Thermoplastic Pipe

Plastic pipe is intended for surface and subsurface drainage applications where soil provides support to its flexible walls. Its major use is to collect or convey drainage water by open gravity flow, as culverts, storm drains, etc.

Currently, NTPEP is auditing HDPE (High Density Polyethylene) Thermoplastic Pipe manufacturers, which includes split sample testing. Audit and test protocols are described in the “Project Work Plan.” All audit requirements conform with the latest version of AASHTO Standard Specifications (M 252 and M 294).

The NTPEP Technical Committee responsible for authoring the Project Work Plan convenes yearly at the NTPEP National (Annual) Meeting. During this working meeting, the Project Work Plan is discussed, changes made, and shortly thereafter balloted for adoption. Improvements are immediately implemented in the next available audit tour. When compared to other standards development exercises, the NTPEP process is agile, effective and efficient.

NTPEP Designated Lab:

  • TRI Environmental
  • PSI Lab

NTPEP - Thermoplastic Pipe

Committee Name:
NTPEP-Technical Committee on Thermoplastic Pipe
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Work Plan

NTPEP tests products according to a Project Work Plan, which describes the laboratory and/or field test protocols used to conduct the evaluation. The Project Work Plan is a consensus-based document and includes peer review and input from industry experts. Each Project Work Plan is adopted after receiving at least two-thirds affirmative support from 52 AASHTO member states. When implemented by state DOTs, their own state standard specifications may supersede the NTPEP Project Work Plan. Industry is advised to be aware of state-level requirements, which may supersede basic NTPEP testing.


Audit Documents

Please visit the NTPEP Audit Documents web page for blank audit reports.

Please go to NTPEP DataMine.

Please go to NTPEP DataMine.

Industry Resources

Associations that would like to be affiliated with the NTPEP Thermoplastic Pipe program should contact Matt Bluman ( for additional information.