WAC 296-96-02550   What are the requirements for underground hydraulic elevator pipes, fittings, and cylinders?  All newly installed underground pressure cylinders and pipes containing hydraulic elevator fluids shall be encased in an outer plastic containment.

     (1) The plastic casing shall be constructed of polyethylene or polyvinyl chloride (PVC). The plastic pipe wall thickness must not be less than 0.125 inches (3.175 mm). The casing shall be capped at the bottom and all joints must be solvent or heat welded.

     (2) The casing shall be sealed and dry around hydraulic pipe and cylinder to contain any leakage into the ground and to prevent electrolysis to the hydraulic pipe and the cylinder. Dry sand may be used to stabilize the hydraulic cylinder.

     (3) A one-half inch pipe nipple with a one-way check valve shall be located between the casing and cylinder for monitoring purposes.

     (4) Alternate methods must receive approval from the department prior to installation.

     (5) This rule shall apply to all conveyances with installation permits issued by the department on or after 01/01/1993.



[Statutory Authority: Chapter 70.87 RCW. 07-24-041, § 296-96-02550, filed 11/30/07, effective 1/1/08.]