Health hazard evaluation report: HETA 2002-0418-2912, Richards Industries, Cincinnati, Ohio.
On September 20, 2002, the National Institute for Occupational Safety and Health (NIOSH) received a management request for a health hazard evaluation (HHE) at Richards Industries in Cincinnati, Ohio. The request centered on workers' exposures to paint, catalyst, and thinner during spray painting operations. On October 8, 2002, NIOSH investigators conducted an exposure assessment that included personal breathing zone (PBZ) and general area (GA) samples for methyl ethyl ketone (MEK), toluene-2,4-diisocyanate (TDI), and other volatile organic compounds (VOCs). Qualitative samples were collected with thermal desorption tubes to determine the appropriate VOCs for analysis. MEK and TDI were chosen for sampling because of their presence in paint components. The October 8 site visit also included a local exhaust ventilation (LEV) assessment of the paint booth using a velometer and smoke tubes and a medical survey of employees working in and around the Paint Department. Based upon the samples collected with the thermal desorption tubes, the PBZ and GA samples were analyzed for toluene, butyl acetate, propylene glycol methyl ether acetate (PGMEA), cyclohexanone, limonene, and total hydrocarbons (reported as decane). Toluene ranged from 0.004 to 0.34 parts per million (ppm), butyl acetate ranged from 0.02 to 0.57 ppm, PGMEA ranged from 0.03 to 0.58 ppm, cyclohexanone ranged from trace to 0.59 ppm, limonene ranged from 0.02 to 0.07 ppm, and total hydrocarbons ranged from 0.28 to 0.3 7 ppm. The MEK results ranged from 0.15 to 31 ppm, and the TDI monomer results ranged from not detected to 0.06 parts per billion (Ppb). All of these results were below applicable occupational exposure limits. The ventilation assessment revealed that air flow into and out of the paint booth was below recommended standards. Air flow within the drying booth was inadequate, and the air over the mixing table was stagnant. Employees in and near the Paint Department reported, during confidential medical interviews, that they had experienced a variety of health effects, including headache, anxiety, and respiratory problems. They believed these health effects to be either caused or worsened by workplace exposures. The cause(s) of the reported symptoms could not be determined by NIOSH investigators. Although air sampling did not identify any over-exposures, ventilation within the Paint Department did not meet minimum airflow velocity requirements. Recommendations are provided to further reduce employees' exposures to these chemicals by improving ventilation and by the appropriate use of personal protective equipment.