Ulvac CRYO-U Series, Instruction Manual, Page: 15 / 106

ULVAC CRYOGENICS INCORPORATED S-3
For handling toxic gases , specific safety measures to the gas may have to be taken as
well as the safety precautions for flammable or explosive gases. For example, purge of
pump or dilution of exhaust duct with inert gas corresponds to it.
opump operation according to an equipment and process where it
ill be adopted.
Table 1 Combu of major gases
(Volume percen ge against air)
Gas
Molecular
Weight
0
℃
Boiling
Point
Combustion Detonation
The customer oneself must execute the appropriate safety measure planning for
managing the cry
w
stion range and detonation range
ta
Specific
Gravity
, 1atm
K
Range
Vol. %
Range
Vol. %
Hydrogen
arbon C
Monoxide
12.5-74.0
4.3-45.0
18.3- 59
Hydrogen
Sulfide
Silane*
Arsine*
Phosphine*
Diborane*
Ammonium
Methane
Ethane
Propane
Etylene
Acetylene
2 4
C
2
H
2
26.04 0.907 198.2 2.5-100 4.2- 50
H
2
CO
H
2
S
SiH
4
AsH
3
PH
3
B H
6 2
NH
3
CH
4
C
2
H
6
C
3
H
8
C H
2.016
28.01
34.08
32.14
77.94
34.00
27.67
17.03
16.04
30.07
44.10
28.05
0.070
0.970
1.190
1.107
2.692
1.146
0.955
0.590
0.555
1.040
1.550
0.978
20.3
81.7
213.6
161.2
210.7
185.5
180.7
239.8
111.6
184.6
231.1
169.5
4.0-75.0
0.8-98
0.8-98
1.3-98
0.8-98
15-28
5.3-14
3.0-12.5
2.2-9.5
3.1-32
(*): Hikaru Harada; "Handotai-gas Anzen-ka Souran 1st Edition" (The 1st edition of Semiconductor
gas safing comprehensive manual) published by Science Forum Inc. 1984
The high pressure gas safety institute of Japan; "Koatsu-gas Kogyo Gijy Except (*): utu" (High pressure gas
industrial tech
Tabl
mix am
nge Detonation Range
nology) published by Kyoritsu Shuppan Co., Ltd. 1977
e 2 Combustion range and detonation range of
ture of oxygen and fl mable gas
Gas Combustion Ra
( Vol. %) (Vol. %)
Hydrogen
Acetylene
oxide
2.3 - 94.5
15.5 - 94
Methane
Propane
Carbon Mon
Ammonium
15 - 79 25.4 - 75
4 - 94
5.1 - 61
2.3 - 55
15 - 90
3.5 - 93
-
3.7 - 37
38 - 90
The high pressure gas safety institute of Japan; "Koatsu-gas Kogyo Gijyutu" (High pressure gas industrial
chnology) published by Kyoritsu Shuppan Co., Ltd. 1977 te