4-9
Brooks
®
Models 5964, 5850EM
Section 4 Maintenance
Installation and Operation Manual
X-TMF-5964-5850EM-MFC-eng
Part Number: 541B121AHG
November, 2008
GAS NAME
FORMULA
SENSOR
ORIFICE
DENSITY
FACTOR
FACTOR
(kg/m
3
)
Pentane (n-Pentane)
C
5
H
12
0.212
1.605
3.222
Phosgene
COCL
2
0.504
1.881
4.418
Phosphine
PH
3
0.783
1.100
1.517
Phosphorous Pentafluoride
PF
5
0.346
2.109
5.620
Phosphorous Trifluoride
PF
3
0.495
1.770
3.906
Propane (same as CH
3
CH
2
CH
3
)
C
3
H
8
0.343
1.274
2.008
Propylene (Propene)
C
3
H
6
0.401
1.234
1.875
Rhenium Hexafluoride
ReF
6
0.230
3.279
13.41
Silane
SiH
4
0.625
1.070
1.440
Silicon Tetrachloride
SiCL
4
0.310
2.465
7.579
Silicon Tetrafluoride
SiF
4
0.395
1.931
4.648
Sulfur Dioxide
SO
2
0.728
1.529
2.858
Sulfur Hexafluoride
SF
6
0.270
2.348
6.516
Sulfur Tetrafluoride
SF
4
0.353
1.957
4.776
Sulfur Trioxide
SO
3
0.535
1.691
3.575
Sulfuryl Fluoride
SO
2
F
2
0.423
1.931
4.648
Tetrachloromethane
CCL
4
0.344
2.345
6.858
Tetrafluoroethylene (TFE)
C
2
F
4
0.361
1.905
4.526
Tetrafluorohydrazine
N
2
F
4
0.367
1.926
4.624
Trichlorofluoromethane f-11
CCL
3
F
0.374
2.244
6.281
Trichlorosilane
SiHCL
3
0.329
2.201
6.038
Trimethyloxyborane (TMB)
B(OCH
3
)
3
0.300
1.929
4.638
1,1,2-Trichloro-1,1,2-Triflouroet f-113
C
2
CL
3
F
3
0.231
2.520
7.920
Trimethylamine
(CH
3
)
3
N
0.316
1.467
2.639
Tungsten Hexafluoride
WF
6
0.227
3.264
13.28
Uranimum Hexafluoride
UF
6
0.220
3.548
15.70
Vinyl Bromide
C
2
H
3
Br
0.524
1.985
4.772
Vinyl Chloride
C
2
H
3
CL
0.542
1.492
2.788
Vinyl Fluoride
C
2
H
3
F
0.576
1.281
2.046
Water Vapor
H
2
O
0.861
0.802
0.804
Xenon
Xe
1.383
2.180
5.851
Table 4-3 Conversion Factors (Nitrogen Base) Continued
Ref. No. J-836D508 Gasdata.doc Vsn. 8.6
Example: The desired gas is 20% Helium (He) and 80% Chlorine (Cl) by
volume. The desired full scale flow rate of the mixture is 20 slpm. Sensor
conversion factor for the mixture is:
Nitrogen equivalent flow = 20/.945 = 21.16 slpm Nitrogen
It is generally accepted that the mass flow rate derived from this equation
is only accurate to ±5%. The sensor conversion factors given in Table 4-3
are calculated based on a gas temperature of 21°C and a pressure of one
atmosphere. The specific heat of most gases is not strongly pressure, and/
or temperature, dependent. However, gas conditions that vary widely from
these reference conditions may cause an additional error due to the
change in specific heat caused by pressure and/or temperature.