THE STYRENE INDUSTRY’S 20PPM RECOMMENDED STYRENE WORKER EXPOSURE LIMIT BRIEFING AND FEEDBACK

HISTORY OF STYRENE WORKPLACE EXPOSURE LIMIT 1989 OSHA adopts ACGIH LTVs for many chemicals Styrene 8-hour PEL changed from 100ppm to 50ppm and 15-minute short-term limit from 200ppm to 100ppm 1993 US Court overturns new PELs on procedural grounds Styrene PEL reverts to 100ppm 8-hr and 200ppm 15-minute 1997 ACGIH revises the styrene 8-hour TLV from 50 to 20ppm, based on studies showing mild color vision effects below 50ppm 1997 ACMA, NMMA and SIRC adopt a voluntary 8-hour limit of 50ppm and 15-minute limit of 100ppm, in response to data showing mild nervous system effects above 50ppm 2004 Cal-OSHA committee recommends change in 8-hour limit from 50ppm to 5ppm or less SIRC and ACMA argue that the committee process is flawed Cal-OSHA agrees and starts to revise PEL process

HISTORY OF STYRENE WORKPLACE EXPOSURE LIMIT (CONT.) 2007 Cal-OSHA starts PEL updates using revised process Styrene is placed in 2 nd group of substances for PEL review 2009 Large industry study at German boat plant finds mild hearing loss in long-term workers exposed above 30ppm Other worker studies show nervous system toxicity below 50ppm Studies with laboratory animals show hearing loss at levels equivalent to 40ppm in humans 2010 European styrene industry submits 8-hour 20ppm and 15-minute 70ppm worker exposure risk management level to EU regulators 2011 Based on comments received via a website poll, US OSHA informally identifies styrene as a priority substance for PEL update 2011 SIRC Steering Committee approves position of industry toxicologists to recommend an 8-hour styrene OEL of 20ppm and 15-minute limit of 70ppm

WHY IS THE SIRC RECOMMENDATION IMPORTANT? The best available scientific review Based on multiple studies of workers and laboratory animals Concluded that long-term workers exposed above 30ppm (inhalation) may suffer a mild acceleration of normal age-related hearing loss Cal-OSHA and US OSHA are likely to accept the SIRC recommendations as a starting point in PEL updates o Both agencies have styrene on a target list for updates

OPTIONS FOR COMPANIES Evaluate compliance options: o Process and chemistry changes o Production floor reconfiguration o Ventilation design o Job rotation o Respiratory protection, including new technologies Participate in industry discussion

ACMA'S IMMEDIATE RESPONSE TO OEL Inform the industry of the SIRC action ACMA asked SIRC to include a "3-5 year phase-in period" for compliance with 20ppm Help the industry evaluate compliance options o Webinars o Special programming at COMPOSITES Collect industry input to inform ACMA Board response to OEL

QUESTIONS? COMMENTS? SUGGESTIONS?