Table 5.2.5　Minimum net horizontal distance between underground direct burial pipelines(m)

Table 5.2.5（continued）

Notes:1　The minimum distance in the table is calculated from the external edge of pipe wall，trench wall，protection facility or from the outmost cable.Nominal diameter is used forp ipeline.
2　In case that the distance between thermal piping（pip etrench）and electric cable conduit cannot comply with the distance specification in the table，thermal insulation measures may be taken to prevent overheating of cable.
3　In case that partial electric power cable is protected by conduit or partition plate，its distance with water supply piping，circulation water piping，fire fighting piping，water drainage piping and compressed air piping may be reduced to 0.5m，and its distance with control/telecom cable or optical cable in conduit may be reduced to 0.1m.
4　The values in the table are compiled in condition that water supply piping，circulation water piping and fire fighting piping are laid above sewage piping.The distance between potable water supply piping and sewage piping shall be increased by 50% based on the values in the table，The distance between production wastewater piping，rainwater trench（channel）and water supply piping，circulation water piping may be reduced by 20%.The distance between production wastewater piping，rainwater trench（channel）and control，telecom and electric power cable may be reduced by 20%，but it shall be no less than 0.5m.
5　When water supply piping，circulation water piping，fire fighting piping and drainage piping are jointly buried in sandy earth，and the material for water supply piping，circulation water piping and fire fighting piping is non-metal or nonsynthetic plastic，the distance between water supply piping，circulation water piping，fire fighting piping and drainage piping shall be no less than 1.5m.
6　The distance between thermal pipe trench（for heating only）and electric power cable，control/telecom cable or optical cable，cable trench may be reduced by 20%，but it shall be no less than 0.5m.
7　The distance between 110kV electric power cable with all sorts of pipelines in the table may be increased by 50% by the value of 35kV.The distance requirement for electric power cable duct（electric power cable）is the same with that for cable trench.
8　When oxygen piping is laid at the same level with acetylene piping of the same purpose，the distance between them may be reduced to 0.25m，but the height above those piping within 0.3m shall be filled compactly by sandy earth and loose earth and then backfilled with earth.
9　The distance between coal gas piping and production wastewater piping，rainwater piping refers to the partially filled piping.The distance may be reduced by 10% for filled pipe.The distance with covered drainagetrench（channel）shouldbeincreasedby10%.
10　The distance between natural gas piping and all sorts of piping in the table is the same as that of fuel gas piping.

Table 5.2.6　The minimum net horizontal distance between underground direct burial pipeline and architecture/structure，process facility and tank（m）

Notes:1　Unless specified in thetable，the distance for pipeline is calculated from pipe wall，trench wall，the external edge of protection facility or the outmost cable.The distance for urban road is calculated from the edge of road surface，and the space for highway road is calculated from the edge of road shoulder.
2　When drainage piping is pressure piping，the distance between it and external edge of the foundation of architecture/structure，process facility and tank shall be twice of the value in the table.
3　The distance between water supply，circulation water，fire fighting piping and railroad embankment toe should be no less than the height of embankment，and shall be no less than 5.0m.The distance between those piping and the top of railroad cutting slope should be no less than the height of the cutting，and shall be no less than 10.0m.The distance between drainage piping and railroad embankment toe，the top of railroad cutting slope should be no less than the height of road embankment or cutting，and shall be no less than 5.0m.
4　The distance between oxygen piping and external edge of the foundation of architecture with basement，the external edge of the accessible trench/road is:3.0m when oxygen pressure≤1.6MPa，5.0m when oxygen pressure＞1.6 MPa.The net distance between oxygen piping and external edge of the foundation of architecture without basement is:1.5m when oxygen pressure≤1.6MPa，2.5m when oxygen pressure＞1.6MPa.
5　The distance between acetylene piping and external edge of the foundation of architecture/structure with basement and fire hazard in Class A，process facility and tank with fire hazard in Class A，accessible trench/road is 3.0m.The distance between acetylene piping and external edge of the architecture without basement is 2.0m.
6　The distance between control/telecom cable，optical cable and external edge of the foundation of architecture/structure shall be 1.2m.The distance requirement for electric power cable duct（electric power cable）is the same with that for cable trench.
7　The distance between burial pipeline and foundation of architecture/structure，process facility，tank in the table refers to the case that the burial pipeline is in the same or above the elevation of the foundation of architecture/structure，process facility and tank.When the depth of burial pipeline exceeds that of the foundation of architecture/structure，process facility and tank，then the distance shall be decided the earth attribute，but it shall be no less than the value in the table.
8　The distance between HV（High Voltage）electric power pole/tower（the external edge of the foundation）and pipelines in the table shall be the distance of lighting，control/telecom poles increased by 50%.
9　When the foundations of dual column pipe rack are set up separately，the pipeline may be laid between the pipe rack foundations，but the specification in the table shall be complied with.

Table 5.2.8　Minimum net verticle clearance among different pipelines（m）

Notes:1　In case of sewage drainage piping containing acidic，basic or other corrosive substances crossing other piping（except corrosion-resistant piping），the net distance shall be no less than 0.5m，and the value in the table may apply when protection conduit is set up.
2　In the table，0.15m is the net verticle clearance when production water supply，circulation water and sewage drainage piping crosses.In case of crossing between domestic water supply piping and sewage drainage piping，and domestic water supply piping is above sewage drainage piping，the net verticle clearance shall be no less than 0.4m and there shall be no overlapped connection point.
3　In case that sewage drainage piping is laid above domestic water supply piping，other steel piping or cast iron piping，steel protection conduit or pipe trench shall be provided for water supply piping.The ID（Inner Diameter）of protection conduit or the net width of pipe trench shall be no less than the width of external edge of pipeline structure plus 300mm.The length of protection conduit or pipe trench should be no less than the foundation width of drainage piping above plus three times of the elevation difference for crossing piping，and should be no less than the foundation width plus 1.0m.The space between both ends of protection conduit or pipe trench and piping shall be sealed off by waterproof materials.The pipe trench may use mixed structure masoned by bricks or other materials.
4　For crossing between control/telecom cable or optical cable and fuel gas，acetylene or oxygen piping，in case of any connection point for those piping，the control/telecom cable or optical cable shall be sealed off.
5　In case of crossing between inflammable gas/liquid piping and other piping，the net distance may refer to that of acetylene piping.
6　The minimum net verticle clearance between direct burial electric power cable above 35kV and thermal piping shall be 1.0m.
7　The“—”in the table means no specification，and the value may be determined according to specific conditions.

Table 5.2.9　Minimum net horizontal distance between underground pipelines and trees

Note:Unless specified in the table，the pipeline is calculated from pipe wall or external edge of the protection facility，and the cable is calculated from the outmost one.