Section 49.4177 - VOC emissions control devices(a)Applicability. The requirements in this section apply to all flares and enclosed combustors used to control VOC emissions at an oil and natural gas source, as identified in § 49.4169(b) , in order to meet the requirements specified in §§ 49.4173 through 49.4176 , as applicable.(b)Exemptions. This section does not apply to VOC emission control devices that are subject to the requirements for control devices used to comply with the emissions standards in 40 CFR part 60, subparts OOOO or OOOOa; or 40 CFR part 63, subpart HH.(c)Enclosed combustors and flares. Each owner or operator must meet the following requirements for enclosed combustors and flares: (1) For each enclosed combustor or flare, the owner or operator must follow the manufacturer's written operating instructions, procedures, and maintenance schedule to ensure good air pollution control practices for minimizing emissions;(2) The owner or operator must ensure that each enclosed combustor or flare is designed to have sufficient capacity to reduce the mass content of VOC in the captured emissions routed to it by at least 95.0 percent for the minimum and maximum natural gas volumetric flow rate and BTU content routed to the device;(3) Each enclosed combustor or flare must be operated to reduce the mass content of VOC in the captured emissions routed to it by continuously meeting at least 95.0 percent VOC control efficiency;(4) The owner or operator must ensure that each flare is designed and operated in accordance with the requirements of 40 CFR 60.18(b) for such flares;(5) The owner or operator must ensure that each enclosed combustor is: (i) A model that is: (A) Demonstrated by a manufacturer to meet the VOC control efficiency requirements of §§ 49.4173 through 49.4176 using EPA-approved performance test procedures specified in 40 CFR 60.5413 ; or(B) Demonstrated by the owner or operator to meet the VOC control efficiency requirements of §§ 49.4173 through 49.4176 according to the procedures and schedule specified in § 49.4182(d)(1) ;(ii) Operated properly at all times that captured emissions are routed to it;(iii) Operated with a liquid knock-out system to collect any condensable vapors (to prevent liquids from going through the control device);(iv) Equipped and operated with a flash-back flame arrestor;(v) Equipped and operated with one of the following:(A) A continuous burning pilot; or(B) An operational electronically controlled automatic ignition device;(vi) Equipped with a monitoring system for continuous measuring and recording of the parameters that indicate proper operation of each enclosed combustor or flare, including each continuous burning pilot flame or electronically controlled automatic ignition device, to monitor and document proper operation of the enclosed combustor or flare. Examples of such continuous monitoring systems may include a thermocouple and a chart recorder, data logger or similar device, or connection to a SCADA system;(vii) Maintained in a leak-free condition; and(viii) Operated with no visible smoke emissions.(d)Other control devices. Upon prior written approval by the EPA, the owner or operator may use control devices other than those listed above that are determined by the EPA to be capable of reducing the mass content of VOC in the natural gas routed to it by at least 95.0 percent, provided that: (1) In operating such control devices, the owner or operator must follow the manufacturer's written operating instructions, procedures and maintenance schedule to ensure good air pollution control practices for minimizing emissions; and(2) The owner or operator must ensure there is sufficient capacity to reduce the mass content of VOC in the produced natural gas and natural gas emissions routed to such other control devices by at least 95.0 percent for the minimum and maximum natural gas volumetric flow rate and BTU content routed to each device.(3) The owner or operator must operate such a control device to reduce the mass content of VOC in the produced natural gas and natural gas emissions routed to it by at least 95.0 percent.