Where is a labs fire extinguisher located?

Laboratory fire extinguishers shoud be located just inside each exterior door. To be as safe as possible they should probably be of the type AR-AFFF, that is Alcohol Resistant Aqueous Film Forming Foam. While these foam extinguishers are messy they extinguish the fire AND THEN they provide reflash protection. Other extinguishing agents will extinguish the fire but if all the elements of a fire are still there, oxygen fuel and temperature, then the fire can reignite. AR-AFFF prevents that and prevents the foam from degrading due to solvents which tend to be present in Laboratories.