Access panels are manufactured to resemble the main ceiling panels both in respect to size and edge detail. They are used in locations where security tiles are employed or where regular access to the ceiling void is necessary for electrical or mechanical services or devices. The panels are manufactured with reinforced frames that provide rigidity to the panel whilst permitting the panel to hinge down for access to the ceiling plenum. Access panels are fitted with locking devices to retain the panel in the ceiling and prevent unauthorised access. Locks can be operated with a square shanked key (budget locks) or, in particularly sensitive areas such as police stations or prisons, the locks can be key operated (Yale Type). Where Yale type locks are specified and there are numerous access panels required in a ceiling the keys can be “suited” such that the same key operates all of the panels if that is desired.