Pressure Testing (HDS)


NSF has the largest hydrostatic testing capacity in North America. We utilize standard pressure testing methodologies to determine a material’s hydrostatic design basis (HDB) and hydrostatic design stress (HDS). These test methods allow NSF to forecast the long-term material strength to help ensure safe use in the field.

HDB: The categorized long-term hydrostatic strength (LTHS) in the circumferential or hoop direction, for a given set of end use conditions as established by ASTM D2837.

HDS: The recommended maximum hoop stress that can be applied continuously with a high degree of certainty that pipe failure will not occur.

We currently test to:

  • ASTM D1598 – Standard Test Method for Time-to-Failure of Plastic Pipe Under Constant Internal Pressure
  • ASTM D1599 – Standard Test Method for Resistance to Short-Time Hydraulic Pressure of Plastic Pipe, Tubing, and Fittings
  • ASTM D2837 – Standard Test Method for Obtaining Hydrostatic Design Basis for Thermoplastic Pipe Materials or Pressure Design Basis for Thermoplastic Pipe Products
  • ISO 9080 – Plastics piping and ducting systems – Determination of the long-term hydrostatic strength of thermoplastics materials in pipe form by extrapolation
  • CSA B137.0 – Definitions, General Requirements, and Methods of Testing for Thermoplastic Pressure Piping

Contact for more information.

Why Work with NSF?

The role plastic piping plays in the distribution of gas, drinking water and wastewater is essential. To verify plastic piping products have met required durability, performance and safety criteria for use in commercial and residential applications, they are tested and certified to internationally-recognized standards. NSF, a global provider of testing and certification, has served for the plastic pipe industry for nearly 50 years. NSF developed the American National Standards for pipes and other products that treat or come into contact with drinking water and certified more than 60,000 products to these standards.


NSF plastic pipe clients now have access to the strongest combination of consulting and laboratory technical expertise through an agreement with Jana, a project-based consulting firm that serves the global water and plastic pipe industries, to benefit both organizations’ clients. With this agreement, Jana will be able to provide independent consulting services to NSF clients and NSF will be able to provide testing services to Jana’s clients. The two organizations also will work together in the development of new standards.