TO 00-25-172 - Robins Air Force Base

TO 00-25-172
4.18 LIQUID OXYGEN SERVICING IN AIRCRAFT
SHELTERS/FTR.
The following applies when servicing LOX in a shelter/FTR:
a. A dedicated shelter/FTR may be used to fill converters
removed from aircraft parked elsewhere. Follow procedures
outlined in Paragraph 4.17. Do not perform
other operations in the same shelter/FTR.
b. To service the aircraft themselves in individual shelter/
FTR without converters being removed, stop other operations
until the LOX servicing is completed and the
LOX cart removed. Follow procedures outlined in
Paragraph 4.17.
c. LOX cart servicing of an aircraft is not allowed during
the fuel servicing portion of a CSO.
d. No electrical switches will be operated.
e. No other operations or maintenance will take place in
the shelter/FTR.
f. The aircraft will be safed for CSO/maintenance.
g. No floor drains, traps, or other below floor areas will
be within 20 feet of the LOX servicing operation. If
drain channel is clean, underfloor weapons storage
vault is exempt. MAJCOM may exempt F-15 first generation
shelter guide rails as long as the rail channels
are free of all hydrocarbons and rails are placed down
in stowed position during LOX servicing (except those
next to main landing gear).
h. All puddled or wet hydrocarbons are cleaned from
shelter floor.
i. No non-LOX personnel or ignition sources are allowed
within 20 feet of LOX servicing operation. Cellular
phones and hand-held radios or any transmitting devices
will not be used and will be turned off within 50
feet of the servicing area.
j. LOX cart will not be stored in shelter/FTR. LOX cart
should be stored outside shelter/FTR in a separate
splinter-protected location.
k. Following LOX servicing, LOX cart is removed from
shelter then depressurized.
l. Clean, dedicated LOX drip pans or collection devices
will be used to catch LOX. Flat floor pans (when used)
should be at least 3 feet x2½feet x 3 inches.
m. Aircraft specific LOX servicing procedures are used.
n. Except for combat, the shelter doors will be positioned
as follows (minimum):
(1) Alert shelters will have at least one aircraft door
open.
(2) First generation HAS/PAS. The exhaust door and
one aircraft entry door will be fully open.
(3) Modified first generation HAS/PAS. The shelter
door will be open to the shelter centerline and
exhaust door will be fully open.
(4) Second/Third generation HAS/PAS. One aircraft
entry door may be fully opened or each aircraft
entry door may be opened 10 feet (20 feet total).
One exhaust door will be fully open.
4.19 NITROGEN SERVICING.
Nitrogen is used in pressure-operated equipment to expel
other gases from their cylinders and for purging tubes and
lines. Quality control procedures are outlined in TO 42B7-3-
1-1.
a. Gaseous nitrogen (N 2 ) is a colorless, odorless, tasteless
gas, slightly lighter than air. It is inert and does not
react with other substances nor will it support combustion.
b. Liquid nitrogen (LIN) is a colorless, odorless liquid,
which exists in the liquid state only at extremely low
temperature (-196 °C or -320.8 °F).
c. The following general guidance applies to both gaseous
and liquid nitrogen servicing. Specific information
covering gaseous nitrogen servicing is addressed
in Paragraph 4.20 and liquid nitrogen servicing in
Paragraph 4.21. It is not necessary to ground or bond
nitrogen servicing carts.
(1) Those persons not directly involved in nitrogen
servicing operations should stay outside a 20-foot
radius of the servicing point. Servicing personnel
shall wear PPE required for either gaseous or liquid
nitrogen servicing. Although nitrogen is an
inert gas, it is advisable that servicing personnel
keep their hands, feet, clothing, etc., clean and
free of petroleum base products.
4-18