Purdue Study Raises Safety Concerns about CIPP Steam Venting

Collection Systems, Emerging Issues

Support for coverage of safety issues in provided by ehs 


According to a Purdue Engineering Department study released last month there are potentially volatile organic compounds and other toxic gasses in the steam venting from the cured-in-place-pipe process. Are workers and the public safe?

From Purdue’s news release:

 New research is calling for immediate safeguards and the study of a widely used method for repairing sewer-, storm-water and drinking-water pipes to understand the potential health and environmental concerns for workers and the public.

The procedure, called cured-in-place pipe repair, or CIPP, was invented in the 1970s. It involves inserting a resin-impregnated fabric tube into a damaged pipe and curing it in place with hot water or pressurized steam, sometimes with ultraviolet light. The result is a new plastic pipe manufactured inside the damaged one. The process can emit chemicals into the air, sometimes in visible plumes, and can expose workers and the public to a mixture of compounds that can pose potential health hazards, said Andrew Whelton, an assistant professor in Purdue University’s Lyles School of Civil Engineering and the Environmental and Ecological Engineering program.

Continue reading about Purdue’s study…


Update 8/17/17

In response to the Purdue Study, the National Association of Sewer Service Companies has released their analysis of the research and believe the researchers did not follow proper protocols. Here’s a portion of NASSCO’s response

It is clear that NASSCO guidelines and specific quality and safety protocols were not utilized during the testing performed, nor referenced in the study by the University.

This is of great concern to NASSCO and other organizations aligned to our industry that continually use, monitor and evaluate the effectiveness and safety levels of CIPP technology.  It is difficult for us to understand how a representative team from a reputable University would not fact check their information and assumptions before publishing such critical information to the public.

Purdue University proceeded to publish the same disputed information and additional findings without any apparent peer review, and did not include the resources readily available from NASSCO. Further, there was still no communication with NASSCO or, to our understanding, other organizations that could have provided excellent feedback and supportive data to provide a more accurate portrayal of CIPP technology.

A review of the data released in the initial Purdue study indicated a number of inconsistencies that had not been experienced or documented previously in the industry. This is based on extensive testing performed around the world. To our understanding, these data were not considered before coming to a final conclusion or publication of the report.

Read NASSCO’s complete response here

Where do you stand on the safety of the CIPP steam curing process?  Let us know in the comments section below. We’ll be sure to keep folks up to date as this story progresses.

Update 9/12/17

In a public notice unrelated to Purdue’s study the California Department of Public Health recently warned contractors should manage CIPP vapors carefully…

There is a possibility of residual chemical releases with CIPP processes. Most of the studies relating to residual chemical releases have focused on environmental impacts from styrene, however migration of vapors and potential impacts on indoor air are also important to consider.

Download the “CIPP Safety Alert” here >


Update 10/19/17

NASSCO has formed a work-group to analysis Purdue’s findings. They have also announced an independent study by academia and consulting engineer representatives into the safety of CIPP installation procedures.

This workgroup has reviewed the study — along with other articles, social media posts, webcasts and interviews — and based on the information available, has determined that claims made regarding the safety of steam-cured CIPP installations are premature and certainly not conclusive.

Read about NASSCO’s Work Group and the third-party investigation >