Opportunity: Industrial fabrication processes frequently involve potentially hazardous chemicals. In the laminated plastics industry, which produces recreational boats, bathtubs and shower stalls, laboratory fume hoods, truck parts and many other goods, exposure to styrene is common. Styrene can enter the body by inhalation, ingestion and absorption through the skin. Styrene exposures cause eye and nose irritation, and long-term exposures can cause neurological damage. Additionally, styrene is considered a possible carcinogen, and the federal standard for an 8-hour time-weighted average exposure is 100 ppm. An estimated 30,000 workers in 1,000 plants are exposed to styrene regularly. Despite efforts to develop processes and engineering controls to minimize styrene liquid and vapor contact, many exposures remain directly related to the work practices which are followed.
Performance Excellence Audit: Plant tours, surveys and interviews with several manufacturing facilities revealed several practices which contributed to unnecessary styrene exposures:
Operating and Management Process Improvements: Production and housekeeping processes were analyzed to identify steps in which the greatest potential exposures occurred. Work practices were redesigned to minimize potential exposures. A series of mastery-based training videotapes were developed, and were presented to workers over several weeks. Each tape presented a recommended work practice or procedure by explaining its purpose and importance, then provided a visual demonstration of its proper utilization. Following training, on-the-job evaluation of the use of the new work practices was conducted, and small monetary incentives were provided for achieving mastery of new work practices and housekeeping conditions. Process assurance was enhanced to incorporate supervisors' delivery of positive recognition and corrective feedback to workers on their use of the new work practices. Housekeeping and equipment maintenance checklists were developed and progress was graphed and displayed daily.
Results: Workers' use of proper work practices increased from baseline levels ranging from 49% to 76% to a post-intervention level of nearly 100% for all plants. Housekeeping conditions improved from baseline levels of 15-40% to post-intervention levels of over 90%. Improvements in work practices and housekeeping conditions resulted in reductions of airborne styrene vapor ranging from 38-89%. Reductions in individual breathing-zone exposures ranged from 36-57%. It is important to note that these improvements resulted directly from changes in worker performance, without adverse impacts on production and without extensive ventilation engineering.
April 13, 2008.
Copyright © 2008 Conard Associates, Inc.