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On September 1, 1995 (60 FR 45948), EPA promulgated the National Emission Standards for Aerospace Manufacturing and Rework Facilities (40 CFR part 63, subpart GG) under section 112(d) of the Clean Air Act (CAA). The national emission standards for hazardous air pollutants (NESHAP) sets Maximum Achievable Control Technology (MACT) standards for existing and new major sources of hazardous air pollutant emissions and includes standards to control volatile organic compounds (VOC) emissions. Under CAA section 112(d)(6) EPA is required to review standards issued under section 112 and to revise them "as necessary (taking into account developments in practices, processes and control technologies)" no less frequently than every eight years. EPA also must evaluate the MACT standards within eight  years after promulgation and promulgate standards under CAA section 112 (f)(2) if required to provide an ample margin of safety to protect public health or prevent an adverse environmental effect. The source category will be assessed for inhalation risks, including cancer risk and incidence, population cancer risk, and non-cancer effects (chronic and acute). EPA also plans to evaluate multi pathway risk associated with this source category. The agency will follow the Benzene Policy to determine if the source category has low risk, acceptable risk, or unacceptable risk. EPA will then evaluate the effectiveness and cost of additional risk reduction options and make acceptability and ample-margin-of-safety determinations. After assessing the risk from exposure to toxic air emissions from aerospace manufacturing and rework, the EPA has proposed that the emission standards provide an acceptable level of risk with an ample margin of safety to protect public health. Furthermore, the technology assessment did not identify any practices, processes or control technologies that were not already required by the aerospace NESHAP or considered in its development. The EPA also did not identify any improvements to those practices, processes, or control technologies that could be transferred and applied to this source category. However, we have proposed to add standards to limit organic and inorganic HAP emissions from specialty coating application operations and updating the provisions regulating emissions during periods of SSM to ensure the standards are consistent with the requirements of the CAA as interpreted by the courts.