INTERSPIRO DIVATOR DP1 User Manual page 13

DP1
WARNING
If the supply hose is connected to the diver and dived without
being pressurized the water pressure may become higher than
the air pressure on the inside of the hose and may partially fill
the inside of the hose with water. If the surface attendant then
realizes his fault and pressurizes the hose, water could be
supplied to the diver instead of air.
WARNING
If the supply hose ever enters the water not pressurized there
is the possibility of water entering the hose.
WARNING
A pressurized supply hose is not to be connected to a diver
under water.
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