MIL-HDBK-1022A
10.3.2.14 Coatings. The CNG equipment comes factory-painted.
Specify special coatings where climatic conditions warrant.
Select a color from the base color scheme. Light beige is a
practical choice. White is a poor choice since the heat of
operation discolors it. Storage containers may have to be
painted white with blue letters to meet codes.
10.3.2.15 Water Content. Water content in natural gas varies
with region. Gas in the Southeast United States is usually
dry, while gas from West Virginia is very wet. Provide dryers
to dry the gas to a pressure (storage pressure) dew point
(PDP) at least 10 degrees F (6 degrees C) below the winter
design dry bulb temperature.
10.3.2.16 Design Standards. Design CNG systems to NFPA 52.
Use NFPA 54 for the gas supply to the compressor. Use the
ASME Code for Unfired Pressure Vessels for cascade storage.
Electrical work must conform to NFPA 70. Where collocating
CNG and gasoline stations, also use NFPA 30A.
10.3.3
Warning. During peak demand periods, some suppliers
mix propane air mixtures with natural gas. When the amount
added exceeds 10 percent by volume, the CNG produced from this
gas will normally not perform properly in CNG vehicles because
propane becomes a permanent liquid in storage tanks. Oxygen
sensors can be installed to shut down the station during such
periods. Installations with this situation should use dual
fuel vehicles.
10.4
HYDRAZINE STORAGE AND SERVICING FACILITIES
10.4.1
Uses. A blend of 70 percent hydrazine and 30
percent water, known as H-70 fuel, is used to operate the F-16
emergency power unit (EPU). The F-16 H-70 tank carries 56
pounds (25 kg) of fuel and requires servicing after the fuel
has been used. The H-70 tanks are removed from the aircraft
when the fuel is depleted below a level specified by the using
activity. The tanks are delivered to the servicing facility
where any remaining fuel is drained into a closed 55-gallon
(210 L) stainless steel drum. The aircraft H-70 tank is
filled using a closed system charging unit and is either
returned to the aircraft or placed in a handling/storage
container for future use. The bulk H-70 storage tank is a 55-
gallon (210 L) stainless steel drum containing approximately
51 gallons (190 L) of H-70. Nitrogen gas is used as an inert
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