the bulkheads, you must tighten the packing before
designated for air testing are provided with fittings for
attaching the air test set. In the case of tanks, you may
conducting the air test to maintain the air pressure.
use sounding tubes or air escapes to connect the air test
M a ke s u r e t h a t t h e c r ew i s awa r e o f t h e
set. Figure 3-19 shows the air test set that is provided
compartment air test being conducted. Post signs at
for shipboard use. The manufacturer's technical
every possible access to the compartment(s) being
manual, provided with each set, gives detailed
tested. If an observer is stationed inside the
instructions for operating the air test set.
compartment during the compartment air test, each
access to the compartment must have someone posted
at the access closure. The guards are to prevent the
access closure from being opened until the excessive
pressure within the compartment is relieved. The air
STORAGE BOX
test pressure used in a compartment air test is relatively
low. However, a dangerous total force can be
AIR TEST SET
INSTRUCTION
MANUAL
d eve l o p e d o n q u i c k - a c t i n g d o o r s a n d h a t c h e s .
CHARGE LINE
Personnel should be instructed not to attempt to open
EXTENSION
HOSE
quick-acting doors or hatches when a compartment is
under air test. A person opening these doors or hatches
while the compartment is under pressure could likely
SENSING LINE PROBE
sustain severe injuries.
EXTENSION LEGS
SENSING LINE
EXTENSION
PIPE TO HOSE ADAPTERS
When conducting a compartment air test on a large
DCf0317
compartment, use as many personnel as required to
check for leaks. The personnel involved with the test
need to maintain communication with each other. The
X40J (salt and pepper or international orange) rig can
Figure 3-19. Air test set.
be used, allowing you to have an isolated circuit
without interruptions. When you are conducting a
The information contained in the ship's schedule
compartment air test, any loss of pressure in excess of
of watertight integrity tests and inspections must be
the allowable drop listed in the schedule over the
strictly adhered to when conducting compartment air
specified period of time indicates deterioration of the
tests. The air test pressure listed in the schedule must
watertight integrity of the compartment. If corrective
NEVER be exceeded. You can seriously damage the
measures are beyond the capacity of ship's force, the
structures and boundaries of the compartment being
compartment must be listed as UNSATISFACTORY.
tested if the recommended pressure is exceeded.
You must then request that repairs be completed during
the next availability.
Before starting an air test, you need to conduct a
visual inspection of the compartment and repair all the
While the compartment is under test, leaks will be
leaks that you find. Notify the engineer officer, the
disclosed by hissing or whistling noises as the air
DCA, and the OOD of your intent to conduct a
escapes. All leaks should be located, marked, and
compartment air test and which compartments will be
listed for corrective action. You should repair all leaks
involved. Also, have an Electrician's Mate (EM) assist
that were found and then test the compartment again. If
in de-energizing the electrical push-button alarms and
the allowable pressure drop is again exceeded on this
remote-controlled valves for sprinkling, flooding, or
test, apply a soap solution to the boundaries of the
counterflooding systems if any are installed in the
compartment and to all joints, fittings, and closures.
compartment to be tested. These devices have
When the air pressure is applied, bubbles will be
diaphragm covers and would be activated when the air
formed by escaping air, thus indicating the location of
test pressure is admitted to the compartment unless
the leaks.
they had been previously de-energized.
The observer inside the compartment will have a
All fittings that serve the compartment must be
lighted candle. As the observer goes over areas where
secured or blanked off before the air test is conducted.
leaks are suspected, the deflection of the flame will
If any rotating shafts or other moving parts penetrate
indicate the location of leaks.
3-23
