clear height , in relation to a sign, means the vertical distance between the lowest edge of the sign and the natural level of the surrounding ground, footway or roadway immediately below the sign.
height means the vertical distance between grade and the highest point of the building or structure;
Watertight in relation to a structure means capable of preventing the passage of water through the structure in any direction under a head of water for which the surrounding structure is designed;
Sign height means the vertical distance from the ground directly below the sign measured to the highest extremity of the sign, including the sign structure;
Heat input means the product (expressed in mmBtu/time) of the gross calorific value of the fuel (expressed in Btu/lb) and the fuel feed rate into the combustion device (expressed in mass of fuel/time) and does not include the heat derived from preheated combustion air, recirculated flue gases, or ex- haust from other sources.