§ 51.50 What definitions apply to this subpart?

Aircraft engine type means a code defining a unique combination of aircraft and engine used as an input parameter for calculating emissions from aircraft.

Annual emissions means actual emissions for a plant, point, or process that are measured or calculated to represent a calendar year.

Control measure means a unique code for the type of control device or operational measure (e.g., wet scrubber, flaring, process change, ban) used to reduce emissions.

Emission calculation method means the code describing how the emissions for a pollutant were calculated, e.g., by stack test, continuous emissions monitor, EPA emission factor, etc.

Emission factor means the ratio relating emissions of a specific pollutant to an activity throughput level.

Emission operating type means the operational status of an emissions unit for the time period for which emissions are being reported, i.e., Routine, Startup, Shutdown, or Upset.

Emission process identifier means a unique code for the process generating the emissions.

Emission type means the type of emissions produced for onroad and nonroad sources or the mode of operation for marine vessels.

Emissions year means the calendar year for which the emissions estimates are reported.

Facility site identifier means the unique code for a plant or facility treated as a point source, containing one or more pollutant-emitting units. The EPA's reporting format allows for state submittals to use either the state's data system identifiers or the EPA's Emission Inventory System identifiers.

Facility site name means the name of the facility.

Lead (Pb) means lead as defined in 40 CFR 50.12. Emissions of Pb which occur either as elemental Pb or as a chemical compound containing Pb should be reported as the mass of the Pb atoms only.

Mobile source means a motor vehicle, nonroad engine or nonroad vehicle, where: