Safety cabinets for flammable liquids must be inspected regularly by a qualified person. The inspection focuses in particular on the locking devices for doors and connections, the seals and the air exchange.
It is advisable to carry out inspections at least once a year.
See DIN EN 14470-1 “Feuerwiderstandsfähige Lagerschränke – Teil 1: Sicherheitsschränke für brennbare Flüssigkeiten“.
Great mechanical stress (increase in the permissible load or superstructure) has a negative effect on the flame resistance of a safety cabinet.