A safety device for avoiding entrapment at a water reservoir drain by using a vacuum operated switch to interrupt power to the reservoir pump and by using a pressure pump to generate a positive pressure to dislodge {HEAD ~ the obstruction} from {TAIL ~ the drain} should a blockage occur 
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A safety device for avoiding entrapment at a water reservoir drain by using a vacuum operated switch to interrupt power to the reservoir pump and by using a pressure pump to generate a positive pressure to dislodge { HEAD ~ the obstruction } from { TAIL ~ the drain } should a blockage occur
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