National Emission Standards for Hazardous Air Pollutants for Semiconductor Manufacturing

This action promulgates national emission standards for hazardous air pollutants (NESHAP) for new and existing semiconductor manufacturing operations located at major sources of emissions of hazardous air pollutants (HAP). The final standards implement section 112(d) of the Clean Air Act (CAA), which requires the Administrator to regulate emissions of HAP listed in section 112(b) of the CAA. The intent of the standards is to protect public health and the environment by requiring new and existing major sources to control emissions to the level attainable by implementing the maximum achievable control technology (MACT). The primary HAP that will be controlled with this action include hydrochloric acid (HCl), hydrogen flouride (HF), methanol, glycol ethers, and xylene. Exposure to these substances has been demonstrated to cause adverse health effects such as irritation of the lung, eye, and mucous membranes; effects on the central nervous system; liver and kidney damage; and, possibly cancer. We do not have the type of current detailed data on each of the facilities and the people living around the facilities covered by today's final rule for this source category that would be necessary to conduct an analysis to determine the actual population exposures to the HAP emitted from these facilities and the potential for resultant health effects. Therefore, we do not know the extent to which the adverse health effects described above occur in the populations surrounding these facilities. However, to the extent the adverse effects do occur, and today's final rule reduces emissions, subsequent exposures will be reduced.