Page 52 - kursus eBook

DRAFT GUIDELINE ON DOMESTIC GAS PIPING SYSTEM

The storage and piping system must also be protected against possible damages from
encroaching vehicles by installation of barriers or walls whenever required.

Accessibility

Storage facilities need to be located where there is adequate provision of access and exit
routes for gas delivery tankers and also emergency equipment. Escape routes must also be
provided for operating personnel during emergencies.

Ventilation

Storage facilities must have good natural ventilation to ensure safe dilution of leaking gas.

A typical layout plan of a LPG bulk storage facility with safety distance, security,and damage
protection and good accessibility for refilling is as shown below.

Bollard pole for
vehicle damage
protection x x x
x x
LPG T AN K TANKER ACCESS ROAD
LPG T AN K
2m x x
H IGH
FEN C E
x x x
D E FLEC TION W ALL

Corrosion protection

Every buried container and pipeline shall be protected against corrosion by protective
coating or wrapping of enamels or plastic materials supplemented by an adequately
designed cathodic protection system.

Cathodic protection is an electrical technique for imposing a potential on the protected
container or pipeline to counter the tendency for electrochemical ion migration and stop
corrosion almost completely. The cathodic protection system may be of the sacrificial anode
or impressed current type but in either case shall be provided with a point at which a test
can be made to determine the efficacy of the system.

Backfilling

Backfilling material immediately adjacent to underground/mounded container shall consist of
at least 150 mm of non-corrosive inert material such as water-washed sand free from soil,
rocks, gravel or ashes and other deleterious matter. Backfilling sand shall have a minimum
resistivity of 100 Ω when tested after thorough moistening with distilled water. The sand
shall be well tamped into place during the backfilling operation. Mounded containers shall
have the upper surface covered with earth to a depth of at least 600 mm.

Electrical and electrostatic hazard precaution

According to MS 830, an area classified as "hazardous" is an area in which any flammable
atmosphere is continuously present (Zone 0), or is likely to occur in normal operating

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