API PUBL 4629:2007

This report details the findings from an air sampling survey contracted by the American Petroleum Institute (API) to evaluate inhalation exposures to hexavalent chromium (chromium (VI)) during seven types of hot work: carbon arc cutting (CAC), flux cored arc welding (FCAW), gas metal arc welding (GMAW or MIG), grinding, gas tungsten arc welding (GTAW or TIG), oxyfuel gas cutting (OFC or torch cutting), and shielded metal arc welding (SMAW or stick). Eighty-three samples were collected in October and November 2005 at two petroleum sites during maintenance turnarounds by API member companies. An additional 188 samples were collected April - June 2006 at three different petroleum company sites by ICU Environmental Health and Safety. Of the 271 total samples, 63 samples were at or above the Occupational Safety and Health Administration (OSHA) action level of 2.5 ug/m3 and 51 were at or above the OSHA permissible exposure limit of 5 ug/m3.