6　Piping Layout for Special Services

6.1　Piping Layout for Liquefied Hydrocarbon Service

6.1.1　The piping for liquefied hydrocarbon service shall be routed above ground.

Where the piping is routed in pipe trenches，provisions shall be made to prevent accumulation of liquefied hydrocarbons in pipe trenches，and seal partitions shall be provided at locations where piping is routed to/from process plants and building.

6.1.2　Safety provisions shall be made for the piping containing liquefied hydrocarbons to avoid possible pressure rise due to environmental influence when the piping may be closed at both ends.

6.1.3　Heat compensation for the piping containing liquefied hydrocarbons shall be of natural compensation.