**Water Lift**
- Relative to vacuum cleaners, water lift is a
measurement of the strength of the vacuum
produced by the suction motor. Suction gauges
used on vacuum cleaners are calibrated in "Inches
of Water Lift". This is equivalent to taking a
vertical tube, placing the bottom in a container
of water, attaching the vacuum cleaner hose at
the top and measuring how high above the water
surface the water in the tube rises. By the way,
one cubic inch of water weighs 0.036 pounds so
the negative pressure in pounds per square inch
can be found by multiplying the water lift by
0.036. If you see suction rated in
millibars
(mbar), multiply that number by 0.4 to convert it to
inches of water lift.