Introduction - Mathematics and Statistics for the Environment - page 12

TABLE 1.3 (continued)
Conversion Factors by Unit Category

Factor Metric (SI) or English Conversions

1 bar 0.987 atm (atmospheres)

1 × 10 6 dynes/cm 2 (dynes/square centimeter)
33.45 ft of H 2 O (feet of water)
1 × 10 5 Pa (pascals)
750.06 torr
750.06 mmHg (millimeters of mercury)

1 inch of water 1.86 mmHg (millimeters of mercury)

249.09 Pa (pascals)
0.0361 psi (lb/in. 2 )

1 mmHg (millimeter of
mercury)

1.316 × 10 -3 atm (atmospheres)
0.535 in H 2 O (inches of water)
1.33 mb (millibars)
133.32 Pa (pascals)
1 torr
0.0193 psia (pounds per square inch absolute)

1 pascal 9.87 × 10 -6 atm (atmospheres)

4.015 × 10 -3 in H 2 O (inches of water)
0.01 mb (millibars)
7.5 × 10 -3 mmHg (millimeters of mercury)

1 psi (pounds per square inch) 0.068 atm (atmospheres)

27.67 in H 2 O (inches of water)
68.85 mb (millibars)
51.71 mmHg (millimeters of mercury)
6,894.76 Pa (pascals)

1 torr 1.33 mb (millibars)

Units of Velocity or Speed

1 fps (feet per second) 1.097 kmph (kilometers/hour)

0.305 mps (meters/second)
0.01136 mph (miles/hours)

1 mps (meters per second) 196.9 fpm (feet/minute)

3.6 kmph (kilometers/hour)
2.237 mph (miles/hour)

1 mph (miles per hour) 88 fpm (feet/minute)

1.61 kmph (kilometers/hour)
0.447 mps (meters/second)
Units of Density

1 g/cm 3 (grams per cubic
centimeter)

62.43 lb/ft 3 (pounds/cubic foot)
0.0361 lb/in. 3 (pounds/cubic inch)
8.345 lb/gal (pounds/gallon)

1 lb/ft 3 (pounds/cubic foot) 16.02 g/L (grams/liter)

1 lb/in 2 (pounds/cubic inch) 27.68 g/cm 3 (grams/cubic centimeter)

1.728 lb/ft 3 (pounds/cubic foot)
Units of Concentration

1 ppm (parts/million-volume) 1.00 mL/m 3 (milliliters/cubic meter)

1 ppm (wt) 1.00 mg/kg (milligrams/kilograms)