POOL & SPA NEWS,
September, 1997
Tests Show Entrapment is Preventable
Covered, duel main drains,
pool pump speed of 6 fps
get safety nod in NSPF report
BY ANNE BAYE ERICKSEN
SAN ANTONIO
A report just released by the National Swimming Pool Foundation has
concluded that entrapment, evisceration and entanglement accidents can
be prevented if pools and spas incorporate three specific design
elements: a dual main drain, anti-vortex-plate or grate drain covers,
and a maximum pump suction velocity of 6 feet per second.
The report titled Dual Main Drain Suction Entrapment, Hair
Entrapment/Entanglement Test Report, is the result of more that 20 NSPF
sponsored tests conducted by authors William Rowley, Ph.D., PE, and Glen
H Egstrom, Ph.D., in Rowley's home pool in Palos Verdes, Calif., on
April 4 and May 23.
As part of the study, Rowley, chairman of the board at Rowley
International Inc. in Palos Verdes Estates, Calif., allowed himself to
be trapped against several covered and exposed drains in order to get
vacuum pressure readings.
Rowley and Egstrom a professor emeritus from the University of
California, Los Angeles, concluded that a pool or spa with all three
listed design considerations would offer bathers protections against all
three types of injury.
"This is the first time, to my knowledge, that simultaneous
tests have been done to identify safe conditions for all three
circumstances," said Rowley.
"Only if all three hazardous conditions are prevented does a
safe condition exist, and from our tests, we couldn't find any.