Safety is a vital factor in the operation of equipment within aircraft which could be travelling at typical altitudes of 6 miles. Particularly important is the need to prevent possible electrical fires, the use of fire-retardant materials, and the need for equipment to operate safely at high altitudes. A major area for problems in the aircraft is corrosion due to moisture emanating from the galley. Spillages in particular can be a problem, as this affects the main cabin floor. Immediately below this floor are the cables which run from the cockpit to the rudders, and hence control the aircraft. Each subsection of a galley has predetermined and carefully marked maximum load capacity and these will be considered when the airlines brief suppliers on their requirements.