What happened?

A researcher was sterilizing tissue culture plates using one gallon of 200 proof ethanol inside an autoclave tray and a Bunsen burner, which was intended to create a “sterile field,” for the plates to air-dry. While transferring one of the plates, the Bunsen burner ignited the ethanol vapors. The plate fell into and ignited the tray of ethanol creating a flame eight to twelve inches high. The researcher attempted to put the fire out with a fire extinguisher, but instead inadvertently spread the fire out of the tray, igniting a nearby cardboard box and setting off the fire sprinklers. The researcher moved the box and the tray into the direct spray of the sprinkler, which extinguished the fire. Fortunately, the researcher had only minor burns on their hand. However, sprinkler water flooded the lab and several floors below.

What was the cause of the incident?

The immediate cause of the incident was the improper use of a flammable liquid in the presence of an open flame. There were numerous underlying causes, including:

• Inadequate risk assessment: the lab did not have a structured process for identifying, assessing and communicating about the potential risks associated with new tasks and modified procedures; therefore, the risks associated with handling a large quantity of flammable ethanol near an open flame were not mitigated.
• Inadequate lab housekeeping: a combustible cardboard box was present near an open flame.
• Incorrect use of a fire extinguisher: the fire extinguisher spread the fire instead of extinguishing it.

What went right?

• Building occupants knew the location of the emergency assembly point (EAPs) and assembled there upon building evacuation.
• The PI and lab staff were proactive with corrective actions, appointing additional safety contacts and requesting training.

What should have been done differently?

• Establish a consistent process and expectation in the lab for how new and modified procedures are assessed for risk.
• Notify and collaborate with PIs on new and modified procedures.
• When the fire alarm and sprinklers activated, lab staff should have evacuated immediately and made emergency notifications.