Rope team may be used in the event of a crevasse accident, e.g. to make a Swiss pulley in order to rescue a fallen climber. For larger groups of about four people or more, recovering a fallen man is most easily done using a team pull. When "walking on a rope", the fall of one person - for example, into a crevasse - must be broken by the rest of the rope team members. So there is a danger that such a fall can endanger the entire team. On steep firn or ice-covered mountainsides, where possible and appropriate, the rope must be
Electro-pneumatic brake system on British railway trains thereby activating the disc brake. The "presence" of the voltage holds the brakes "off", providing a Fail Safe system. The 3 step "Westcode" brake uses three wires and these operate in a binary sequence to control the brake step. 10 & 11 are the brake coding to provide the 3 steps, 12 wire is emergency brake, 15 wire is EP brake negative. Positions on the brake handle are: This system remains in use today. On the previous EP brake systems, if the train divided or a serious air leak occurred the drop in Brake Pipe pressure automatically caused the brakes