GAS ANALYSIS – The determination of the constituents of a gaseous mixture.
GAS BURNER – A burner that uses gas or fuel.
GAS PRESSURE REGULATOR – A spring loaded, dead weighted or pressure balanced device which will maintain the gas pressure to the burner supply line.
GAUGE COCK – A valve attached to a water column or drum for checking water level.
GAUGE GLASS – The transparent part of a water gauge assembly connected directly or through a water column to the boiler, below and above the water line, to indicate the water level in a boiler.
GAUGE PRESSURE – The pressure above atmospheric pressure.
GRADE – Oil classification according to quality, generally based on ASTM specifications.
GRAINS PER CU-FT – The term for expressing dust loading in weight per unit of gas volume (7000 grains equals one pound).
GRAINS (WATER) – A unit of measure commonly used in water analysis for the measurement of impurities in water (17.1 grains = 1 part per million – ppm).
GRAVITY – Weight index of fuels: liquid, petroleum products expressed either as specific, Baume or A.P.I. (American Petroleum Institute) gravity; weight index of gaseous fuels as specific gravity related to air under specified conditions; or weight index of solid fuels as specific gravity related to water under specified conditions.