1. a) The following abbreviations are used in this Part:

   btu	British thermal units (60¼°F)
   dscf	dry standard cubic foot
   ft	foot
   ft2	square feet
   fpm	feet per minute
   gal	gallon
   gr	grains
   gr/scf	grains per standard cubic foot
   gr/dscf	grains per dry standard cubic foot
   hr	hour
   J	Joule
   kg	kilogram
   kg/MW-hr	kilograms per megawatt-hour
   km	kilometer
   L	liter
   lbs	pounds
   lbs/hr	pounds per hour
   lbs/mmbtu	pounds per million btu
   m	meter
   m2	square meters
   mph	miles per hour
   mg	milligram
   mg/scm	milligrams per standard cubic meter
   mg/dscm	milligrams per dry standard cubic meter
   mg/L	milligrams per liter
   Mg	megagram, metric ton or tonne
   mi	mile
   mmbtu	million British thermal units
   mmbtu/hr	million British thermal units per hour
   MW	megawatt; one million watts
   MW-hr	megawatt-hour
   ng	nanogram; one billionth of a gram
   ng/J	nanograms per Joule
   scf	standard cubic foot
   scfm	standard cubic feet per minute
   scm	standard cubic meter
   T	short ton (2000 lbs)
   yd2	square yards

2. b) The following conversion factors have been used in this Part:

   English	Metric
   2.205 lbs	1 kg
   1 T	0.907 Mg
   1 lb/T	0.500 kg/Mg
   mmbtu/hr	0.293 MW
   1 lb/mmbtu	1.548 kg/MW-hr or 430 mg/J
   1 mi	1.61 km
   1 gr	64.81 mg
   1 gr/scf	2289 mg/scm
   1 ft2	0.0929 m2
   1 ft	0.3048 m
   1 gal	3.785 L

(Source: Amended at 20 Ill. Reg. 7605, effective May 22, 1996)