(a) The provisions of §§115.162 - 115.167 of this title (relating to Control Requirements; Alternate Control Requirements; Determination of Emissions and Flow Rates; Approved Test Methods and Testing Requirements; Monitoring and Recordkeeping Requirements; and Exemptions) apply to vent gas streams at batch process operations in the Beaumont-Port Arthur, Bexar County, and Houston-Galveston-Brazoria areas, as defined in §115.10 of this title (relating to Definitions), under the following Standard Industrial Classification (SIC) codes:(1) 2821 (plastic resins and materials);(2) 2833 (medicinals and botanicals);(3) 2834 (pharmaceutical preparations);(4) 2861 (gum and wood chemicals);(5) 2865 (cyclic crudes and intermediates);(6) 2869 (industrial organic chemicals, not elsewhere classified); and(7) 2879 (agricultural chemicals, not elsewhere classified).(b) Any batch process operation that is exempt under §115.167(1) or (2)(A) of this title is subject to the requirements of Division 2 of this subchapter (relating to Vent Gas Control).(c) Any batch process in the Houston-Galveston-Brazoria area in which a highly-reactive volatile organic compound, as defined in §115.10 of this title, is a raw material, intermediate, final product, or in a waste stream is subject to the requirements of Subchapter H of this chapter (relating to Highly-Reactive Volatile Organic Compounds) in addition to the applicable requirements of either this division (relating to Batch Processes) or Division 2 of this subchapter, whichever of these two divisions applies.