Definitions. The definitions in § 721.3 apply to this section. In addition, the following definitions apply:
Flow meter means an instrument used in various applications to measure the flow rate of liquids or gases.
Hygrometer means an instrument used in various applications to measure humidity of gases.
Manometer means an instrument used in various applications to measure pressure of gases or liquids.
Motor vehicle has the meaning found at 40 CFR 85.1703 .
Natural gas manometer means an instrument used in the natural gas industry to measure gas pressure.
Psychrometer means an instrument used in various applications to measure humidity of gases.
Pyrometer means an instrument used in various applications to measure extremely high temperatures.
40 C.F.R. §721.10068