Выражение встречается в следующем контексте:
If the plug is damaged, pay attention to the following: Plugs and sockets confirming to BS 4243 or BS 196 should be used wherever practicable. Domestic pattern plugs to BS 546 should not be used. The wiring of the plug should leave more slack in the earth continuity conductor than in the other cores, so that it is not the first core to be pulled out of its terminal should the cord grip fail. Plugs which have good grips capable of maintaining a firm hold on the cable sheath should be selected. In general, additional means should be provided to relieve stress on cable terminations in the plug. For example, additional cable clamps should be fitted or a substantial chain could be used to tether the machine to a fixed point. Plugs and sockets situated near the work site or outdoors should be to class IP 55 of BS 5490 to provide adequate protection against ingress of water, etc. and cable entries require effective sealing. Rubber shrouds should be provided over cable glands. Drip-proof (class IP X2 of BS 5490) plugs and sockets to BS 4343 are suitable for use indoors where the plug is away from the water spray area where the appliance is in use.

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