Fume Ventilation (KV 156)


What Happened?

At 3:30 p.m. on February 7, 2017, an employee was participating in a meeting in a conference room that was adjacent to the facility laboratory where xylene was being used. During the meeting, the laboratory ventilation hood fan failed and xylene was released into the laboratory and migrated into surrounding areas. The employee, who had documented chemical sensitivity, displayed symptoms of overexposure.

While emergency services were contacted, the employee was administered an EpiPen and was removed from the affected area. The employee was transported to a nearby hospital, where they were treated for hypoxemic respiratory failure and held overnight. The incident investigation reported that the laboratory had been conducting an 8-hour test where xylene was being boiled despite the exhaust fan in the laboratory hood failing. 

Contributing Factors

How many times have they worked with the fan in operation and no one had a reaction to the chemicals?  Likelihood vs consequence needed to be considered concerning someone not being able to tolerate the chemicals in the air.

What Can We Learn?


Using a Questioning Attitude when the exhaust fan malfunctioned would have made the team stop work and would have prevented the xylene from boiling and the fumes from continuing to spread.

Procedures should have been in place requiring the fan to be in operation during any work that released chemicals in the air. 


Overconfidence was at fault in this situation. The xylene was allowed to be boiled even though the workers were aware that the exhaust fan was broke.

Ask the Right Questions

How does this relate to our work?

Where do we have similar traps?

What Tools can we use to avoid a similar incident?

Was a stop work point missed?