Health hazard evaluation report: HETA-2005-0024-3000, United Technologies/Carrier Corporation, Indianapolis, Indiana.
On November 11, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a request from the United Steelworkers of America, Local 1999, for a Health Hazard Evaluation (HHE) at the United Technologies/Carrier Corporation, Indianapolis, Indiana. Plant workers were experiencing gastrointestinal illness, sinus problems, headaches, rashes, eye irritation, and breathing problems associated with a metal stamping and washing operation (7 128 HX washer) and an associated testing procedure called a run-test (7 128 run/test). On January 12, 2005, NIOSH industrial hygienists collected bulk water and sludge samples at the suspect 7 128 HX washer, and at two similar production lines where no problems had been reported. A NIOSH medical officer interviewed workers from the affected area. Two bulk water samples from the suspect operation contained enteric bacteria in concentrations up to 10,000,000 (1.0 x107) colony forming units/milliliter (CFU/ml). Enteric bacteria are normally found only in the intestines of animals and are an indicator of fecal contamination. Aeromonas hydrophila, a bacterium widely found in the aquatic environment and capable of causing gastroenteritis in healthy individuals, was also identified. The two comparison machines had no evidence of enteric contamination. After obtaining these results, plant management reported that they had disconnected and capped a drainage pipe linking the machine to a sewer line and cleaned the machine with a 1/100 dilution of sodium hypochlorite/water. Despite the repairs and cleaning, follow-up water samples taken from the contaminated machine on February 1, 2005 and March 16, 2005, by NIOSH investigators found enteric bacteria levels similar to previous samples. During the February site visit, 20 employees working on or near the suspect operation completed a questionnaire. Eight reported gastrointestinal illness during the prior 6 months. Stool samples were collected on three employees who reported diarrhea, and one grew Aeromonas veronii biovar sobria, which is associated with diarrhea. The stool bacterium was the same genus but a different species than that found in the bulk water samples from the 7 128 HX washer. On March 16-17, 2005, personal breathing zone air samples for volatile organic compounds, carbon monoxide, and aldehydes were collected at the 7 128 run/test line. Although results were within occupational exposure limits, some of the compounds identified could be respiratory irritants. In addition, the smoke produced during furnace testing was not entirely captured by the local exhaust hood when the furnace blower was engaged. Over two thirds of the 7 128 run/test employees surveyed reported work-related eye and/or nose irritation, cough, and headache in the 2 months prior to the NIOSH survey. NIOSH investigators determined that a health hazard existed in the 7 128 HX metal stamping and washing operation due to fecal contamination of the rinse water. Employees working in this area reported a high prevalence of gastrointestinal symptoms, including diarrhea. Employees at the 7 128 run/test line reported eye and upper respiratory irritation, which was likely related to the smoke produced during furnace testing. Recommendations were to hire an experienced cleaning contractor to disinfect the 7 128 HX stamping and washer machines, modify the run/test procedures, educate employees on improved hygiene and personal protective equipment (PPE) use, and improve the ventilation at the 7 128 run/test line.