NASSCO Releases Guidelines On Styrenated Resins

NASSCO (National Association of Sewer Service Companies) has completed a state of the art guideline for the use and handling of styrene based resins in the cured in place pipe (CIPP) rehabilitation process.

The report, based on a study by the NASSCO CIPP Committee, is titled Guideline for the Use and Handling of Styrenated Resins in Cured In Place Pipe, can be downloaded at no cost from the NASSCO web site,

Contents of the guideline includes:
• Facts about resin materials used for CIPP;
• Receiving, storing and handling of CIPP resins and initiation of chemicals;
• Transporting resin saturated tubes;
• CIPP installation practices; and
• Water and steam curing.

“Until now, there has been no document providing a well researched guideline for the proper handling and use of styrenated resigns in CIPP linings,” said Ed Kampbell, a member of the committee and principal author of the guideline. “NASSCO determined that such a guideline is needed due to the increasing number of CIPP projects, the expansion of CIPP into other areas such as storm sewers, and especially with some public concern about harm to the environment.”

Addressing concerns

Concern over the potential of releasing styrene into the environment related to projects using styrenated resins during CIPP applications was a primary factor considered during the eight month study by the committee.

“It is important to understand,” said Kampbell, “that styrene use related to CIPP is a much different type of environmental risk than in other resin using industries such as boat manufacturing which potentially can send large qualities of styrene into the air and their surface water discharges.”

The guideline states that styrenated resin systems as they are currently used today in CIPP rehabilitation systems produce a safe and environmentally sound solution to the challenges of restoring the nation’s failing infrastructure. The risk associated with styrene’s use in CIPP is minimal and well within the Clean Water Act’s original intent of keeping the environment as free as is practical of chemical pollutants. CIPP installation sites managed with “good housekeeping” will present little opportunity for human health risks and/or environmental risks.

The guideline sites a history of successful and safe usage of styrenated CIPP lining. In addition, it makes a strong case for styrenated resin CIPP usage.

Best material

“Styrene,” says the guideline, “is the ideal monomer used for cross linking polyester and vinyl ester resins. Although alternative monomers have been extensively investigated, none of those monomers have matched the overall performance of styrene. Polyester and vinyl ester resin systems have been used for more than 35 years in CIPP. During this time frame there have been no noted serious consequences to their usage in CIPP . . .

“Over the last 30 years, the increasing awareness of the need to limit the effects of styrene exposure has led the polyester resin processing industry to pursue strategies to reduce exposure in the manufacturing and processing plant environment. Most, if not all of the studies undertaken to date, have centered on these producer and user environments which are dramatically different than the work environment of the CIPP installation contractor.”

The guideline continues that because no definitive document for these resin systems as used in this specific application existed, the unknown has lead to speculation as to their safety with respect to the work force involved, the general public when the odors enter the structures connected to the piping under rehabilitation, and to the greater downstream environment from where the work is taking place.

The report says that NASSCO created a styrene task force to review the technical information available from these studies and current CIPP installation practices to produce this CIPP specific guideline. In addition to this guideline, NASSCO has prepared an Inspector Training Course to properly equip the owner and the project engineer with the necessary knowledge to ensure that a proper installation is achieved which will minimize the potential for release of styrene to the environment.

NASSCO is a national organization composed of several hundred members representing rehabilitation industry manufacturers and suppliers, municipalities and utility districts, engineers and contracting firms.

NASSCO CIPP Committee members

Members of the NASSCO CIPP Committee that developed the guideline for using styrenated resins for cured in place pipe applications are:

Chairman Lynn Osborn, Insituform Technologies; Ed Kampbell, Rehabilitation Resource Solutions; Marc Anctil, Logiball; Irv Gemora, NASSCO executive director; Steve Gearhart, CIPP Corp.; Geoff Yothers, Inliner Technologies; Greg Laszczynski, Mississippi Textiles; Gerry Muenchmeyer, Muenchmeyer & Associates; Kaleel Rahaim, Interplastic Corp; Jim Harris, City of Murfreesboro, TN; and Larry Kiest, LMK Enterprises.

NASSCO, (410) 486-3500,

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