PADI defines technical diving as "diving other than conventional commercial or recreational diving that takes divers beyond recreational diving limits (130 feet (40 m)). It is further defined as an activity that includes one or more of the following: diving beyond 40 meters/130 feet, required stage decompression, diving in an overhead environment beyond 130 linear feet from the surface, accelerated stage decompression and/or the use of multiple gas mixtures in a single dive.