of water = 8.345 pounds (4°C)
1 kilogram = 2.205 pounds
1 gram = 15.43 grains
1 pound = 453.59 grams
1 ounce (avoir.) = 28.35 grams
1 gram mole of a perfect gas 24.45 liters (at 25°C and 760 mm Hg barometric pressure)
1 atmosphere = 14.7 pounds per square inch
1 foot of water pressure = 0.4335 pound per square inch
1 inch of mercury pressure = 0.4912 pound per square inch
1 dyne per square centimeter = 0.0021 pound per square foot
1 gram‐calorie = 0.00397 Btu
1 Btu = 778 foot‐pounds
1 Btu per minute = 12.96 foot‐pounds per second
1 hp = 0.707 Btu per second = 550 foot‐pounds per second
1 centimeter per second = 1.97 feet per minute = 0.0224 mile per hour
1 footcandle = 1 lumen incident per square foot = 10.764 lumens incident per square meter
1 grain per cubic foot = 2.29 grams per cubic meter
1 milligram per cubic meter = 0.000437 grain per cubic foot
To convert degrees Celsius to degrees Fahrenheit: °C (9/5) + 32 = °F
To convert degrees Fahrenheit to degrees Celsius: (5/9) (°F − 32) = °C
For solutes in water: 1 mg/liter 1 ppm (by weight)
Atmospheric contamination: 1 mg/liter 1 oz/1000 cu ft (approx)
For gases or vapors in air at 25°C and 760 mm Hg pressure:
To convert mg/liter to ppm (by volume): mg/liter (24,450/mol. wt.) = ppm
To convert ppm to mg/liter: ppm (mol. wt./24,450) = mg/liter
Factors for conversion of some units
Mg/L × 28.32 = Mg/cubic foot
Mg/L × 1000 = Mg /cubic meter
Mg/cubic foot × 35.314 = Mg/cubic meter
Mg/cubic meter × 0.2832 = Mg/cubic foot
CONVERSION TABLE FOR GASES AND VAPORSa (Milligrams per liter to parts per million, and vice versa; 25°C and 760 mm Hg barometric pressure)
Molecular Weight | 1 mg/liter ppm | 1 ppm mg/liter | Molecular Weight | 1 mg/liter ppm | 1 ppm mg/liter | Molecular Weight | 1 mg/liter ppm | 1 ppm mg/liter |
1 | 24,450 | 0.0000409 | 39 | 627 | 0.001595 | 77 | 318 | 0.00315 |
2 | 12,230 | 0.0000818 | 40 | 611 | 0.001636 | 78 | 313 | 0.00319 |
3 | 8,150 | 0.0001227 | 41 | 596 | 0.001677 | 79 | 309 | 0.00323 |
4 | 6,113 | 0.0001636 | 42 | 582 | 0.001718 | 80 | 306 | 0.00327 |
5 | 4,890 | 0.0002045 | 43 | 569 | 0.001759 | 81 | 302 | 0.00331 |
6 | 4,075 | 0.0002454 | 44 | 556 | 0.001800 | 82 | 298 | 0.00335 |
7 | 3,493 | 0.0002863 | 45 | 543 | 0.001840 | 83 | 295 | 0.00339 |
8 | 3,056 | 0.000327 | 46 | 532 | 0.001881 | 84 | 291 | 0.00344 |
9 | 2,717 | 0.000368 | 47 | 520 | 0.001922 | 85 | 288 | 0.00348 |
10 | 2,445 | 0.000409 | 48 | 509 | 0.001963 | 86 | 284 | 0.00352 |
11 | 2,223 | 0.000450 | 49 | 499 | 0.002004 | 87 | 281 | 0.00356 |
12 | 2,038 | 0.000491 | 50 | 489 | 0.002045 | 88 | 278 | 0.00360 |
13 | 1,881 | 0.000532 | 51 | 479 | 0.002086 | 89 | 275 | 0.00364 |
14 | 1,746 | 0.000573 | 52 | 470 | 0.002127 | 90 | 272 | 0.00368 |
15 | 1,630 | 0.000614 | 53 | 461 | 0.002168 | 91 | 269 | 0.00372 |
16 | 1,528 | 0.000654 | 54 | 453 | 0.002209 |