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Conversion Tables for Vacuum Products

PRESSURE UNITS

  mbar bar torr Pa(Nm-2) atm lbf in-2 kgf cm-2 in Hg mmHg in H20 mm H2O
1 mbar = 1 1x10-3 0.75 102 9.869 x 10-4 1.45 x 10-2 1.02 x 10-3 2.953 x 10-2 0.75 0.402 10.197
1 bar = 103 1 7.5 x 102 1 x 105 0.987 14.5 1.02 29.53 7.5 x 102 4.015 x 102 1.02 x 104
1 torr = 1.333 1.333 x 10-3 1 1.333 x 102 1.316 x 10-1 1.934 x 10-2 1.36 x -3 3.937 x -2 1 0.535 13.59
1 Pa (Nm-2)= 0.01 1 x 10-5 7.5 x 10-3 1 9.87 x 10-6 1.45 x 10-4 1.02 x 10-5 2.953 x 10-4 7.5 x 10-3 4.015 x 10-3 0.102
1 atm = 1.013 x 103 1.013 7.6 x 102 1.013 x 105 1 14.7 1.033 29.92 7.6 x 102 4.068 x 102 1.033x104
1 lbin-2= 68.95 6.895 x 10-2 51.71 6.895 x 103 6.805 x 10-2 1 7.03 x 10-2 2.036 51.71 27.68 7.03 x 102
1 kgf cm-2= 9.807 x 102 0.981 7.356 x 102 9.807 x 104 0.968 14.22 1 28.96 7.356 x 102 3.937 x 102 104
1 in Hg = 33.86 3.386 x 10-2 25.4 3.386 x 103 3.342 x 10-2 0.491 3.453 x 10-2 1 25.4 13.6 3.45 x 102
1 mm Hg = 1.333 1.333 x 10-3 1 1.333 x 102 1.316 x 10-3 1.934 x 10-2 1.36 x 10-3 3.937 x 10-2 1 0.535 13.59
1 in H2O = 2.491 2.491 x 10-3 1.868 2.491 x 102 2.458 x 10-3 3.613 x 10-2 2.54 x 10-3 7.356 x 10-2 1.868 1 25.4
1 mm H2O= 9.807 x 10-2 9.807 x 10-5 7.354 x 10-2 9.807 9.677 x 10-5 1.42 x 10-3 10-4 2.896 x 10-3 7.354 x 10-2 3.394 x 10-2 1

Note also: 1 dyn cm-2 (barye) = 0.1 Pa (Nm-2) = 10-3 mbar.

LEAK RATE UNITS

  mbar l s-1 torr l s-1 atm cm3s-1 lusec atm ft3 min-1 grams per year
(Freon 12)
1 mbar l s-1 = 1 0.75 0.987 7.5 x 102 2.097 x 10-3 1.58 x 105
1 torr l s-1 = 1.333 1 1.316 103 2.795 x 10-3 2.083 x 105
1 atm cm3s-1 = 1.013 0.76 1 7.6 x 102 2.12 x 10-3 1.582 x 105
1 lusec = 1.333 x 10-3 0.001 1.32 x 10-3 1 2.79 x 10-6 2.083 x 102
1 atm ft3min-1 = 4.78 x 102 3.58 x 102 4.72 x 102 3.58 x 105 1 7.45 x 107
1 gram per year
(Freon 12)		 6.4 x 10-6 4.8 x 10-6 6.32 x 10-6 4.8 x 10-3 1.34 x 10-8 1

PUMPING SPEED UNITS

  l s-1 = l min-1 ft3min-1 m3h-1
1 l s-1 = 1 60 2.12 3.60
1 l min-1 = 0.0167 1 0.0353 0.06
1 ft3min-1= 0.472 28.32 1 1.70
1 m3h-1 = 0.278 16.67 0.589 1


Conversion Factors

Converting Pressures Units

PRESSURE
To ConvertIntoMultiply
atmospherebar1.01295
atmospheredynes/cm21.01295 x 106
atmospherein. Hg29.9213
atmospherein. water406.86
atmospherekg/cm21.03325
atmospherembar1012.95
atmospheremtorr or micron Hg7.6 x 105
atmospherePa or N/m21.01295 x 105
atmospherepsi or lb/in214.696
atmospheretorr or mm Hg760.00
baratmosphere0.9872
bardynes/cm21 x 106
barin. Hg29.54
barin. water401.65
barkg/cm21.0200
barmbar1000
barmtorr or micron Hg7.5028 x 105
barPa or N/m21 x 105
barpsi or lb/in214.508
bartorr or mm Hg750.2838
PRESSURE
To ConvertIntoMultiply
dynes/cm2atmosphere9.872 x 10-7
dynes/cm2bar1 x 10-6
dynes/cm2in. Hg2.954 x 10-5
dynes/cm2in. water4.0165 x 10-4
dynes/cm2kg/cm21.0200 x 10-6
dynes/cm2mbar1 x 10-3
dynes/cm2mtorr or micron Hg0.75028
dynes/cm2Pa or N/m20.1
dynes/cm2psi or lb/in21.4508 x 10-5
dynes/cm2torr or mm Hg7.5028 x 10-4
in. Hgatmosphere3.342 x 10-2
in. Hgbar3.385 x 10-2
in. Hgdynes/cm23.385 x 104
in. Hgin. water13.598
in. Hgkg/cm23.4532 x 10-2
in. Hgmbar33.85
in. Hgmtorr or micron Hg2.54 x 104
in. HgPa or N/m23385
in. Hgpsi or lb/in20.4912
in. Hgtorr or mm Hg25.4
PRESSURE
To ConvertIntoMultiply
in. wateratmosphere2.458 x 10-3
in. waterbar2.489 x 10-3
in. waterdynes/cm22.489 x 103
in. waterkg/cm22.5396 x 10-3
in. waterin. Hg7.354 x 10-2
in. watermbar2.489
in. watermtorr or micron Hg1.868 x 103
in. waterPa or N/m2248.9
in. waterpsi or lb/in23.612 x 10-2
in. watertorr or mm Hg1.868
kg/cm2atmosphere0.9678
kg/cm2bar0.9804
kg/cm2dynes/cm29.804 x 105
kg/cm2in. Hg28.958
kg/cm2in. water393.76
kg/cm2mbar9.804 x 102
kg/cm2mtorr or micron Hg7.3554 x 105
kg/cm2Pa or N/m29.804 x 104
kg/cm2psi or lb/in214.223
PRESSURE
To ConvertIntoMultiply
kg/cm2torr or mm Hg7.3554 x 102
mbaratmosphere9.872 x 10-4
mbarbar0.001
mbardynes/cm21000
mbarkg/cm21.0200 x 10-3
mbarin. Hg2.954 x 10-2
mbarin. water0.4018
mbarmtorr or micron Hg7.5028 x 102
mbarPa or N/m2100
mbarpsi or lb/in21.450 x 10-2
mbartorr or mm Hg0.75028
mtorr or micron Hgatmosphere1.316 x 10-6
mtorr or micron Hgbar1.3328 x 10-6
mtorr or micron Hgdynes/cm21.3328
mtorr or micron Hgkg/cm21.3595 x 10-6
mtorr or micron Hgin. Hg3.937 x 10-5
mtorr or micron Hgin. water5.353 x 10-4
mtorr or micron Hgmbar1.3328 x 10-3
mtorr or micron HgPa or N/m20.13328
mtorr or micron Hgpsi or lb/in21.934 x 10-5
PRESSURE
To ConvertIntoMultiply
mtorr or micron Hgtorr1 x 10-3
Pa or N/m2atmosphere9.869 x 10-6
Pa or N/m2bar1 x 10-5
Pa or N/m2dynes/cm210
Pa or N/m2kg/cm21.020 x 10-5
Pa or N/m2in. Hg2.954 x 10-4
Pa or N/m2in. water4.018 x 10-3
Pa or N/m2mbar0.01
Pa or N/m2mtorr or micron Hg7.5028
Pa or N/m2psi or lb/in21.4508 x 10-4
Pa or N/m2torr or mm Hg7.5028 x 10-3
psi or lb/in2atmosphere0.06805
psi or lb/in2bar0.06893
psi or lb/in2dynes/cm26.8927 x 104
psi or lb/in2kg/cm27.0309 x 10-2
psi or lb/in2in. Hg2.036
psi or lb/in2in. water27.68
psi or lb/in2mbar68.97
psi or lb/in2mtorr or micron Hg5.171 x 104
psi or lb/in2Pa or N/m26.8927 x 103
PRESSURE
To ConvertIntoMultiply
psi or lb/in2torr or mm Hg51.71
torr or mm Hgatmosphere1.3158 x 10-3
torr or mm Hgbar1.3328 x 10-3
torr or mm Hgdynes/cm21.3328 x 103
torr or mm Hgkg/cm21.3595 x 10-3
torr or mm Hgin. Hg3.937 x 10-2
torr or mm Hgin. water0.5353
torr or mm Hgmbar1.3328
torr or mm Hgmtorr or micron Hg1000
torr or mm HgPa or N/m2133.28
torr or mm Hgpsi or lb/in21.934 x 10-2

Converting Pumping Speed Units

PUMPING SPEED
To ConvertIntoMultiply
ft3/minL/sec0.47195
ft3/minm3/hr1.69901
L/hrL/sec2.77778 x 10-4
L/minL/sec1.66667 x 10-2
L/secft3/min2.11887
L/secm3/sec0.001
L/secm3/hr3.6
m3/hrft3/min0.58858
m3/hrL/sec0.27778

Converting Throughput Units

THROUGHPUT
To ConvertIntoMultiply
atm.cc/secPa.L/sec101.295
atm.cc/secmolecules/sec2.6868 x 1019
atm.cc/sectorr.L/sec0.7600
atm.cc/secwatt0.10143
micron.L/secPa.L/sec0.13328
molecules/secatm.cc/sec3.7219 x 10-20
molecules/secPa.L/sec3.7701 x 10-18
molecules/sectorr.L/sec2.8287 x 10-20
molecules/secwatt3.7701 x 10-21
Pa.L/secatm.cc/sec9.872 x 10-3
Pa.L/secmolecules/sec2.652 x 1017
Pa.L/secPa.m3/hr3.6
Pa.L/sectorr.L/sec7.5028 x 10-3
Pa.L/secwatt10-3
torr.L/secatm.cc/sec1.31579
torr.L/secwatt0.13328
torr.L/secmolecules/sec3.5352 x 1019
torr.L/secPa.L/sec133.28
wattatm.cc/sec9.859
wattmolecules/sec2.5 x 1020
wattPa.L/sec1000
watttorr.L/sec7.503

Converting Outgassing Units

OUTGASSING
To ConvertIntoMultiply
micron.L/(cm2.sec)Pa.L/(m2.sec)1332.8
micron.L/(cm2.sec)Pa.m3/(m2.sec)1.3328
micron.L/(cm2.sec)torr.L/(cm2.sec)1 x 10-3
micron.L/(cm2.sec)W/m21.3328
Pa.L/(m2.sec)Pa.m3/(m2.sec)1 x 10-3
Pa.L/(m2.sec)micron.L/(cm2.sec)7.5 x 10-4
Pa.L/(m2.sec)torr.L/(cm2.sec)7.5 x 10-7
Pa.L/(m2.sec)W/m21 x 10-3
Pa.m3/(m2.sec)micron.L/(cm2.sec)0.75
Pa.m3/(m2.sec)Pa.L/(m2.sec)1000
Pa.m3/(m2.sec)torr.L/(cm2.sec)7.5 x 10-4
Pa.m3/(m2.sec)W/m21
torr.L/(cm2.sec)micron.L/(cm2.sec)1000
torr.L/(cm2.sec)Pa.L/(m2.sec)1.3332 x 106
torr.L/(cm2.sec)Pa.m3/(m2.sec)1333.2
torr.L/(cm2.sec)W/m21333.2
W/m2micron.L/(cm2.sec)0.75
W/m2Pa.L/(m2.sec)1000
W/m2Pa.m3/(m2.sec)1
W/m2torr.L/(cm2.sec)7.50 x 10-4

Converting Weights and Measure Units

WEIGHTS & MEASURES
To ConvertIntoMultiply
ampere-turngilbert1.257
ampere-turn/cmampere-turn/in2.54
ampere-turn/ingilbert/cm0.495
ampere-turn/inampere-turn/cm0.3937
ampere/cm2ampere/in26.452
angstrommicroinch0.00393
angstrommillimicron0.1
angstromcm10-8
angstromnanometer0.1
angstrommicron10-4
b/mil ftgrams/cm32.306 x 106
Btujoule1054
Btukilowatt-hour2.929 x 10-4
Btuft-lb777.6
Btu/minutewatt17.57
calorie (kg)joule4184
calorie (kg)Btu3.968
calorie (kg)horsepower hr.1.558 x 10-3
calorie (kg)ft-lb3086
calories (kg)kilowatt-hour1.162 x 10-3
WEIGHTS & MEASURES
To ConvertIntoMultiply
circular milcm25.067 x 10-6
circular milin27.854 x 10-7
circular milsq mil0.7854
cmmil393.7
cminch0.3937
cmangstrom108
cm2ft21.076 x 10-3
cm2circular mil1.974 x 105
cm2in20.155
cm3gallon2.642 x 10-4
cm3in36.102 x 10-2
cm3quarts (liquid)1.057 x 10-3
cm3liter10-3
cm3ft33.531 x 10-5
cm3pints (liquid)2.113 x 10-3
coulombs/in2coulombs/cm20.155
degree (angle)minute60
degree (angle)second3600
degree (angle)radian0.01745
degree/secradian/sec0.01745
WEIGHTS & MEASURES
To ConvertIntoMultiply
degree/secrevolution/sec0.002778
degree/secrpm0.1667
dynepound2.248 x 10-6
dynegram1.020 x 10-3
dynes/cm2bar1 x 10-6
ergdyne-cm1
ergkg-meter1.020 x 10-8
erggram-cm1.020 x 10-3
ergft-lb7.376 x 10-8
ergkg-calorie2.390 x 10-11
ergjoule10-7
ergBtu9.486 x 10-11
ergs/secBtu/min5.691 x 10-9
ergs/seckilowatt10-10
ergs/secft-lb/min4.42 x 10-6
feetcm30.48
feetmeter0.3048
ft-lbmeter-kilogram0.1383
ft-lbcm-gram13.826
ft-lbcm-dyne1.356 x 107
WEIGHTS & MEASURES
To ConvertIntoMultiply
ft2in2144
ft2m20.0929
ft2cm2929.0
ft3lb. water62.4
ft3liter28.32
ft3pint (liquid)59.84
ft3cm32.832 x 104
ft3in31728
ft3m30.02832
ft3quart (liquid)29.92
ft3gallon7.481
ft3yd30.03704
ft3/mingallon/sec0.1247
ft3/mincm3/sec471.9
ft3/minliter/sec0.4719
gallonquart (liquid)4
gallonliter3.785
galloncm33785
gallonpint (liquid)8
gallonft30.1337
WEIGHTS & MEASURES
To ConvertIntoMultiply
gallonlb. water8.34
gallonin3231
gallonm33.785 x 10-3
gallon/minliter/sec0.064
gallon/minft3/sec2.228 x 10-3
gausslines/in26.452
gilbertampere-turn0.7958
gramoz0.03527
gramdyne980.7
gramlb2.205 x 10-3
gram-calorieBtu3.968 x 10-3
gram-cmkg-meter10-5
gram-cmjoule9.807 x 10-5
gram-cmft-lb7.233 x 10-5
gram-cmerg980.7
gram-cmBtu9.302 x 10-8
gram-cmkg-calorie2.344 x 10-8
gram/cmlb/in5.6 x 10-3
gram/cm3lb/circular mil ft3.405 x 10-7
gram/cm3lb/in30.03613
WEIGHTS & MEASURES
To ConvertIntoMultiply
gram/cm3lb/ft362.43
horsepowerhorsepower
(metric)		1.014
horsepowerwatt745.7
in2ft26.944 x 10-3
in2cm26.452
in2sq mil106
in2mm2645.2
in2circular mil1.273 x 106
in3pint (liquid)0.0346322
in3quart (liquid)0.01732
in3liter1.639 x 10-2
in3gallon4.329 x 10-3
in3m31.639 x 10-5
in3ft35.787 x 10-4
in3cm316.39
inchangstrom2.54 x 108
inchcm2.54
joulewatt-hour2.778 x 10-4
joulekg-meter0.1020
joulekg-calorie2.390 x 10-4
WEIGHTS & MEASURES
To ConvertIntoMultiply
jouleft-lb0.7377
jouleerg107
jouleBtu9.486 x 10-4
kilogramtons (short)1.102 x 10-3
kilogramlb2.2046
kilogram (force)dyne980,665
kilogram-meterkilowatt-hour2.724 x 10-6
kilolinemaxwell103
kilometermile0.6214
kilometerfeet3281
kilowattft-lb/sec737.6
kilowattft-lb/min4.425 x 104
kilowattBtu/minute56.92
kilowatt-hourkilogram-meter3.671 x 105
kilowatt-hourjoule3.6 x 106
kilowatt-hourft-lb2.655 x 106
kilowatt-hourBtu3415
km/hourm/min16.67
km/hourmile/hour0.6214
km/hourft/sec0.9113
WEIGHTS & MEASURES
To ConvertIntoMultiply
km/hourft/min54.68
km/hourcm/sec27.78
km2ft21.076 x 107
lb watergallon0.1198
lb waterin327.68
lb waterft30.01602
lb water/minft3/sec2.669 x 10-4
lb/ftkg/meter1.488
lb/ft2kg/m24.882
lb/ft2ft. water0.01602
lb/ft2lb/in26.944 x 10-3
lb/ingrams/cm178.6
lb/in.2lb/ft2144
lb/in.2kg/m2703.1
lb/in.2in. Hg2.036
lb/in.2ft. water2.307
lb/in.2atmosphere0.06804
lines/cm2gauss1
lines/in2gauss0.155
literquart (liquid)1.057
WEIGHTS & MEASURES
To ConvertIntoMultiply
literpint (liquid)2.113
litergallon0.2642
literin361.02
literft30.03531
liter/mingallon/sec4.403 x 10-3
liter/minft3/sec5.885 x 10-4
lumen/ft2foot-candle1
m/minmiles/hour0.03728
m/minkm/hour0.06
m/minft/sec0.05468
m/secmiles/min0.03728
m/seckm/min0.06
m/seckm/hr3.6
m/secft/sec3.281
m/secft/min196.8
m/secmiles/hour2.237
m2sq mile3.861 x 10-7
m2ft210.764
m3quarts (liquid)1057
m3pints (liquid)2113
WEIGHTS & MEASURES
To ConvertIntoMultiply
m3gallon264.2
m3in361,024
m3ft335.31
m3cm3106
maxwellkiloline10-3
megalinemaxwell106
meterinch39.37
meterfeet3.2808
meterangstrom1010
mhos/mil ftmegmhos/in315.28
mhos/mil ftmegmhos/cm36.015
microhm/cm3ohms/mil ft6.015
microhm/cm3microhms/in30.3937
microhm/in3microhm/cm32.54
microinchangstrom254
micromicronangstrom0.01
micronangstrom10,000
milinch10-3
milcm0.0025
millilitercm31.0
WEIGHTS & MEASURES
To ConvertIntoMultiply
millimetermil39.37
millimetermicron1000
millimeterinch0.03937
millimeterangstrom107
millimicronangstrom10
minuteseconds (angle)60
minutes (angle)radian2.909 x 10-4
mm2in21.55 x 10-3
mm2cm20.01
mm2circular mil1.974 x 103
nanometermicron10-3
ohms/mil ftmicrohm/in30.06524
ohms/mil ftmicrohm/cm30.1662
ounces (fluid)liter0.02957
ounces (fluid)in31.805
oz/in2psi0.0625
pints (liquid)in328.88
pints (dry)in333.6
poundoz16
poundgram453.6
WEIGHTS & MEASURES
To ConvertIntoMultiply
pound (force)dyne444,823
quadrants (angle)radian1.571
quadrants (angle)minute5400
quadrants (angle)degree90
quartfluid ounce32
quarts (liquid)in357.75
quarts (dry)in367.2
radiandegrees/sec57.3
radianquandrant0.637
radianminute3438
radiandegree57.3
radians/secrevolutions/sec0.1592
radians/secrpm9.549
revolutionradian6.283
revolutionquadrant4
revolutiondegree360
revolutions/secrpm60
revolutions/secradians/sec6.283
revolutions/secdegrees/sec360
rpmrevolutions/sec0.01667
WEIGHTS & MEASURES
To ConvertIntoMultiply
rpmradians/sec0.1047
rpmdegrees/sec6
seconds (angle)radian4.848 x 10-6
spheres (solid angle)steradian12.57
spherical rt. anglesteradian1.571
spherical rt. anglesphere0.125
spherical rt. anglehemisphere0.25
steradiansphere0.07958
steradianhemisphere0.1592
stereliter103
tons (short)lb2000
tons (short)kg907.2
tons (metric)lb2205
tons (metric)kg103
tons (long)lb2240
tons (long)kg1016
wattkilowatt10-3
wattft-lb/sec0.7376
wattft-lb/min44.25
wattergs/sec107
wattBtu/min0.05692
watt-hourkilogram-meter367.1
watt-hourft-lb2655
watt-hourBtu3.414
webermaxwell108

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