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
Annual meeting minutes are combined with attendance sheets and, if available, presentations.
Please note: HDPE Pipe merged with PPP and PVC Pipe and formed the Thermoplastic Pipe Technical Committee in 2015.
2021 Summer Conference Call June 15, 2021
2021 Spring Conference Call – March 18, 2021
2020 Winter Conference Call – December 9, 2020
2020 Summer Conference Call
2020 Annual Meeting Virtual
2020 Spring Conference Call
2019 Fall Conference Call
2019 Summer Conference Call
2019 Annual Meeting Big Sky, MT
2018 Summer Conference Call
2018 Annual Meeting Norfolk, VA
2017 Annual Meeting Boston, MA
2017 Winter Q1 Conference Call
2016 Winter Q4 Conference Call
2016 Summer Conference Call
2016 Annual Meeting Grand Rapids, MI
2016 Winter Q1 Conference Call
2015 Summer Conference Call – August 11, 2015
2015 Annual Meeting Scottsdale, AZ
2014 Annual Meeting Greenville, SC
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.
- Project Work Plan for HDPE Pipe (HDPE-20-01)
- Project Work Plan for Polypropylene Pipe (PPP-20-01)
- Project Work Plan for PVC (PVC-20-01)
Please visit the NTPEP Audit Documents web page for blank audit reports.