(4) Preventive Maintenance Checks and Services is performed every six
months by a medical equipment repairer.
(5) All repairs, except user items, are to be performed during PMCS or on
an as-needed basis.
b. General Maintenance Information. If everyone does his part to maintain the
equipment, the common problems causing equipment malfunctions can be avoided.
Common problems. Following are the common problems:
(a) Filters not changed when necessary.
(b) Collection and overflow bottles allowed overfilling, allowing fluid to
enter system components.
If fluid enters the compressor assembly, you must replace the motor.
Split suction tubing.
(d) Bottle tops and jars not tightly sealed.
(2) Methods of measurement. The following are the methods of
(a) Pressure, including negative pressure (suction), is measured in
millimeters of mercury (mmHg) or centimeters of water (cmH2O).
(b) The Emerson high-volume suction apparatus measures suction in
cmH2O which is also the most common method of measurement.
(c) The measurement differential between mmHg and H2O is 13.6.
This means that one measurement mmHg equals 13.6 mm of H2O. Since one cm
equals ten mm, 1mmHg = 1.36cmH2O. One atmosphere (the normal pressure of air at
sea level) is 760mmHg or 1034cmH2O.
(3) Operating specifications. Ensure the vacuum level is 0 to 60cmH2O (0
to 44mmHg). Ensure the unit operates to the parameters specified in Table 1-1.