Figure 4-3. Mercury Cleaning Apparatus
tube with solution of strong soap and ammonia, Federal
Next swab tube with a solution
of nitric acid, (25 percent acid and 75 percent distilled
Rinse cleaned tube with distilled
water and dry with ethyl alcohol, Federal Specification
O-E-760, Type II.
(3) Reservoir servicing. Fill reservoir when
required using the following procedures:
The fill mark is located on a plate,
or plates, near the bottom of the
manometer scale. Either a water
fill or a mercury fill plate or both
may be used. The presence of
either or both plates indicates the
materials of construction used for
parts that come in contact with
the indicating fluid and indicates
what fluids may safely be used in
the manometer. Improper fluid
may cause damage to manometer.
(a) Remove fill plug from well and
ensure drain plug is tight.
(b) Pour indicating fluid into the well
to bring level up to the fill mark designated by the fill
plate of the liquid being used.
Keep manometer reservoirs filled
to specified level (mercury or
water). When water is used, add a
small amount of aniline dye, MIL-
A-10450 (usually red), to facilitate
quick and accurate readings.
(4) Operating procedures. With suitable
connections made and the manometer adjusted, apply
pressure (or vacuum) to the manometer and the
instrument being tested. Gradually apply the pressure
covering the entire instrument range and record
comparative readings. Refer to TM 55-6685-201-12.
(5) Safety practices. All of the cleaning
agents except water are toxic and should be used with
All except water and carbon
flammable. Use in well-ventilated
area, avoid inhalation of fumes
and skin contact. When mixing
acid and water together, always
pour the acid into the water.
Never pour water into acid. Avoid
skin contact with the acid and
with the mixture. Avoid skin
contact with the alcohol used for
a rinse. Do not drink the alcohol:
acute illness and death may
(6) Mercury spill procedures. Do the
following whenever mercury is spilled:
(a) Deactivate equipment, give the
alarm, and activate exhaust systems which exhaust
room air to the outside.
systems. Close vents and doors that would allow
mercury fumes and vapors to enter other work areas.
(c) Leave the area and take action to
assure that personnel are kept out of the contaminated
Change 3 4-4