The explosionproof switchgear combinations are intended for use in Zone 1 and Zone 2 explosive gas atmospheres and Zone 21 and Zone 22 explosive dust atmospheres according to IEC/EN 60079-0 and IEC/EN 60079-2. IEC/EN 60079-2 ‘Equipment protection by pressurization p’ covers explosionproof equipment for equipment protection levels (EPL) ‘Gb’ (Zone 1), ‘Gc’ (Zone 2), ‘Db’ (Zone 21), ‘Dc’ (Zone 22) with the levels of protection ‘pxb’ and ‘pzc’.