Addressing CIPP Safety Claims

Recent reports have questioned the safety of the CIPP process, specifically the use of styrenated resins with steam curing of the product. Please take the time to read this short synopsis of the situation, and make sure you know the facts.


WHO is making these claims?

  • The primary report we are responding to was published in July 2017 by Purdue University, and is titled Worksite Chemical Air Emissions and Worker Exposure during Sanitary Sewer and Stormwater Pipe Rehabilitation Using Cured-in-Place Pipe (CIPP).


WHY should I care?

  • Safety is our number one priority. Our intention in responding to these claims is to build upon the foundation of ASCE’s Code of Ethics’ First Canon – “To Hold Safety Paramount”.  
  • NASSCO and other industry leaders believe the Purdue report was published as a preliminary study and requires more conclusive research.
  • Fear tactics are being directed to engineers and municipalities by individuals who could benefit if CIPP systems required the incorporation of their products in the future.
  • Since the Purdue report was published, more cities and other utilities are asking NASSCO about the safety of the CIPP process.
  • Our ultimate goal is to leave no stone unturned in the discovery of facts pertaining to the properties and outcomes of CIPP. Without this discovery and pursuit of truth, an entire segment of our industry could be negatively affected in the following ways:
    • Municipalities – may need to consider more costly replacement solutions, including dig and replace, with significantly higher disruption and environmental impacts.
    • Contractors – may experience a loss in revenue if demand for CIPP goes down, driving up costs.
    • Engineers – may need to specify rehabilitation technologies that do not perform as well as CIPP and, in some cases, are proprietary.
    • Manufacturers – could be negatively affected if demand drops for equipment, materials and supplies required for CIPP installations, driving up costs.
    • Entire Communities – could suffer if this nearly 50-year old proven technology is replaced with other solutions that are more disruptive and less ecologically/environmentally responsible.
  • There is not a technology that can replace the volume of pipes currently being rehabilitated using CIPP. Sewers that need to be rehabilitated would be put on hold, while suffering from infiltration and exfiltration, overflows and higher treatment costs.


WHAT is NASSCO doing about it?

  • We have formed a workgroup with other industry leaders including National Sanitation Foundation (NSF), the North American Society for Trenchless Technology (NASTT), American Composites Manufacturing Association (ACMA), the Water Research Centre (WRc) and the Water Environment and Reuse Foundation (WE&RF), among others.
  • We are facilitating a formal review of the Purdue study, as well as other studies on the topic, to include additional sampling and analysis of emissions during the field installation of CIPP using the steam cure process.
  • Research will be peer-reviewed to challenge or confirm the Purdue report. We will honor the findings and act accordingly.
  • The study will be conducted by a third-party group consisting of academia in conjunction with a professional environmental consultant with knowledge and experience in CIPP technology.
  • We are updating our “Guideline for the Use and Handling of Styrenated Resins in Cured-in-Place Pipe” to provide best practices for contractors to mitigate potential risk.

HOW can I help?

  • Know the facts and be prepared when you are approached by media and others who may question the safety of CIPP. Do not guess – if you need help responding, call on us to help.
  • Read this short article:
  • Follow NASSCO’s LinkedIn and Facebook pages and share our posts pertaining to this subject on your personal and corporate social media sites.
  • Email Mayank Khurana at [email protected]  if you encounter questionable articles or negative sales tactics on the subject.

WHERE can I learn more?

  • The “What’s New” section on the home page of is continually updated with the latest news on the subject.