The American NEC has similar access requirements Nick:
110.26 Spaces About Electrical Equipment. Sufficient access and working space shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment.
It goes on to list the minimum depth of working space in front of equipment, based upon voltage and other considerations, the minimum being 3 ft. for a 120/240V service. It also specifies a minimum working width of 30 in. or the width of the equipment, whichever is greater, and says that equipment panels and doors must be capable of being opend to at least 90 degrees.
