§ 63.12005 What definitions apply to this subpart?

Terms used in this subpart are defined in the Clean Air Act, in § 63.2, and in this section, as follows:

Affirmative defense means, in the context of an enforcement proceeding, a response or defense put forward by a defendant, regarding which the defendant has the burden of proof, and the merits of which are independently and objectively evaluated in a judicial or administrative proceeding.

Batch emission episode means a discrete venting episode that is associated with a single unit operation. A unit operation may have more than one batch emission episode. For example, a displacement of vapor resulting from the charging of a vessel with HAP will result in a discrete emission episode that will last through the duration of the charge and will have an average flowrate equal to the rate of the charge. If the vessel is then heated, there will also be another discrete emission episode resulting from the expulsion of expanded vapor. Both emission episodes may occur in the same vessel or unit operation. There are possibly other emission episodes that may occur from the vessel or other process components, depending on process operations.

Batch operation means a noncontinuous operation involving intermittent or discontinuous feed into process components, and, in general, involves the emptying of the process components after the operation ceases and prior to beginning a new operation. Addition of raw material and withdrawal of product do not occur simultaneously in a batch operation.

Batch process vent means a vent from a batch operation from a PVCPU through which a HAP-containing gas stream has the potential to be released to the atmosphere except that it is required by this subpart to routed to a closed vent system and control device. Emissions for all emission episodes associated with the unit operation(s) are part of the batch process vent. Batch process vents also include vents with intermittent flow from continuous operations. Examples of batch process vents include, but are not limited to, vents on condensers used for product recovery, polymerization reactors, and process tanks.

Bottoms receiver means a tank that collects bottoms from continuous distillation before the stream is sent for storage or for further downstream processing. A rundown tank is an example of a bottoms receiver.

Bulk process means a process for producing polyvinyl chloride resin that is characterized by a two-step anhydrous polymerization process: the formation of small resin particles in a pre-polymerization reactor using small amounts of vinyl chloride monomer, an initiator, and agitation; and the growth of the resin particles in a post-polymerization reactor using additional vinyl chloride monomer. Resins produced using the bulk process are referred to as bulk resins.

Bypass means diverting a process vent or closed vent system stream to the atmosphere such that it does not first pass through an emission control device.

Calendar year means the period between January 1 and December 31, inclusive for a given year.

Capacity means the nominal figure or rating given by the manufacturer of the storage vessel, condenser, or other process component.

Car-seal means a seal that is placed on a device that is used to change the position of a valve (e.g., from opened to closed) in such a way that the position of the valve cannot be changed without breaking the seal.

Closed vent system means a system that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow inducing devices that collect or transport gas or vapor from an emission point to a control device.

Combustion device means an individual unit used for the combustion of organic emissions, such as a flare, incinerator, process heater, or boiler.

Conservation vent means an automatically operated (e.g., weight-loaded or spring-loaded) safety device used to prevent the operating pressure of a storage vessel from exceeding the maximum allowable working pressure of the process component. Conservation vents must be designed to open only when the operating pressure of the storage vessel exceeds the maximum allowable working pressure of the process component. Conservation vents open and close to permit only the intake or outlet relief necessary to keep the storage vessel within permissible working pressures, and reseal automatically.

Container means a portable unit in which a material can be stored, transported, treated, disposed of or otherwise handled. Examples of containers include, but are not limited to, drums, pails, and portable cargo containers known as “portable tanks” or “totes.” Container does not include transport vehicles or barges.

Continuous emission monitoring system (CEMS) means the total equipment that may be required to meet the data acquisition and availability requirements of this subpart, used to sample, condition (if applicable), analyze, and provide a record of emissions.

Continuous operation means any operation that is not a batch operation.

Continuous parameter monitoring system (CPMS) means the total equipment that may be required to meet the data acquisition and availability requirements of this part, used to sample, condition (if applicable), analyze, and provide a record of process or control system parameters.

Continuous process vent means a vent from a continuous PVCPU operation through which a HAP-containing gas stream has the potential to be released to the atmosphere except that it is required by this subpart to routed to a closed vent system and control device and has the following characteristics:

(1) The gas stream originates as a continuous flow from any continuous PVCPU operation during operation of the PVCPU.

(2) The discharge into the closed vent system and control device meets at least one of the following conditions:

(i) Is directly from any continuous operation.

(ii) Is from any continuous operation after passing solely (i.e., without passing through any other unit operation for a process purpose) through one or more recovery devices within the PVCPU.

(iii) Is from a device recovering only mechanical energy from a gas stream that comes either directly from any continuous operation, or from any continuous operation after passing solely (i.e., without passing through any other unit operation for a process purpose) through one or more recovery devices within the PVCPU.

Continuous PVCPU operation means any operation that is not a batch operation or an operation that generates a miscellaneous process vent.

Continuous record means documentation, either in hard copy or computer readable form, of data values measured at least once every 15 minutes and recorded at the frequency specified in § 63.11990(e)(1).