Nitric Acid Incident

A researcher was cleaning a piece of glassware with nitric acid/water. The researcher poured the waste nitric acid/water into a 250 ml brown glass container labeled as waste and sealed the bottle. The researcher did not know what the contents of the waste container were prior to adding the waste nitric acid/water. This container was placed near the front edge of the fume hood. This container developed pressure and exploded. A 1 L container of 70% nitric acid, a 250 ml container of 1-Hexene and another unknown brown glass chemical container were shattered by the exploding waste container. The flammable vapors found an ignition source and caught fire inside of the fume hood. The container of 1-Hexene was blown out of the fume hood, shattered and landed on the floor next to the piece of equipment and caused the cooler and other combustibles to burn. It is unknown how the 1-hexene started to burn. By the time the Fire Department arrived, the fuel sources for both fires were mostly used up and the fires had partially extinguished. It was later determined that the brown waste bottle possibly contained cyclohexane and sodium metal.

Lessons Learned:

  1. Never add any water to an unmarked container.
  2. Label everything with the common chemical name.
  3. Always attach your waste label before you add the waste and fill it out completely and accurately. It is important to follow the directions on the back side of the chemical waste label. Chemical Waste Labels are provided by DEHS free of charge.
  4. Do not use glass to store chemical waste.

If you have any questions please contact the Chemical Hygiene Officer at or call 302-831-8475.