Classes and offices were evacuated for about 40 minutes at 12 p.m. Thursday after a classroom experiment resulted in a small explosive chemical reaction contained within a venting hood in McLane Hall. No one was injured.

The reaction triggered fire alarms although there were no flames. Students, faculty and staff responded to the alarms by following the building evacuation plan and waiting in designated areas away from the building while Fresno Fire Department personnel investigated.

The safety and alert systems worked as designed, one investigator said as evacuation was lifted and the classroom and office building was re-occupied.