources
NIOSH Resources
- NIOSHTIC-2 search results for nitric acid—NIOSHTIC-2 is a searchable database of worker safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.
- Immediately Dangerous to Life or Health (IDLH) Value Profile: Nitric Acid—NIOSH reviews relevant scientific data and researches methods for developing IDLH values.
- NIOSH Worker Health Study Summaries—NIOSH conducts research to prevent illnesses and injuries in the workplace. The NIOSH Worker Notification Program notifies workers and other stakeholders about the findings of these research studies.
Selected Publications
- Criteria for a Recommended Standard: Occupational Exposure to Nitric Acid—DHHS (NIOSH) No. 76-141. Presents a standard to prevent the adverse effects of exposure to nitric acid over a working lifetime.
- Occupational Safety and Health Guideline for Nitric Acid—DHHS (NIOSH) No. 81-123.
Related Resources
- EPA Chemistry Dashboard
- OSHA Hazard Communication
- OSHA Chemical Sampling Information: Nitric Acid
- OSHA Methods: Nitric Acid (Acid Mists)
- EPA Acute Exposure Guideline Levels (AEGLs): Nitric Acid
- NLM Hazardous Substance Data Bank: Nitric Acid
- NLM Haz-Map: Nitric Acid
- New Jersey Hazardous Substance Fact Sheets: Nitric Acid