This action promulgates national emission standards for hazardous air pollutants (NESHAP) for plastic parts and products surface coating operations located at major sources of hazardous air pollutants (HAP). The final rule implements section 112(d) of the Clean Air Act (CAA) by requiring these operations to meet HAP emission standards reflecting the application of the maximum achievable control technology (MACT). The final rule will protect air quality and promote the public health by reducing emissions of HAP from facilities in the plastic parts and products surface coating source category. The organic HAP emitted by these operations include methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), toluene, ethylene glycol monobutyl ether (EGBE) and other glycol ethers, and xylenes. Exposure to these substances has been demonstrated to cause adverse health effects such as irritation of the lung, skin, and mucous membranes, and effects on the central nervous system, liver, and heart. In general, these findings have only been shown with concentrations higher than those typically in the ambient air. The final standards are expected to reduce nationwide organic HAP emissions from major sources in this source category by approximately 80 percent.