Holiday Rambler met with members of the Indiana Pollution Prevention and Safe Materials Institute (IPPI) in August of 1995 to discuss ways in which the Institute could assist the company with its ongoing pollution prevention projects.
Holiday Rambler (and its Utilimaster division) had embarked on a pollution prevention-based adhesives replacement program which involved switching from a high-HAP (hazardous air pollutant)-based adhesives to a non-VOC (volatile organic compound), non-HAP emitting adhesive such as a thermosetting urethane, thermoplastic hot melt and/or water-based adhesives.
Holiday Rambler (now a division of Monoco Coach) is based in Wakarusa, Indiana. Holiday Rambler is internationally recognized as a quality manufacturer of high-end motor homes and recreational vehicles (RVs). The Wakarusa facility produces class A motor homes as well as towables (both fifth wheel and traditional tandems).
Holiday Rambler pioneered the use of the automotive-fashion, seamless fiberglass laminate as the exterior skin of their class A and towable RVs. The fiberglass laminate offers not only a high quality automotive look, it also is very resistant to outdoor weathering and offers years of outstanding performance.
The company had been using a special industrial grade, high-HAP adhesive, containing 76% of 1,1,1-trichloroethane (a listed hazardous air pollutant) and 2.3% 1,3-dioxolane (a listed HAP and a VOC). The adhesive anchors the fiberglass laminate to the exterior of the RV's body as well as anchors walls and insulation to the vehicle's interior. The high-HAP adhesive, generally known as red glue, is also used to anchor many other items in the vehicle's construction, such as carpets, tabletop laminates, curtain valances, wood fixtures, and dashboard padding. The red glue has been the adhesive chosen by many RV manufacturers because of its fast-dry and strong, immediate adhesion characteristics. The glue is so versatile that wherever a bond is needed, the red glue is used.
The fiberglass laminates are placed horizontally under a red glue spray nozzle and receive a coat of the glue. The RV's aluminum superstructure, to which the laminate will be anchored, is also sprayed with the glue. The laminate is laid over the superstructure and the combined unit is then passed through a press roller which activates the red glue's pressure-sensitive bond. Interior walls are then anchored to the laminate/superstructure unit in a similar manner, again using the red glue.
Carpets, valances, miscellaneous insulation, and dashboard padding are applied at separate production stations. This procedure involves manual spray application of the red glue.
The 1990 Clean Air Act carries stiff new air pollution regulations, which are just beginning to affect American industry. The law has a specific provision for a special class of pollutants called hazardous air pollutants (HAPs). The Environmental Protection Agency (EPA) is developing special air emissions limits, rules, and regulations (specifically for HAPs) called Maximum Achievable Control Technology (MACT) standards. These new MACT standards will impose strict controls on specific industry sectors. The EPA has not, as yet, promulgated a specific MACT standard for the RV industry; therefore, Holiday Rambler is moving far ahead of the regulatory curve by switching from the HAP-containing red glue adhesive.
The newly adopted adhesives, used as a replacement for 1,1,1-trichloroethane-based red glue, emit no HAPs/VOCs, reduce or eliminate exposure of workers to toxic compounds, and offer improved adhesive bond performance. The Institute performed an industrial hygiene assessment of worker exposure pertaining to the urethane adhesive used in the sidewall and exterior process. This adhesive contains 2% methylene bisphenyl diisocyanate (also known as MDI), itself a hazardous compound. The worker exposure tests were performed under actual production conditions. The MDI serves as an adhesive cross-link activator which becomes part of the adhesive and is not emitted to the air. The results of the tests demonstrated that there was no employee exposure to MDI above the OSHA Permissible Exposure Level (PEL). In fact, no detectable level of MDI was found during the performance of the industrial hygiene survey.
Holiday Rambler made a corporate commitment to eliminate the high-HAP-emitting glue and began its project in early 1995. The company had selected a non-HAP/VOC-emitting urethane adhesive to replace the red glue in the RV lamination department and a non-HAP/VOC-emitting thermoplastic hot melt for the Utilimaster lamination department. The company had not decided on the preferred, non-HAP/VOC replacement for the adhesion of the carpets, insulation, dashboard padding, etc., to the RV.
The Indiana Pollution Prevention and Safe Materials Institute began work with the company by reviewing various water-based and hot melt products with regard to their appropriateness to the demands inherent in Holiday Rambler's production process. The Holiday Rambler/IPPI team developed test methods and qualification procedures which could be used to mimic production-based application and adhesion demands. The tests showed that the thermoplastic hot melt used by Utilimaster and a spray water-based adhesive were best suited to replace the venerable, red glue for the production stations.
The company then chose the water-based adhesive for all RV applications involving valances, storage bays, dashboards, etc. A key advantage the water-based adhesive has over the hot melt adhesive is that the water-based adhesive can be sprayed easily from simple, hand-held spray guns. The hot melt adhesive requires heating equipment, heated delivery hoses, and heated spray guns, which add to the system's application costs. However, the application and bond of the hot melt was excellent.
POTENTIAL ENVIRONMENTAL AND COST BENEFITS In 1995, Holiday Rambler emitted 116.8 tons of 1,1,1-trichloroethane (TCA) and five tons of miscellaneous VOCs into the air as a direct result of the red glue adhesive. Utilimaster, a commercial vehicle (CV) manufacturing division of Holiday Rambler, emitted 13.9 tons of TCA as a result of their "red glue" usage. The current estimate of 1996 TCA air emissions from all RV and CV laminating operations is .65 tons per year, representing a 98.5% reduction of TCA air emissions. The 1997 production schedule will completely eliminate the company's use of TCA.
The urethane and water-based adhesive replacements are 20-30% more expensive than the previously used red glue adhesive on a per gallon basis. However, the new urethane-based adhesive is 100% solids and, therefore, it is more efficient in coverage rate (per gallon) than the red glue. This contributes to the urethane being approximately 50% less expensive than the red glue.
The following is a breakdown of the estimated savings stemming from the conversion to the urethane thermoplastic hot melt and the water-based adhesives.
Holiday Rambler has made modifications and new equipment purchases in excess of $900,000 in order to convert to the new urethane adhesive. The company has not finalized the formal analysis of product quality enhancement value and/or annual system maintenance costs, but the company believes that savings associated with heat and ventilation costs, reduced adhesive usage, product quality enhancement, employee respirator costs and training, as well as hazardous waste disposal, will provide a payback estimated at 3.4 years. This project eliminates more than 131 tons of the hazardous air pollutant emissions and dramatically improves worker safety, which more than justifies the estimated 3.4 year payback.
Holiday Rambler made the corporate commitment to discontinue the use of the red glue lamination adhesive, which was a major contributor to its hazardous air pollutant emissions. The company succeeded in reducing its emissions of TCA by over 99% and is preventing the emissions of 131 tons of TCA to the environment as well as reducing the exposure of its employees to hazardous compounds. The company continues its drive to dramatically reduce other HAP emissions and is now engaged with the Indiana Pollution Prevention and Safe Materials Institute to analyze closed-mold, light tooling, which may dramatically reduce styrene emissions from the traditional, open-mold, fiberglass shell production process. The company applied for and received moneys from the Indiana Department of Environmental Management's OPPTA (Office of Pollution Prevention and Technical Assistance) to fund the new, innovative, closed mold process. Holiday Rambler is committed to quality and to pollution prevention. This successful project demonstrates that the company is not only an industry leader in RV design and construction, but also in corporate environmental responsibility. 3 (c)Purdue University Research Foundation, 1996