On Thursday, February 5, in the College of Computing, a Teaching Assistant poured some excess nitric acid into a solvent waste bottle, producing a potentially dangerous and explosive mixture. The mixture lived up to its potential. Luckily, the reaction takes some time to occur and the lab was empty when the explosion took place – anyone in the lab at the time would very likely been seriously injured – glass shards and other debris were hurled at least 34 feet from the fume hood. As it was there were several thousand dollars of damage.

While the exact details are still under investigation, the incident points to the potential dangers of mixing waste streams. Too often, we receive waste which, from the content listing or waste characteristics, it appears that ALL waste is being dumped into a common container. If potentially incompatible components need to be mixed as part of a scheduled experiment or approved research protocol – that can be dealt with. For anything else, keep your waste streams as pure as possible (that includes mixing acids and bases under the assumption they will neutralize each other).

If you really believe you need to combine waste streams for space or other considerations – please consult with EHS beforehand.