Key Instruction Points
The collapse of a shelf in a flammable storage cabinet lead to an explosion and fire in a lab at X causing the destruction of two labs and damage ranging from $200,000 to 300,000 in repairs. Spills due to the unstable shelf had occurred previously but no one had tried to repair or replace the defective shelf. In this instance,12 containers of hexane were being unpacked into a flammable storage cabinet when one of the shelves collapsed. The resulting three-alarm blaze took about 20 fire trucks and 84 firefighters from several area fire stations more than an hour to extinguish.
Flammable liquids ignite when there is enough fuel and oxygen in the air to support a flame, as well as an ignition source. Common ignition sources in labs are Bunsen burners and stirrers with brush-type motors. Plugged-in electrical equipment could also be an ignition source. In this case, the ignition source was never determined.
There were about 50 gallons of flammables in the lab which lead firefighters to switch from water to dry powder extinguisher, and finally to chemical foam, which eventually put out the blaze.
In a completely separate incident at another institution, a spill occurred when a shelf located in a flammable storage cabinet under a chemical hood, collapsed. A gallon bottle of glycerol and a gallon bottle of isopropyl alcohol broke and spilled. Additionally, a gallon bottle of acetone had fallen off the shelf and was leaking. Rather than vacating the room and contacting the safety office to clean-up the spill lab personnel cleaned up the spill themselves which took about 30 minutes. The personnel recently attended training where emergency procedures were reviewed. They used a broom, a dustpan, and brush to pick up the broken glass and the liquid. They placed the entire contents of the spill, including the liquid, in a box designed for broken glass on the floor of the lab where it continued to evaporate over the weekend.
It is believed that improperly installed shelving clips caused the shelf to collapse. This was a new lab and the solvent cabinet was being used for the first time. An inspection of all the shelves in the area found other clips that were also not installed properly.
The personnel involved in incident did not follow the institution’s emergency procedures which had been reviewed during training and which are listed in a emergency flip chart which is posted in the lab. Lab personnel are responsible for cleaning up minor chemical spills, only. A minor chemical spill is defined as = 1 liter of any chemical that is NOT a carcinogen, acutely toxic or a reproductive hazard. The safety office and other emergency response personnel handle all other chemical spills.
Everybody should have left the room and someone should have called for help from a location where the safety office could call back to get information about the spill.
Besides posing a fire hazard (vapors from flammable liquids catch on fire, not the liquids themselves), they violated their institutions policies as well as EPA regulations regarding hazardous waste. It is against federal environmental regulations to evaporate chemical waste into the atmosphere.