Conversion Factors

C-1 Copyright © 2007 Water Environment Federation. C-2 Operation of Municipal Wastewater Treatment Plants s и 3 h s s 3 2 s s и и и 3 3 и и 2 3 3 2 s /m /L /s /m /s и 2 3 3 3 3 3 3 m Pa m m L/s m m L/m 3 3 6 3 5 2 3 Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ 4 10 10 10 10 10 10 10 Ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ 304.8 L/m 4.1864.182 J J 0.404 7 ha (hectare) 0.278 7 kJ/L 7.482 7.867 0.471 9 L/s 15°C 20°C cubic feet per minute thousand cfm/1000 cu ft 1.667 British thermal units per poundBritish thermal units per toncalorie internationalcalories per secondcentipoise Btu/lb Btu/ton cal 2.326 1.163 cal/sec kJ/kg J/kg cP 4.187 4.187 J (joule) W 1.000 cubic feet per million gallonscubic feet per minute thousand gallons cfm/1000 gal cu ft/mil. gal 0.124 7 7.482 L/m mL/m acre-footBritish thermal units per hourBritish thermal units per hour square foot Btu/hr/sq ft 3.155 Btu/hr ac-ft J/m 0.2931 1233cubic feet per minute foot W (watt) m cfm/ft 1.549 L/m cubic feet per galloncubic feet per hour square foot cfh/sq ft cu ft/gal 8.467 7.482 m Table 1. Conversion from customary to metric units (in alphabetical order). Multiply Customary UnitacreatmospherebarBritish thermal unitBritish thermal units per cubic footBritish thermal units per gallon Abbreviation By Btu/cu ft Btu/gal Btu ac 37.26 atm To Obtain Metric Unit 278.7 bar kJ/m cubic feet per minute 1.055 101.3 4.047 kJ/m 100.0 kJ (kilojoule) kPa (kilopascal) kPa cfm or cu ft/min 4.719 10 cubic feet per hour cfh or cu ft/hr 7.867

Copyright © 2007 Water Environment Federation. Conversion Factors C-3 s s s и и и d s и 2 2 2 s s d и и и и 2 2 /kg /s /m /m /d /m m 3 3 3 3 3 3 3 3 3 3 и m m m m m m m/s W m L/s m m L/m 32) °C (degrees Celsius) 2 2 6 8 2 6 5 2 3 5 3 11 8 Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ 10 10 10 10 10 10 10 10 10 10 10 10 10 ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ 69.970.109 3 L/ha L/ha 1.083 28.32 L/s 9.353 L/ha 28.3216.39 L mL 0.304 8 m/s 3.7853.785 L 2 Rankine °R 0.555 6 (Kelvin) K cubic feet per second square milecubic foot cfs/sq mile 1.093 cu ft 2.832 foot-pounds per inchfoot-pounds per minute ft-lb/min ft-lb/in. 2.259 53.38 J/m cubic feet per second acre cfs/ac 6.997 gallons per day capita gpd/cap 3.785 L/cap cubic inchcubic yard cu in. cu ydgallons per day 16.39 0.764 6 m gpd 4.381 feet per minutefeet per secondfeet per second squaredfoot-pounds per secondgallon ft/sec ft/min or fpm ft/sec or fps 5.080 0.304 8 ft-lb/sec mm/s m/s 1.355 gal W 3.785 feet of headfeet per hour ft ft/hr 8.467 0.304 8 m cubic feet per pounddegrees Fahrenheit cu ft/lb 6.243 feet per yearfootfoot-headfoot-pound °F 0.555 6(°F ft/yr ft-head ft-lb ft 0.304 8 2989 1.356 m/a (meters per annum) 0.304 8 Pa N m cubic feet per second cfs 2.832 gallons per day acre gpd/ac 1.083

Copyright © 2007 Water Environment Federation. C-4 Operation of Municipal Wastewater Treatment Plants s)/m h)/m d)/m d)/m s or m/s d or m/d d d и и и и и и и s d s s и 3 d d s s и и и и 2 2 2 s s и и и и s s и и и 2 2 3 2 и /m /m /m /m /m /s /s /d /m /m 3 3 3 3 3 3 3 3 3 3 m L/m m (mL/m m m m L/m m m L/s m m/m . ) 7 4 2 11 7 2 2 6 5 2 4 4 Ϫ Ϫ Ϫ 4 Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ Ϫ 10 10 10 10 10 10 10 10 10 10 10 10 10 continued ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ϫ ( 1.437 2.352 mL/m 0.207 0 L/m 0.679 1 L/m 4.074 40.74 L/m 1.0516.308 mL/s 58.67 m 5.451 m 1.242 er per thousand feet gph/in. dia/1000 ft 488.9 (mL/m per foot-head gallons per minute square foot gpm/sq ft 6.791 gallons per day square foot gpd/sq ft 4.715 gallons per hour foot of diameter foot-headgallons per hour inch diamet gph/ft dia/ft-headgallons per million 11.32 (mL/m gal/mil. gal 1.000 mL/m gallons per day thousand square feetgallons per hour gpd/1000 sq ft 4.074 gallons per minute foot gph gpm/ft 1.051 2.070 gallons per day foot of manhole diameter gpd/ft/ft-head 4.074 gallons per day inch of diameter milegallons per day mile gpd/in. dia/mile 92.60 (mL/m gpd/mile 2.720 gallons per poundgallons per tongrain gal/lb gal/ton 8344 gr 4.173 mL/kg mL/kg 64.80 mg Table 1. Conversion from customary to metric units (in alphabetical order) Multiply Customary Unitgallons per day linear foot gpd/ft Abbreviation By 1.437 gallons per minute To Obtain Metric Unit gpm 6.308 gallons per minute acre gpm/ac 0.155 8 L/ha gallons per minute cubic foot gpm/cu ft 2.228 L/m

Copyright © 2007 Water Environment Federation. grains per gallon gr/gal 17.12 g/m3 17.12 mg/L hectare ha 1.000 ϫ 104 m2 horsepower hp 0.745 7 kW horsepower-hour hp-hr 2.685 MJ horsepower-hours per pound hp-hr/lb 5.919 MJ/kg horsepower-hours per thousand cubic feet hp-hr/1000 cu ft 26.34 W/m3 horsepower-hours per thousand gallons hp-hr/1000 gal 0.710 3 kJ/L horsepower-hours per thousand pounds hp-hr/1000 lb 5.919 kJ/kg Copyright ©2007WaterEnvironment Federation. horsepower per gallon per minute hp/gpm 11.82 MJ/m3 11.82 kJ/L horsepower per million gallons hp/mil. gal 0.197 W/m3 Ϫ 1.970 ϫ 10 4 W/L horsepower per thousand gallons hp/1000 gal 0.197 kW/m3 inch in. 25.40 mm inches of water in. H2O 0.248 8 kPa inches of mercury in. Hg 3.377 kPa inches per foot in./ft 8.333 % inches per hour in./hr 25.40 mm/h inches per year in./yr 25.40 mm/a (millimeters per annum) kilowatt-hour kWh 3.600 MJ kilowatt-hours per day kWh/d 41.67 W kilowatt-hours per gallon kWh/gal 951.1 MJ/m3 0.951 1 MJ/L kilowatt-hours per million gallons kWh/mil. gal 951.1 J/m3 0.951 1 J/L

kilowatt-hours per pound kWh/lb 7.936 MJ/kg C-5 Conversion Factors kilowatt-hours per thousand pounds kWh/1000 lb 7.936 kJ/kg kilowatt-hours per ton kWh/ton 3.969 kJ/kg kip kip 4.448 kN (kilonewton) kip-feet kip-ft 1.356 kNиm kip-feet per second kip-ft/sec 1.356 kNиm/s kips per foot kip/ft 14.59 kN/m kips per square foot kip/sq ft 47.88 kPa - OperationofMunicipalWastewaterTreatmentPlants C-6

Table 1. Conversion from customary to metric units (in alphabetical order) (continued).

Multiply Customary Unit Abbreviation By To Obtain Metric Unit micron ␮ 1.000 ␮m mil mil 25.40 ␮m mile mile 1.609 km miles per hour mph 0.446 9 m/s 1.609 km/h million gallons mil. gal 3.785 ϫ 103 m3 Copyright ©2007WaterEnvironment Federation. 3.785 ML Ϫ million gallons per day mgd 4.383 ϫ 10 2 m3/s 43.83 L/s 3.785 ϫ 103 m3/d 3.785 ML/d Ϫ million gallons per day per acre mgd/ac 1.083 ϫ 10 5 m3/m2иs 9.353 ϫ 103 m3/haиd 9.353 ML/haиd most probable number per hundred milliliters MPN/100 mL 10.00 MPN/L parts per billion ppb 1.00 (app.) ␮g/L 1.000 ␮g/kg parts per million ppm 1.00 (app.) mg/L 1.000 mg/kg pound (force) lbf 4.448 N pound (mass) lb 0.453 6 kg pound-foot lb-ft 1.356 Nиm pound-feet per second lb-ft/sec 1.356 Nиm/s pounds per day per capita lb/d/cap 0.453 6 kg/capиd pounds per cubic foot lb/cu ft 16.02 kg/m3 pounds per thousand cubic feet lb/1000 cu ft 16.02 g/m3 pounds per cubic yard lb/cu yd 0.593 3 kg/m3 pounds per day lb/d 5.250 mg/s 0.453 6 kg/d pounds per day per acre lb/d/ac 0.112 1 g/m2иd pounds per day per acre-foot lb/d/ac-ft 0.367 7 g/m3иd pounds per day per cubic foot lb/d/cu ft 16.02 kg/m3иd pounds per day per pound lb/d/lb 11.57 mg/kgиs pounds per day per square foot lb/d/sq ft 56.51 mg/m2иs 4.882 kg/m2иd Ϫ pounds per day per thousand cubic feet lb/d/1000 cu ft 1.602 ϫ 10 2 kg/m3иd pounds per day per thousand square feet lb/d/1000 sq ft 4.882 g/m2иd pounds per foot lb/ft 1.488 kg/m Copyright ©2007WaterEnvironment Federation. pounds per foot per foot of diameter lb/ft/ft dia 47.88 (N/m)/m pounds per gallon lb/gal 0.119 8 kg/L Ϫ pounds per hour lb/hr 1.260 ϫ 10 4 kg/s 0.453 6 kg/h pounds per hour per square foot lb/hr/sq ft 4.882 kg/m2иh 1.356 g/m2иs Ϫ pounds per hour per cubic foot lb/hr/cu ft 4.450 ϫ 10 6 kg/Lиs 16.02 kg/m3иh pounds per million gallons lb/mil. gal 0.119 8 g/m3 0.119 8 mg/L pounds per pound lb/lb 1000 g/kg pounds per square foot (mass dose) lb/sq ft 4.883 kg/m2 pounds per square foot (force) lb/sq ft 47.88 Pa pounds per square inch (force) psi 6895 Pa pounds per thousand cubic feet lb/1000 cu ft 16.02 g/m3 pounds per thousand gallons lb/1000 gal 0.119 8 g/m3 pounds per ton lb/ton 0.500 g/kg

pounds per year per acre lb/yr/ac 1.121 kg/haиa C-7 Conversion Factors pounds per year per cubic foot lb/yr/cu ft 16.02 kg/m3иa pounds per year per square foot lb/yr/sq ft 4.882 kg/m2иa pound-seconds per square foot lb-sec/sq ft 47.88 Paиs pound-square feet per second lb-sq ft/sec 4.883 kgиm2/s revolutions per minute rpm 1.000 r/min revolutions per second rps 1.000 r/s slug slug 14.59 kg - OperationofMunicipalWastewaterTreatmentPlants C-8

Table 1. Conversion from customary to metric units (in alphabetical order) (continued).

Multiply Customary Unit Abbreviation By To Obtain Metric Unit Copyright ©2007WaterEnvironment Federation. Ϫ square foot sq ft 9.290 ϫ 10 2 m2 Ϫ square feet per capita sq ft/cap 9.290 ϫ 10 2 m2/cap square feet per cubic foot sq ft/cu ft 3.281 m2/m3 square feet per foot sq ft/ft 0.304 8 m2/m Ϫ square feet per second sq ft/sec 9.290 ϫ 10 2 m2/s square inch sq in. 645.2 mm2 square mile sq mile 2.590 km2 square yard sq yd 0.836 1 m2 ton (long) ton 1.016 Mg ton (short) ton 0.907 2 Mg 907.2 kg tons per acre ton/ac 0.224 2 kg/m2 2.242 Mg/ha tons per cubic yard ton/cu yd 1.187 Mg/m3 watt-hour W-hr 3.600 J watts per square foot W/sq ft 10.76 W/m2 yard yd 0.914 4 m Table 2. Conversion from metric to customary units (in alphabetical order) (continued).

Multiply Metric Unit Abbreviation By To Obtain Customary Unit capita per hectare cap/ha 0.404 7 cap/ac capita per square kilometer cap/km2 2.590 cap/sq mile Ϫ cubic meter m3 8.107 ϫ 10 4 ac-ft 6.290 barrel (oil) 8.386 barrel (water) 28.38 bushel (U.S. dry) Copyright ©2007WaterEnvironment Federation. 35.31 cu ft 1.308 cu yd 264.2 gal Ϫ 2.642 ϫ 10 4 mil. gal cubic meters per cubic meter m3/m3 0.133 7 cu ft/gal 1.337 ϫ 105 cu ft/mil. gal cubic meters per cubic meter per second m3/m3иs 5.999 ϫ 104 cfm/1000 cu ft 8.019 ϫ 103 cfm/1000 gal cubic meters per day m3/d 0.183 5 gpm Ϫ 2.642 ϫ 10 4 mgd 264.2 gpd cubic meters per hectare per day m3/haиd 106.9 gpd/ac Ϫ 1.069 ϫ 10 4 mgd/ac cubic meters per hectare per second m3/haиs 14.29 cfs/ac 9.147 ϫ 103 cfs/sq mile cubic meters per kilogram m3/kg 16.02 cu ft/lb cubic meters per meter per day m3/mиd 80.53 gpd/ft cubic meters per meter per second m3/mиs 646.0 cfm/ft C-9 Conversion Factors 6.959 ϫ 106 gpd/ft 3.676 ϫ 1010 gpd/mile -0OperationofMunicipalWastewaterTreatmentPlants C-10

Table 2. Conversion from metric to customary units (in alphabetical order) (continued).

Multiply Metric Unit Abbreviation By To Obtain Customary Unit cubic meters per second m3/s 1.271 ϫ 105 cfh or cu ft/hr 2.119 ϫ 103 cfm 35.32 cfs 9.515 ϫ 105 gph 1.585 ϫ 104 gpm 22.83 mgd Copyright ©2007WaterEnvironment Federation. cubic meters per square meter per day m3/m2иd 24.55 gpd/sq ft Ϫ 1.704 ϫ 10 2 gpm/sq ft cubic meters per square meter per hour m3/m2иh 3.281 cfh/sq ft cubic meters per square meter per second m3/m2иs 1.429 ϫ 103 cfs/ac 9.149 ϫ 107 cfs/sq mile 9.238 ϫ 1010 gpd/ac 2.121 ϫ 106 gpd/sq ft 1.473 ϫ 103 gpm/sq ft 9.238 ϫ 104 mgd/ac 1.181 ϫ 104 cfh/sq ft Ϫ cubic millimeter mm3 6.102 ϫ 10 5 cu in. degrees Celsius °C 1.800 (°C)ϩ 32 °F Kelvin K 1.800 °R grams per cubic meter g/m3 8.344 lb/mil.gal Ϫ 6.243 ϫ 10 2 lb/1000 cu ft 8.347 lb/1000 gal grams per cubic meter per day g/m3иd 2.720 lb/d/ac-ft grams per cubic meter per second g/m3иs 0.224 7 lb/hr/cu ft Ϫ grams per kilogram g/kg 1.000 ϫ 10 3 lb/lb 2.000 lb/ton grams per liter g/L 0.0624 lb/cu ft grams per meter g/m 0.672 0 lb/1000 ft grams per second g/s 7.937 lb/hr grams per square meter per day g/m2иd 8.922 lb/d/ac 0.204 8 lb/d/1000 sq ft grams per square meter per second g/m2иs 17.70 lb/d/sq ft 0.737 3 lb/hr/sq ft hectare ha 2.471 ac (acre) joule J 0.7376 ft-lb Ϫ joules per cubic meter J/m3 1.051 ϫ 10 3 kWh/mil. gal Ϫ joules per kilogram J/kg 4.299 ϫ 10 4 Btu/lb 0.859 8 Btu/ton Ϫ 1.689 ϫ 10 4 hp-hr/1000 lb Ϫ joules per liter J/L 8.461 ϫ 10 5 hp/gpm Copyright ©2007WaterEnvironment Federation. 1.051 kWh/mil. gal Ϫ joules per meter J/m 1.873 ϫ 10 2 ft-lb/in. joules per square meter per second J/m2иs 0.317 1 Btu/hr/sq ft kilogram kg 2.205 lb (mass) Ϫ 1.102 ϫ 10 3 ton Ϫ 6.854 ϫ 10 2 slug kilogram meter kgиm 0.672 0 lb-ft kilogram meter per second kgиm/s 0.672 0 lb-ft/sec kilograms per capita per day kg/capиd 2.205 lb/cap/d Ϫ kilograms per cubic meter kg/m3 6.243 ϫ 10 2 lb/cu ft 1.686 lb/cu yd 834 7 lb/mil. gal 62.42 lb/1000 cu ft Ϫ kilograms per cubic meter per day kg/m3иd 6.242 ϫ 10 2 lb/cu ft 62.42 lb/d/1000 cu ft Ϫ kilograms per cubic meter per hour kg/m3иh 6.242 ϫ 10 2 lb/hr/cu ft kilograms per cubic meter per second kg/m3иs 224.8 lb/hr/cu ft

kilograms per day kg/d 2.205 lb/d C-11 Conversion Factors kilograms per hectare per day kg/haиd 0.892 2 lb/d/ac kilograms per hectare per year (annum) kg/haиa 0.892 2 lb/yr/ac kilograms per hour kg/h 2.205 lb/hr kilograms per kilogram per second kg/kgиs 8.64 ϫ 104 lb/d/lb Ϫ kilograms per liter kg/L 3.613 ϫ 10 2 lb/cu in. 8.347 lb/gal 8.347 ϫ 106 lb/mil. gal -2OperationofMunicipalWastewaterTreatmentPlants C-12

Table 2. Conversion from metric to customary units (in alphabetical order) (continued).

Multiply Metric Unit Abbreviation By To Obtain Customary Unit kilograms per meter kg/m 0.672 0 lb/ft kilograms per second kg/s 1.905 ϫ 105 lb/d 7.936 ϫ 103 lb/hr kilograms per square meter kg/m2 0.204 8 lb/sq ft (mass dose) kilograms per square meter per day kg/m2иd 0.204 8 lb/d/sq ft kilograms per square meter per hour kg/m2иh 0.204 8 lb/hr/sq ft Copyright ©2007WaterEnvironment Federation. kilograms per square meter per second kg/m2иs 1.770 ϫ 104 lb/d/sq ft kilograms per square meter per year (annum) kg/m2иa 0.204 8 lb/yr/sq ft kilojoule kJ 0.947 8 Btu Ϫ kilojoules per cubic meter kJ/m3 2.684 ϫ 10 2 Btu/cu ft 1.051 kWh/mil. gal Ϫ 1.408 ϫ 10 3 hp-hr/1000 gal kilojoules per kilogram kJ/kg 0.430 0 Btu/lb 859.8 Btu/ton 0.252 0 kWh/ton 0.126 0 kWh/1000 1b Ϫ 1.689 ϫ 10 4 hp-hr/lb kilojoules per liter kJ/L 1.410 Btu/gal kilometer km 0.621 4 mile kilometers per hour km/h 0.621 4 mph kilonewton kN 0.224 8 kip kilonewton per meter kN/m 0.737 5 kip-ft kilonewtons per meter per second kN/mиs 0.737 5 kip-ft/sec Ϫ kilopascal kPa 9.872 ϫ 10 3 atm 20.89 psf (force) 0.145 0 psi (force) 4.019 in. H2O 0.296 1 in. Hg kilowatt kW 1.341 hp kilowatt per cubic meter kW/m3 5.076 hp/1000 gal Ϫ liter L 3.532 ϫ 10 2 cu ft 0.264 2 gal Ϫ liters per capita L/cap 3.532 ϫ 10 2 cu ft/cap liters per capita per day L/capиd 0.264 2 gpd/cap liters per cubic meter L/m3 133.7 cu ft/mil. gal liters per cubic meter per second L/m3иs 0.488 8 cfm/cu ft 59.99 cfm/1000 cu ft 8.019 cfm/1000 gal Ϫ liters per hectare per second L/haиs 1.429 ϫ 10 2 cfs/ac 9.149 cfs/sq mile 6.418 gpm/ac Copyright ©2007WaterEnvironment Federation. liters per kilogram L/kg 239.6 gal/ton liters per meter L/m 425.2 gal/mile liters per meter per second L/mиs 0.645 9 cfm/ft 4.832 gpm/ft 6.958 ϫ 103 gpd/ft liters per second L/s 127.1 cfh 2.119 cfm Ϫ 3.532 ϫ 10 2 cfs 2.282 ϫ 104 gpd 15.85 gpm Ϫ 2.283 ϫ 10 2 mgd Ϫ liters per square meter per day L/m2иd 2.455 ϫ 10 2 gpd/sq ft liters per square meter per second L/m2иs 11.82 cfh/sq ft 2.121 ϫ 103 gpd/sq ft Ϫ 9.237 ϫ 10 3 gpd/ac 1.473 gpm/sq ft megagram or metric ton Mg or t 1.102 ton (short)

0.984 3 ton (long) C-13 Conversion Factors megagram per cubic meter Mg/m3 0.842 5 ton/cu yd megagram per hectare Mg/ha 0.446 0 ton/ac megajoule MJ 0.372 5 hp-hr Ϫ megajoules per cubic meter MJ/m3 8.460 ϫ 10 2 hp/gpm Ϫ 1.051 ϫ 10 3 kWh/gal megajoules per kilogram MJ/kg 168.9 hp-hr/1000 lb 0.126 0 kWh/lb -4OperationofMunicipalWastewaterTreatmentPlants C-14

Table 2. Conversion from metric to customary units (in alphabetical order) (continued).

Multiply Metric Unit Abbreviation By To Obtain Customary Unit megajoules per liter MJ/L 1.051 kWh/gal Copyright ©2007WaterEnvironment Federation. megaliter ML 0.264 2 mil. gal megaliters per day ML/d 0.264 2 mgd megaliters per hectare per day ML/haиd 0.106 9 mgd/ac meter m 3.281 ft meters per hour m/h 3.281 ft/hr meters per second m/s 3.281 fps 2.238 mph meters per second squared m/s2 3.281 ft/sec2 micrograms per liter ␮g/L 1.00 (app.) ppb micrometer ␮m 1.000 micron Ϫ 3.937 ϫ 10 2 mil Ϫ miligram mg 1.543 ϫ 10 2 grain Ϫ milligrams per liter mg/L 5.841 ϫ 10 2 grains per gallon 1.00 (app.) ppm Ϫ milliliter mL 6.102 ϫ 10 2 cu in. milliliters per cubic meter mL/m3 0.133 7 cu ft/mil. gal Ϫ milliliters per kilogram mL/kg 1.198 ϫ 10 4 gal/lb 0.239 6 gal/ton Ϫ milliliters per meter per day per meter (mL/mиd)/m 2.450 ϫ 10 3 gpd/ft/ft-head milliliters per second mL/s 0.951 5 gph Ϫ millimeter mm 3.937 ϫ 10 2 in. Ϫ millimeters per hour mm/h 3.937 ϫ 10 2 in./hr millimeters per second mm/s 0.196 9 fpm 11.81 ft/hr Ϫ most probable number per cubic meter MPN/m3 1.000 ϫ 10 4 MPN/100 mL most probable number per liter MPN/L 0.100 0 MPN/100 mL newton N 0.224 8 lbf (force) newton meter Nиm 0.737 6 ft-lb newton meters per meter Nиm/m 0.224 8 lb-ft/ft dia Ϫ pascal Pa 9.872 ϫ 10 6 atm Ϫ 3.345 ϫ 10 4 ft (head) Ϫ 2.089 ϫ 10 2 lb/sq ft Ϫ 1.450 ϫ 10 4 psi Ϫ pascal second Paиs 2.089 ϫ 10 2 lb-sec/sq ft square kilometer km2 0.386 1 sq mile Ϫ Copyright ©2007WaterEnvironment Federation. square meter m2 2.471 ϫ 10 4 ac 10.76 sq ft square meters per cubic meter m2/m3 3.048 sq ft/cu ft square meters per meter m2/m 3.281 sq ft/ft square meter per second m2/s 10.76 sq ft/sec Ϫ square millimeter mm2 1.550 ϫ 10 3 sq in. Ϫ ton (metric) t 1.102 ϫ 10 3 lb 0.984 3 ton (long) 1.102 ton (short) watt W 3.412 Btu/hr 947.8 Btu/sec 44.27 ft-lb/min 0.738 0 ft-lb/sec Ϫ 1.341 ϫ 10 3 hp Ϫ 2.400 ϫ 10 2 kWh/d watts per cubic meter W/m3 5.076 hp/mil. gal Ϫ 3.797 ϫ 10 2 hp/1000 cu ft ϫ 3 watts per liter W/L 5.076 10 hp/mil. gal C-15 Conversion Factors Ϫ watts per square meter W/m2 9.290 ϫ 10 2 W/sq ft