1 Research performed by several Member Governments
has demonstrated that the seams and closures of immersion suits and
anti-exposure suits experience deterioration over time. The rate and
severity of deterioration may vary widely, depending upon the specific
components and procedures employed in the manufacture of the suit
and the conditions under which the suit is stored. However, even under
ideal conditions, the materials and adhesives used have a finite service
life and will inevitably experience a reduction in strength and/or
loss of watertightness with age.
2 The Guidelines for monthly shipboard inspection
of immersion suits and anti-exposure suits (MSC/Circ.1047) are very helpful in identifying obvious problems with a suit,
but do not adequately address deterioration of seams and closures
(zippers, etc.) which may not be readily apparent by visual inspection.
Such deterioration can be detected by pressurization of the suit with
air, and testing of the seams and closures for leaks with a soapy
water solution.
3 To ensure the maintenance of adequate strength
and watertightness of seams and closures of immersion suits and anti-exposure
suits with age, it is recommended that each suit be subjected to an
air pressure test such as the following, at intervals not exceeding
three years, or more frequently for suits over ten years of age:
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.1 A suitable head piece, fitted with a means
to inject air into the suit, should be inserted into the face orifice
of the suit and secured so as to minimize leakage around the face
seal. A low-pressure monitoring device, either integral to the fitting
for air injection or as a separate device, should also be inserted.
If the suit is fitted with detachable gloves and/or boots, the wrists
and/or cuffs should be sealed by inserting a short length of suitable
diameter plastic pipe and securing the gloves and/or boots with suitable
wire ties or hose clamps. The zipper should be fully zipped, and any
face flap closed. The suit should then be inflated to a pressure of
0.7 to 1.4 kPa (0.1 to 0.2 psi). If an auxiliary inflatable means
of buoyancy is provided, it should be inflated through the oral valve
to a pressure of 0.7 kPa (0.1 psi) or until firm to the touch.
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.2 Each seam and closure of the suit - and each
seam, oral tube and attachment points and joint or valve of any auxiliary
inflatable means of buoyancy - should then be covered with a soapy
water solution containing enough soap to produce bubbles (if leakage
is noted at a foot valve to the extent that air pressure cannot be
maintained, the valves should be sealed for the test).
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.3 If leaks are revealed by the propagation of
bubbles at seams or closures, the leaking areas should be marked and,
after cleaning the suit thoroughly with fresh water and drying it,
repaired in accordance with the suit manufacturer's recommendations.
4 It is recommended that the air pressure test
be performed at a suitable shore-based facility equipped to make any
necessary repairs in accordance with the manufacturer's recommendations.
In view of the wide variety of materials and adhesives used in immersion
suits and anti-exposure suits, it is strongly recommended that any
repairs to a suit be carried out by a facility which has access to
the original manufacturer's recommended servicing instructions, parts
and adhesives, and suitably trained personnel. The air pressure test
may be carried out on board ship if suitable equipment is available.