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METRIC CONVERSION LINKS

Following are several excellent web sites with conversion factors, tables,
and conversion calculators:

ConvertMe.com:
      http://www.convert-me.com/en/

Engineering Network: Metric Conversion Chart:
      http://www.engnetglobal.com/tips/convert.asp

Freie Universitat Berlin: Insitut fur Chemie und Biochemie: Conversion of Units:
      http://www.chemie.fu-berlin.de/chemistry/general/units_en.html

Mack Corporation: Engineering Conversion Factors:
      http://www.mackcorp.com/engineeringconversionfactors/convfactors.html

NASA: Units of Measure & Conversion Factors:
      http://msis.jsc.nasa.gov/volume2/Appx_e_units.htm#M

On-Line Conversions.com:
      http://www.onlineconversion.com/

Science Made Easy:
      http://www.sciencemadesimple.com/conversions.html

Wikipedia Encyclopedia: Conversion Units
      http://en.wikipedia.org/wiki/Conversion_of_units

METRIC CONVERSION FACTORS

Following is an exhaustive list of conversion factors, courtesy of the
NASA web site listed above:

ATMOSPHERE (atm):
Def: The pressure exerted by 76 cm mercury with a density of 13.5951
gm/cm3 at 1g (the standard barometric pressure at sea level).
1 atm = 325 x 106 dynes/cm 2
1 atm = 1033.2 gm/cm 2
1 atm = 760 mm Hg
1 atm = 14.696 psi
1 atm = 101.329 kPa (kilo Pascals)

BRITISH THERMAL UNIT (Btu):
1 Btu = 1.0559 x 1010 ergs
1 Btu = 1055.9 joules
1 Btu = 251.995 gm-cal
1 Btu = 778.77 ft-lbs
1 Btu = 0.25199 kcal
1 Btu/hr = 0.1667 Btu/min
1 Btu/hr = 0.04199 kcal/min
1 Btu/hr = 0.2932 watt
1 Btu/min = 0.25199 kcal\min
1 Btu/min = 0.23599 hp
1 Btu/min = 17.595 watts
1 Btu/ft2, hr = 2.7125 kcal/m2 hr
Btu/hr to joules:
1 Btu/hr = 1.05435 x 103 joule/hr
800 Btu/hr x 1054.35 = 843480 joule/hr

CANDELA (cd):
1 cd = 1.018 candle

CANDLE (c):
The unit of luminous intensity.
1 c = 1 lumen/steradian

CELSIUS (°C):
(See Degrees Centigrade)

CELSIUS (°C):
(See Degrees Centigrade)

CENTIGRADE (°C):
(See Degrees Centigrade)

CENTIMETER (cm):
(See also Square Centimeter, Cubic Centimeter).
1 cm = 0.03280 ft
1 cm = 0.3937 in
1 cm = 0.01 m
1 cm = 10mm
1 cm = 1x104m (micron)

CENTIMETER-CANDLE (phot):
1 phot = 1 x 104 lux

CENTIMETERS PER SECOND PER SECOND:
1 cm/sec2 = 0.0328 ft/sec2

CLO (clo):
The unit of insulation resistance for clothing.
1 clo = 0.18°C m2hr/kcal
1 clo = 0.88°F ft2hr/Btu

CUBIC CENTIMETER (cc or cm3):
1 CC = 3.531 x 10-5 ft3
1 CC = 0.061023 in3
1 CC = 1 x 10-6 m3
1 CC = 1000 mm3
1 CC = 2.6417 x 10-4 gal (US fluid)
1 CC = 0.0338 oz (US fluid)
1 CC = 2.113 x 10-3 pint (US fluid)
1 cc/sec = 0.0021186 ft3/min

CUBIC FOOT
1 ft3 = 1728 in3
1 ft3 = 28.32 liters
1 ft3 = 0.02832 m3
1 ft3/min = 472.0 cc/sec
1 ft3/min = 0.4720 liter/sec
1 ft3/min = 62.43 lbs H2O/min
1 ft3/sec = 1699.3 liters/min

CUBIC INCH:
1 in3 = 5.787 x 10-4 ft3
1 in3 = 1.639 x 102 liter
1 in3 = 1.639 x 10-5 m3

CUBIC METER:
1 m3 = 35.3144 ft3
1 m3 = 6.1023 x 104 in3
1 m3 = 999.973 liters

DECIBEL (db):
Used for comparing power levels, acoustical or electrical. (See also Sound
Pressure Level).
1 db = 10 log10 P/PO
where P is the power to be compared to a reference power PO
1 db = 1 bel is equal to an increase in power (P) by a factor of 10

DEGREE (ANGULAR) (deg):
1 deg = 60 minutes
1 deg = 0.01745 radian
1 deg = 3600 seconds
1 deg = 1.7453 X 10-2 steradian --- note, this is changed from the original version that contains an error

DEGREES TO RADIANS:
1 deg = π/180 rad
60° x π/180 = 1.0472 = 1 rad

DEGREES CENTIGRADE (°C):
°C = 5/9 * (°F - 32)

DEGREES FAHRENHEIT (°F):
°F = (9/5 * °C) + 32

DEGREES PER SECOND:
1 deg/sec = 0.017453 radian/sec
1 deg/sec = 0.1667 rpm

DYNE (dyne):
1 dyne = 1.0197 x 10-6 kg
1 dyne = 2.2481 x 10-6 lb
1 dyne-cm = 1 erg

DYNE PER SQUARE CENTIMETER
1 dyne/cm2 = 9.8692 x 10-7 atm
1 dyne/cm2 = 0.0010197 gm/cm2
1 dyne/cm2 = 4.0148 x 10-4 in H2O
1 dyne/cm2 = 7.5006 x 10-4 mm Hg
1 dyne/cm2 = 1.4504 x 10-5 psi

ERG (erg):
1 erg = 9.4805 x 10-11 Btu
1 erg = 7.3756 x 10-8 ft-lb
1 erg = 2.3889 x 10-11 kcal
1 erg = 8.8510 x 10-7 lb-in
1 erg = 1 dyne-cm

FAHRENHEIT (°F):
(See Degrees Fahrenheit).

FOOT (ft):
(See also Square Foot, Cubic Foot).
1 ft = 30.48 cm
1 ft = 12 in
1 ft = 0.3048 m

FOOT-CANDLE (fc):
1 ft-c = 1 lumen/ft2
1 ft-c = 10.764 lumen/m2
1 ft-c = 10.75 lux

FOOT-LAMBERT (ft-L):
1 ft-L = 1.0764 millilamberts
1 ft-L = 0.32 decibels with respect to 1 mL

FOOT PER MINUTE
1 ft/min = 0.3048 m/min
1 ft/min = 0.005080 m/sec
1 ft/min = 0.011364 mph

FOOT PER SECOND:
1 ft/sec = 1.0973 km/hr
1 ft/sec = 0.5921 knot
1 ft/sec = 0.6818 mph

FOOT-POUND (ft-lb):
1 ft-lb = 0.001285 Btu
1 ft-lb = 1.3558 x 107 ergs
1 ft-lb = 3.2389 x 10-4 kcal
1 ft-lb/min = 3.0303 x 10-5 hp
1 ft-lb/min = 0.01667 ft-lb/sec
1 ft-lb/min = 0.022597 watt
1 ft-lb/sec = 0.001818 hp
1 ft-lb/sec = 0.01943 kcal/min
1 ft-lb/sec = 1.3558 watts

G (g):
The acceleration of gravity (also the acceleration of a vehicle).
1g = 9.81 m/s2
1 ft/sec = 1.0973 km/hr
1 ft/sec = 0.5921 knot
1 ft/sec = 0.6818 mph

GRAM (gm):
1 gm = 0.001 kg
1 gm = 1000 mg
1 gm = 0.03527 oz
1 gm = 0.0022046 lb
1 gm/cm3 = 62.428 lbs/ft3
1 gm/hr = 0.540 lb/day
1 gm/hr = 0.0003757 lb/min
1 gm/liter = 0.062427 lb/ft3
1 gm/cm2 = 9.6784 x 10-4 atm
1 gm/cm2 = 980.665 dynes/cm2
1 gm/cm2 = 0.9356 mm Hg
1 gm/cm2 = 0.014223 psi
1 gm/m2/hr = 2.78 x 10-5 gm/cm2/sec
1 gm/m2/hr = 0.7448 lb/ft2/hr

GRAM-CALORIE (gm-cal):
1 gm-cal = 30874 ft-lbs
1 gm-cal = 0.001 kcal

GRAY (Gy):
The International System of Units (SI) unit for the amount of ionizing
radiation energy absorbed by tissue.
1 Gy = 100 rads

HORSEPOWER (hp):
1 hp = 3.300 x 104 ft-lbs/min
1 hp = 550 ft-lbs/sec
1 hp = 10.688 kcal/min
1 hp = 745.7 watts

INCH (in):
(See also Cubic Inch, Square Inch)
1 in = 2.540 cm
1 in = 0.0833 ft
1 in = 25.40 mm

INCH OF WATER (in H2O):
1 in H2O (at 4°C) = 0.002458 atm
1 in H2O (at 4°C) = 2490.82 dynes/cm2
1 in H2O (at 4°C) = 0.0361 psi
1 in H2O (at 4°C) = 1.868 mm Hg

JOULE (joule):
1 joule = 1 watt-sec

KILOGRAM (kg):
1 kg = 1000 gm
1 kg = 2.205 lb
1 kg = 35.28 oz

KILOGRAM-CALORIE (kcal or large Calorie):
1 kcal = 3.9683 Btu
1 kcal = 4.186 x 1010 ergs
1 kcal = 1000 gm-cal
1 kcal = 3087 ft-lbs
1 kcal/hr = 0.0661 Btu/min
1 kcal/hr = 0.857 ft-lbs/sec
1 kcal/hr = 0.1667 kcal/min
1 kcal/hr = 1.161 watts
1 kcal/m2hr = 0.3687 Btu/ft2hr
1 kcal/min = 3.9685 Btu/min
1 kcal/min = 51.457 ft-lbs/sec
1 kcal/min = 0.093557 hp
1 kcal/min = 69.767 watts

KILOGRAM-CENTIMETER SQUARED:
1 kg-cm2 = 0.3417 lb-in2

KILOGRAM-METER PER SECOND:
1 kg-m/sec = 7.2330 ft-lb/sec
1 kg-m/sec = 9.80665 watts

KILOMETER (km):
1 km = 100,000 cm
1 km = 3281 ft
1 km = 103 meters, m
1 km = 0.6214 statute miles, mi
1 km = 0.54 nautical miles, nm

KILOPASCAL:
1kPa = 6.895 psi
1kPa = 4.754 x 105 dynes/cm2
1 psi = 0.145 kPa

KILOMETERS PER HOUR:
1 km/hr = 0.9113 ft/sec
1 km/hr = 0.5396 knot
1 km/hr = 0.6214 mph

KNOT (nautical mile per hour):
1 knot = 1.689 ft/sec
1 knot = 1.853 km/hr
1 knot = 1.1516 mph

LAMBERT (L): Unit of surface brightness.
1L = 0.3183 c/cm2
1L = 2.0536 c/in2
1L = 1 lumen/cm2

LITER (l):
1 liter = 0.03531 ft3
1 liter = 61.02 in3
1 liter = 1000 ml
1 liter/min = 5.886 x 10-4 ft3/sec
1 liter/sec = 2.12 ft3/min

LUMEN (lumen):
1 lumen = 0.001496 watt
1 lumen = 0.07958 spherical candle power
1 lumen/ft2 = 1 ft-c
1 lumen/ft2 = 10.764 lumen/m2

LUMENS PER SQ. METER TO FT CANDLES:
1 lumen/m2 = 0.0929 ft. candle

LUX:
1 lux = 0.093 ft-c (see meter-candle)

METER (m):
(See also Cubic Meter).
1m = 100 cm
1m = 3.281 ft
1m = 39.37 in

METER-CANDLE (lux):
1 lux = 1 lumen/m2
1 lux = 0.092903 ft-c

METER PER SECOND (m/sec):
1 m/sec = 3.281 ft/sec
1 m/sec = 3.600 km/hr
1 m/sec = 2.2369 mph

MICRON (μ or mu):
A unit of length equal to one-millionth of a meter or one-thousandth of a
millimeter, usually called micrometer.
1 μ = 10-6 meter
1 μ = 3.937 x 10-5 in
1 μ = 0.001 mm

MIL (mil):
1 mil = 0.001 in
1 mil = 0.0254 mm
1 mil = 25.40μ (microns)

MILES (statute) (mi):
1 mi = 1,609 x 105 cm
1 mi = 5,280 ft
1 mi = 1.609 km

MILES PER HOUR (mph)
1 mph = 88 ft/min
1 mph = 1.4667 ft/sec
1 mph = 1.6093 km/hr
1 mph = 0.8684 knot

MILLIGRAM (mg):
1 mg = 0.001 gm
1 mg = 3.5274 x 10-5 oz
1 mg = 2.2046 x 10-6 lb
1 mg/m3 = 6.243 x 10-4 lb/ft3

MILLILAMBERT (ml):
(perfectly diffused light)
1 mL = 0.929 lumen/ft2

MILLILITER (ml):
1 ml = 1.000028 cc
1 ml = 0.061025 in3
1 ml = 0.001 liter
1 ml = 0.0338 oz (US fluid)

MILLILITERS PER HOUR:
1 ml/hr = 0.06102 in3/hr

MILLIMETER (mm):
(See also Square Millimeter)
1mm = 0.10 cm
1mm = 0.03937 in
1mm = 1000 μ

MILLIMETER OF MERCURY (mm Hg):
1mm Hg (at 0°C) = 0.0013158 atm
1mm Hg (at 0°C) = 1333.22 dyne/cm2
1mm Hg (at 0°C) = 1.3595 gm/cm2
1mm Hg (at 0°C) = 0.019337 psi
1mm Hg (at 0°C) = 0.535 in H2O
1mm Hg (at 0°C) = 0.1333 kPa

MILLISECONDS (msec):
1 msec = 0.001 sec

NAUTICAL MILES (nm):
1 nm = 0.87 statute miles
1 nm = 1.85 kilometers

NEWTONS TO POUNDS:
1 N = 0.22507 lbf

NEWTON CENTIMETERS TO INCH OUNCES:
1 N-cm = 1/.706 in oz
70N-cm x 1/.706 = 99.15 = 100 in oz

NEWTON METERS TO FOOT POUNDS:
1Nm = 1/1.356 ft lb
15Nm x 1/1.356 = 11.06 = 11 ft lb

NEWTON METERS TO INCH POUNDS:
1 Nm = 1/.11298 in lb
4 Nm x 1/.11298 = 35.4 = 3 5 in lb

NIT:
Unit of luminance equal to the luminance provided by one candle of radiant
flux emitted per square meter of surface - candela per square meter (Cd m2).

OUNCE (oz):
1 oz = 28.3495 gm
1 oz = 0.0625 lb

PASCALS (Pa)
Pa = 4.75389 dynes/cm2
Pa = 6.895 x 10-3 psi

PARTS PER MILLION (ppm).
1 ppm = 1.0 mg/liter of H2O
1 ppm = 8.345 lbs/million gallons

PHON (phon):
1 phon unit = SPL of a 1000 cycle/sec tone

PHOT:
(See Centimeter Candle)

PHYSICAL CONSTANTS:
Acceleration of gravity (g) = 32.17 ft/sec²= 980.6 cm/sec²
Avogadro's number (N) = 6.0221367 x 10²³ molecules/gram-mole
Density of air at 0°C and 760 mm Hg = 0.0012929 grams/cm³(0.0807
lb/ft³)
Density of water at 0°C = .099984 grams/cm³
Heat of fusion of water at 1.0 atm = 79.7 calories/gram = 144 Btu/pound
Heat of vaporization of water at 1.0 atm = 540 calories/gram = 970 Btu/
pound
Naperian-logarithm base = 2.71828183
Pi (π) = 3.14159265
Specific heat of air = Cp = 0.238 cal/gram (°C)
Velocity of light (c) = 2.99792458 x 1010 cm/sec
Velocity of sound in dry air at 0°C, 1 atm = 33,136 cm/sec = 1,089 feet/sec

POISE: Unit of viscosity.
1 poise = 1 dyne/sec, cm2
1 poise = 1 gm/cm, sec
1 poise = 0.067196 lb/ft, sec

POUND (lb):
1 lb = 453.5924 gm
1 lb = 0.45359 kg
1 lb = 16 oz
1 lb = 4.448 N
1 lb/day = 18.89 gm/hr
1 lb/hr = 0.7559 gm/min
1 lb/hr = 10.886 kg/day

POUND-INCH (lb-in):
1 lb-in = 1.1298 x 106 dyne/cm

POUND-INCH SQUARED:
Unit of moment of inertia
1 lb-in2 = 2.9264 kg-cm2

POUND OF WATER PER MINUTE (lb H2O/min):
1 lb H2O/min = 0.01603 ft3/min
1 lb H2O/min = 2.670 x 10-4 ft3/sec

POUND PER CUBIC FOOT (lb/ft3):
1 lb/ ft3 = 0.01602 gm/ cm3

POUNDS PER SQUARE INCH (psi):
1 psi = 0.06805 atm
1 psi = 6.8947 x 104 dyne/cm2
1 psi = 70.307 gm/cm2
1 psi = 51.715 mmHg
1 psi = 27.7 in H2O
1 psi = 145.03 Pa

POUNDS PER SQUARE INCH ABSOLUTE (psia):
Absolute pressure, where 0 psia = vacuum
1 psia = 0.1449 kpascals

POUND WEIGHT (1 wt):
1 lb wt = 4.4482 x 105 dynes
1 lb wt = 453.59 gm wt
1 lb wt = 16 oz

RAD (rad):
Radiation absorbed dose.
1 rad = 100 ergs/gm of irradiated material

RADIAN (rad):
1 radian = ½π circumference revolution (0.15915)
1 radian = 57.296 deg
1 radian/sec = 57.296 deg/sec
1 radian/sec = 9.549 rpm
1 radian/sec2 = 572.96 rpm2

REVOLUTIONS PER MINUTE (rpm):
1 rpm = 6 deg/sec
1 rpm = 0.10472 radian/sec
1 rpm2 = 0.001745 radian/sec2

ROENTGEN (r):
1 r = ionization by x-rays or gamma-rays producing 1 electrostatic unit
of charge in 1 cm3 of air (STP)
1 r = 83.0 ergs/gm

SIEVERT (Sv):
Sv is the International System of Units (SI) unit for ionizing radiation dose
equivalent. (Refer to Figure 5.7.2.1.3.1-1 for definition of Q values)
1 Sv = 100 rem = (Gy) (Q)

SOUND PRESSURE LEVEL (SPL):
SPL is sound pressure related logarithmically to a reference level of pressure
(Po), which by convention is 0.0002 dynes/cm2. The defining equation is:
SPL = 20 log10 P/PO in decibels

SQUARE CENTIMETER (cm2):
1 cm2 = 1.076 x 10-3 ft2
1 cm2 = 0.1550 in2
1 cm2 = 100 mm2

SQUARE FOOT (ft2):
1 ft2 = 929.0304 cm2
1 ft2 = 144 in2

SQUARE INCH (in2):
1 in2 = 6.4516 cm2
1 in2 = 0.006944 ft2
1 in2 = 645.1626 mm2

SQUARE MILLIMETER (mm2):
1 mm2 = 0.01 cm2
1 mm2 = 0.001550 in2