Horse-Power 6 : The mechanical engineering unit of power, equivalent to working at the rate of 745. 7 watts (33 000 ft lbf/min. or 42. 4 B. t. u. /min. . See also: INDICATED HORSEPOWER and Rated Horsepower
H. J. Porter (Chairman - Technical Committee), Dictionary of Fire Technology, The Institution of Fire Engineers, The Victory Press (Leicester) Ltd. 1979 UK. (Fr Tech - Brit) {81}