TRI is very active in the plastic pipe testing industry as an independent third party provider of quality assurance auditing and testing services.

TRI serves the Plastic Pipe Institute as the administrator of the PPI's Verification of Certification Program. In this role, TRI performs in-plant auditing of corrugated high density polyethylene pipe manufacturers to evaluate their compliance with governing quality control programs. In addition, TRI laboratories support both the PPI and National Transportation Product Evaluation Program (NTPEP) testing regimens. TRI provides the following laboratory tests on pipe and component resins.