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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 H}2^{O =}}	^{^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 H}2^O=}	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 ft^{3 min^-1}	grams per year (Freon 12)
1 mbar l s^{^-1} =	1	0.75	0.987	7.5 x 10^²	2.097 x 10^{^-3}	1.58 x 10^⁵
1 torr l s^{^-1} =	^1.333	1	1.316	10^³	2.795 x 10^{^-3}	2.083 x 10^⁵
1 atm cm^³s^{^-1}=	1.013	0.76	1	7.6 x 10^²	2.12 x 10^{^-3}	1.582 x 10^⁵
1 lusec =	1.333 x 10^{^-3}	0.001	1.32 x 10^{^-3}	1	2.79 x 10^{^-6}	2.083 x 10^²
1 atm ft^³min^{^-1} =	4.78 x 10^²	3.58 x 10^²	4.72 x 10^²	3.58 x 10^⁵	1	7.45 x 10^⁷
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}	ft^³min-1	m^³h^{^-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 Convert	Into	Multiply
atmosphere	bar	1.01295
atmosphere	dynes/cm²	1.01295 x 10⁶
atmosphere	in. Hg	29.9213
atmosphere	in. water	406.86
atmosphere	kg/cm²	1.03325
atmosphere	mbar	1012.95
atmosphere	mtorr or micron Hg	7.6 x 10⁵
atmosphere	Pa or N/m²	1.01295 x 10⁵
atmosphere	psi or lb/in²	14.696
atmosphere	torr or mm Hg	760.00
bar	atmosphere	0.9872
bar	dynes/cm²	1 x 10⁶
bar	in. Hg	29.54
bar	in. water	401.65
bar	kg/cm²	1.0200
bar	mbar	1000
bar	mtorr or micron Hg	7.5028 x 10⁵
bar	Pa or N/m²	1 x 10⁵
bar	psi or lb/in²	14.508
bar	torr or mm Hg	750.2838
PRESSURE
To Convert	Into	Multiply
dynes/cm²	atmosphere	9.872 x 10^-7
dynes/cm²	bar	1 x 10^-6
dynes/cm²	in. Hg	2.954 x 10^-5
dynes/cm²	in. water	4.0165 x 10^-4
dynes/cm²	kg/cm²	1.0200 x 10^-6
dynes/cm²	mbar	1 x 10^-3
dynes/cm²	mtorr or micron Hg	0.75028
dynes/cm²	Pa or N/m²	0.1
dynes/cm²	psi or lb/in²	1.4508 x 10^-5
dynes/cm²	torr or mm Hg	7.5028 x 10^-4
in. Hg	atmosphere	3.342 x 10^-2
in. Hg	bar	3.385 x 10^-2
in. Hg	dynes/cm²	3.385 x 10⁴
in. Hg	in. water	13.598
in. Hg	kg/cm²	3.4532 x 10^-2
in. Hg	mbar	33.85
in. Hg	mtorr or micron Hg	2.54 x 10⁴
in. Hg	Pa or N/m²	3385
in. Hg	psi or lb/in²	0.4912
in. Hg	torr or mm Hg	25.4
PRESSURE
To Convert	Into	Multiply
in. water	atmosphere	2.458 x 10^-3
in. water	bar	2.489 x 10^-3
in. water	dynes/cm²	2.489 x 10³
in. water	kg/cm²	2.5396 x 10^-3
in. water	in. Hg	7.354 x 10^-2
in. water	mbar	2.489
in. water	mtorr or micron Hg	1.868 x 10³
in. water	Pa or N/m²	248.9
in. water	psi or lb/in²	3.612 x 10^-2
in. water	torr or mm Hg	1.868
kg/cm²	atmosphere	0.9678
kg/cm²	bar	0.9804
kg/cm²	dynes/cm²	9.804 x 10⁵
kg/cm²	in. Hg	28.958
kg/cm²	in. water	393.76
kg/cm²	mbar	9.804 x 10²
kg/cm²	mtorr or micron Hg	7.3554 x 10⁵
kg/cm²	Pa or N/m²	9.804 x 10⁴
kg/cm²	psi or lb/in²	14.223
PRESSURE
To Convert	Into	Multiply
kg/cm²	torr or mm Hg	7.3554 x 10²
mbar	atmosphere	9.872 x 10^-4
mbar	bar	0.001
mbar	dynes/cm²	1000
mbar	kg/cm²	1.0200 x 10^-3
mbar	in. Hg	2.954 x 10^-2
mbar	in. water	0.4018
mbar	mtorr or micron Hg	7.5028 x 10²
mbar	Pa or N/m²	100
mbar	psi or lb/in²	1.450 x 10^-2
mbar	torr or mm Hg	0.75028
mtorr or micron Hg	atmosphere	1.316 x 10^-6
mtorr or micron Hg	bar	1.3328 x 10^-6
mtorr or micron Hg	dynes/cm²	1.3328
mtorr or micron Hg	kg/cm²	1.3595 x 10^-6
mtorr or micron Hg	in. Hg	3.937 x 10^-5
mtorr or micron Hg	in. water	5.353 x 10^-4
mtorr or micron Hg	mbar	1.3328 x 10^-3
mtorr or micron Hg	Pa or N/m²	0.13328
mtorr or micron Hg	psi or lb/in²	1.934 x 10^-5
PRESSURE
To Convert	Into	Multiply
mtorr or micron Hg	torr	1 x 10^-3
Pa or N/m²	atmosphere	9.869 x 10^-6
Pa or N/m²	bar	1 x 10^-5
Pa or N/m²	dynes/cm²	10
Pa or N/m²	kg/cm²	1.020 x 10^-5
Pa or N/m²	in. Hg	2.954 x 10^-4
Pa or N/m²	in. water	4.018 x 10^-3
Pa or N/m²	mbar	0.01
Pa or N/m²	mtorr or micron Hg	7.5028
Pa or N/m²	psi or lb/in²	1.4508 x 10^-4
Pa or N/m²	torr or mm Hg	7.5028 x 10^-3
psi or lb/in²	atmosphere	0.06805
psi or lb/in²	bar	0.06893
psi or lb/in²	dynes/cm²	6.8927 x 10⁴
psi or lb/in²	kg/cm²	7.0309 x 10^-2
psi or lb/in²	in. Hg	2.036
psi or lb/in²	in. water	27.68
psi or lb/in²	mbar	68.97
psi or lb/in²	mtorr or micron Hg	5.171 x 10⁴
psi or lb/in²	Pa or N/m²	6.8927 x 10³
PRESSURE
To Convert	Into	Multiply
psi or lb/in²	torr or mm Hg	51.71
torr or mm Hg	atmosphere	1.3158 x 10^-3
torr or mm Hg	bar	1.3328 x 10^-3
torr or mm Hg	dynes/cm²	1.3328 x 10³
torr or mm Hg	kg/cm²	1.3595 x 10^-3
torr or mm Hg	in. Hg	3.937 x 10^-2
torr or mm Hg	in. water	0.5353
torr or mm Hg	mbar	1.3328
torr or mm Hg	mtorr or micron Hg	1000
torr or mm Hg	Pa or N/m²	133.28
torr or mm Hg	psi or lb/in²	1.934 x 10^-2

Converting Pumping Speed Units

PUMPING SPEED
To Convert	Into	Multiply
ft³/min	L/sec	0.47195
ft³/min	m³/hr	1.69901
L/hr	L/sec	2.77778 x 10^-4
L/min	L/sec	1.66667 x 10^-2
L/sec	ft³/min	2.11887
L/sec	m³/sec	0.001
L/sec	m³/hr	3.6
m³/hr	ft³/min	0.58858
m³/hr	L/sec	0.27778

Converting Throughput Units

THROUGHPUT
To Convert	Into	Multiply
atm.cc/sec	Pa.L/sec	101.295
atm.cc/sec	molecules/sec	2.6868 x 10¹⁹
atm.cc/sec	torr.L/sec	0.7600
atm.cc/sec	watt	0.10143
micron.L/sec	Pa.L/sec	0.13328
molecules/sec	atm.cc/sec	3.7219 x 10^-20
molecules/sec	Pa.L/sec	3.7701 x 10^-18
molecules/sec	torr.L/sec	2.8287 x 10^-20
molecules/sec	watt	3.7701 x 10^-21
Pa.L/sec	atm.cc/sec	9.872 x 10^-3
Pa.L/sec	molecules/sec	2.652 x 10¹⁷
Pa.L/sec	Pa.m³/hr	3.6
Pa.L/sec	torr.L/sec	7.5028 x 10^-3
Pa.L/sec	watt	10^-3
torr.L/sec	atm.cc/sec	1.31579
torr.L/sec	watt	0.13328
torr.L/sec	molecules/sec	3.5352 x 10¹⁹
torr.L/sec	Pa.L/sec	133.28
watt	atm.cc/sec	9.859
watt	molecules/sec	2.5 x 10²⁰
watt	Pa.L/sec	1000
watt	torr.L/sec	7.503

Converting Outgassing Units

OUTGASSING
To Convert	Into	Multiply
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/m²	1.3328
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/m²	1 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/m²	1
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/m²	1333.2
W/m²	micron.L/(cm².sec)	0.75
W/m²	Pa.L/(m².sec)	1000
W/m²	Pa.m³/(m².sec)	1
W/m²	torr.L/(cm².sec)	7.50 x 10^-4

Converting Weights and Measure Units

WEIGHTS & MEASURES
To Convert	Into	Multiply
ampere-turn	gilbert	1.257
ampere-turn/cm	ampere-turn/in	2.54
ampere-turn/in	gilbert/cm	0.495
ampere-turn/in	ampere-turn/cm	0.3937
ampere/cm²	ampere/in²	6.452
angstrom	microinch	0.00393
angstrom	millimicron	0.1
angstrom	cm	10^-8
angstrom	nanometer	0.1
angstrom	micron	10^-4
b/mil ft	grams/cm³	2.306 x 10⁶
Btu	joule	1054
Btu	kilowatt-hour	2.929 x 10^-4
Btu	ft-lb	777.6
Btu/minute	watt	17.57
calorie (kg)	joule	4184
calorie (kg)	Btu	3.968
calorie (kg)	horsepower hr.	1.558 x 10^-3
calorie (kg)	ft-lb	3086
calories (kg)	kilowatt-hour	1.162 x 10^-3
WEIGHTS & MEASURES
To Convert	Into	Multiply
circular mil	cm²	5.067 x 10^-6
circular mil	in²	7.854 x 10^-7
circular mil	sq mil	0.7854
cm	mil	393.7
cm	inch	0.3937
cm	angstrom	10⁸
cm²	ft²	1.076 x 10^-3
cm²	circular mil	1.974 x 10⁵
cm²	in²	0.155
cm³	gallon	2.642 x 10^-4
cm³	in³	6.102 x 10^-2
cm³	quarts (liquid)	1.057 x 10^-3
cm³	liter	10^-3
cm³	ft³	3.531 x 10^-5
cm³	pints (liquid)	2.113 x 10^-3
coulombs/in²	coulombs/cm²	0.155
degree (angle)	minute	60
degree (angle)	second	3600
degree (angle)	radian	0.01745
degree/sec	radian/sec	0.01745
WEIGHTS & MEASURES
To Convert	Into	Multiply
degree/sec	revolution/sec	0.002778
degree/sec	rpm	0.1667
dyne	pound	2.248 x 10^-6
dyne	gram	1.020 x 10^-3
dynes/cm²	bar	1 x 10^-6
erg	dyne-cm	1
erg	kg-meter	1.020 x 10^-8
erg	gram-cm	1.020 x 10^-3
erg	ft-lb	7.376 x 10^-8
erg	kg-calorie	2.390 x 10^-11
erg	joule	10^-7
erg	Btu	9.486 x 10^-11
ergs/sec	Btu/min	5.691 x 10^-9
ergs/sec	kilowatt	10^-10
ergs/sec	ft-lb/min	4.42 x 10^-6
feet	cm	30.48
feet	meter	0.3048
ft-lb	meter-kilogram	0.1383
ft-lb	cm-gram	13.826
ft-lb	cm-dyne	1.356 x 10⁷
WEIGHTS & MEASURES
To Convert	Into	Multiply
ft²	in²	144
ft²	m²	0.0929
ft²	cm²	929.0
ft³	lb. water	62.4
ft³	liter	28.32
ft³	pint (liquid)	59.84
ft³	cm³	2.832 x 10⁴
ft³	in³	1728
ft³	m³	0.02832
ft³	quart (liquid)	29.92
ft³	gallon	7.481
ft³	yd³	0.03704
ft³/min	gallon/sec	0.1247
ft³/min	cm³/sec	471.9
ft³/min	liter/sec	0.4719
gallon	quart (liquid)	4
gallon	liter	3.785
gallon	cm³	3785
gallon	pint (liquid)	8
gallon	ft³	0.1337
WEIGHTS & MEASURES
To Convert	Into	Multiply
gallon	lb. water	8.34
gallon	in³	231
gallon	m³	3.785 x 10^-3
gallon/min	liter/sec	0.064
gallon/min	ft³/sec	2.228 x 10^-3
gauss	lines/in²	6.452
gilbert	ampere-turn	0.7958
gram	oz	0.03527
gram	dyne	980.7
gram	lb	2.205 x 10^-3
gram-calorie	Btu	3.968 x 10^-3
gram-cm	kg-meter	10^-5
gram-cm	joule	9.807 x 10^-5
gram-cm	ft-lb	7.233 x 10^-5
gram-cm	erg	980.7
gram-cm	Btu	9.302 x 10^-8
gram-cm	kg-calorie	2.344 x 10^-8
gram/cm	lb/in	5.6 x 10^-3
gram/cm³	lb/circular mil ft	3.405 x 10^-7
gram/cm³	lb/in³	0.03613
WEIGHTS & MEASURES
To Convert	Into	Multiply
gram/cm³	lb/ft³	62.43
horsepower	horsepower (metric)	1.014
horsepower	watt	745.7
in²	ft²	6.944 x 10^-3
in²	cm²	6.452
in²	sq mil	10⁶
in²	mm²	645.2
in²	circular mil	1.273 x 10⁶
in³	pint (liquid)	0.0346322
in³	quart (liquid)	0.01732
in³	liter	1.639 x 10^-2
in³	gallon	4.329 x 10^-3
in³	m³	1.639 x 10^-5
in³	ft³	5.787 x 10^-4
in³	cm³	16.39
inch	angstrom	2.54 x 10⁸
inch	cm	2.54
joule	watt-hour	2.778 x 10^-4
joule	kg-meter	0.1020
joule	kg-calorie	2.390 x 10^-4
WEIGHTS & MEASURES
To Convert	Into	Multiply
joule	ft-lb	0.7377
joule	erg	10⁷
joule	Btu	9.486 x 10^-4
kilogram	tons (short)	1.102 x 10^-3
kilogram	lb	2.2046
kilogram (force)	dyne	980,665
kilogram-meter	kilowatt-hour	2.724 x 10^-6
kiloline	maxwell	10³
kilometer	mile	0.6214
kilometer	feet	3281
kilowatt	ft-lb/sec	737.6