Focus on Nitric Acid-Environmental Health & Safety - Carnegie Mellon University

Wednesday, April 1, 2015

Focus on Nitric Acid

Nitric acid is one of the most common chemicals present in our laboratories, for its qualities of being both a strong acid and a strong oxidizer.  These very properties make it prone to a number of common accidents and injuries.

Nitric is the culprit in what is, without question, our most common lab emergency issue:  hazardous waste containers or other experimental vessels that have exploded from interaction between nitric acid an organic such as ethanol or methanol.  The aftermath is very serious, not only from the spray of strong acid, but also the power of the incident, which has blown doors off of cabinets and trashed fume hoods.  The photo here is of just one incident.

Couple this with the fact that a common lab mixture is called “Nital,” which is a mixture of nitric acid and ethanol or methanol, and is commonly used in etching.  If you use nitric acid, please go to this link and read the Fact Sheet prepared for the use of Nital.  (There are some other great explosion photos in it!) http://www.cmu.edu/ehs/fact-sheets/Fact%20Sheet%20-%20Use%20of%20Nitric%20Acid%20%20Alcohol%20Solutions.pdf