40 CFR § 96.203
Measurements, abbreviations, and acronyms
June 9, 2020
Measurements, abbreviations, and acronyms used in this subpart and subparts BBB through III are defined as follows:
Btu—British thermal unit
CO2—carbon dioxide
H2O—water
Hg—mercury
hr—hour
kW—kilowatt electrical
kWh—kilowatt hour
lb—pound
mmBtu—million Btu
MWe—megawatt electrical
MWh—megawatt hour
NOX—nitrogen oxides
O2—oxygen
ppm—parts per million
scfh—standard cubic feet per hour
SO2—sulfur dioxide
yr—year
[71 FR 25387, Apr. 28, 2006]