Measurements, abbreviations, and acronyms.

Measurements, abbreviations, and acronyms used in this subpart and subparts BBBB through IIII are defined as follows: Btu—British thermal unit. CO 2 —carbon dioxide. H 2 O—water. Hg—mercury. hr—hour. kW—kilowatt electrical. kWh—kilowatt hour. lb—pound. mmBtu—million Btu. MWe—megawatt electrical. MWh—megawatt hour. NO X —nitrogen oxides. O 2 —oxygen. ppm—parts per million. scfh—standard cubic feet per hour. SO 2 —sulfur dioxide. yr—year.