IRVING, Texas - A new standard focusing on high-density polyethylene (HDPE) conduit has been published by the American Association of State Highway and Transportation Officials (AASHTO).
The "Standard Practice for Solid Wall High-Density Polyethylene Conduit for Non-Pressure Applications Used for the Protection of Power and Telecommunications Cables" covers material, dimensional, workmanship and performance requirements. Known as AASHTO "Standard Practice R 63", it provides guidance in the specification of HDPE conduit used in buried applications for the protection of power and communications cables. Communication applications include ITS (Intelligent Highway Systems), CCTV (Closed Circuit TV), and fiber optic cables along highway rights of way. SCADA (Supervisory Control and Data Acquisition) applications included pipeline control, Positive Train Control Technology, and Traffic Control and Monitoring. Highway and airport lighting, electrical distribution and transmission lines are some of the power applications.
"This document by the AASHTO Materials Sub Committee 4b makes it possible to standardize on material specifications and insure compliance with other standards governing electrical and fiber optic cable systems," stated Tony Radoszewski, executive director of the Plastics Pipe Institute, Inc. (PPI). "The PPI Conduit Division worked closely with AASHTO materials engineers to optimize specifications and requirements for HDPE conduit which protects the nation's power grid and information highway.”
The standard identifies typical installation methods that include trenching, plowing and Horizontal Directional Drilling (HDD). Detailed design information on installation can be found in the PPI "Handbook of Polyethylene Pipe" and other Technical Notes (TN) located on the PPI website.
The AASHTO document explains that HDPE conduit is a protective pathway for telecommunications and power cables used throughout the infrastructure. The inherent properties of HDPE such as chemical resistance and stress crack resistance are well-suited for infrastructure systems since these require long service life. Because of HDPE coilable conduit's long lengths, flexibility, and tensile strength, it is ideally suited for HDD and plowing installation methodologies that have minimal impact on traffic and the surrounding infrastructure. HDPE conduit is also available in 20- to 40- foot length 'sticks' in larger diameters above six inches for installations requiring multiple pathways (innerducts) to run through one service pathway.
Participating members from the PPI Conduit Committee included Jennifer Marin of Endot Industries, Inc.; Sarah Patterson, who was then with Dow Chemical and is now PPI's technical director; Tom Stewart of the Dura-Line Corporation; George Zagorski, Blue Diamond Industries; and PPI's Tony Radoszewski along with industry consultant Jim Goddard, and Bill Bailey of the Virginia Department of Transportation (VADOT) and also chairman of the AASHTO Technical Section on Flexible Pipe. PPI is the major trade association representing all segments of the plastic pipe industry.
"I would personally like to thank Bill Bailey from VADOT for recognizing the need for this standard practice and allowing us to participate in its development." said Radoszewski. "We were also fortunate to have Jim Goddard as an advisor. His long experience with AASHTO standards on large diameter corrugated pipe for storm water management systems was invaluable.”
"This document was the first step in adapting requirements for HDPE conduit that were originally based on the properties of PVC conduit," he explained. "Our members volunteered their time to determine the proper communications channels, assemble the facts and protocols and present the findings to the AASHTO Materials Sub Committee 4b. This project exemplifies the collaborative nature of the PPI to benefit the industry, communities and citizens by making available proven and effective products which have been vetted by well-respected organizations such as AASHTO."
Additional information can also be found on the PPI website: www.plasticpipe.org.