Air Products GASGUARD TE10, Installation, Operation And Maintenance Manual

Page: 76 / 196

GASGUARD
®
TE10 Distribution System Manual
Air Products and Chemicals, Inc. Page 3 - 10
The tables below list the exhaust requirement for the GASGUARD 500VMB
enclosure to meet UFC and NFPA code requirements.
Table 1
Minimum Exhaust Requirements for
GASGUARD 500 VMB Enclosures Containing Silane
ACCESS HATCH CLOSED [2] ACCESS HATCH OPEN [3]
Enclosure
Size [1]
exhaust
flow
(cfm)
static
pressure
(in H20)
velocity
pressure
(in H20)
exhaust
flow
(m3/m)
static
pressure
(Pa)
velocity
pressure
(Pa)
exhaust
flow
(cfm)
velocity
pressure
(in H20)
exhaust
flow
(m3/m)
velocity
pressure
(Pa)
GG500
24” wide
375 -0.4 -0.23 10.6 -100 -57 400 -0.26 11.3 -65
GG500
30” wide
450 -0.5 -0.33 12.7 -124 -82 470 -0.36 13.3 -90
Notes : [1] All vent stack duct sizes are 6 inch (154 mm) diameter.
[2] “Access Hatch Closed” values have been measured at the exhaust stack duct and
provide a minimum air velocity of 200 feet per minute (61 meters per minute) across
cylinder connections and panel fittings.
[
3] “Access Hatch Open” values have been measured while observing a minimum
velocity of 200 feet per minute (61 meters per minute) across the access hatch
opening.
[4] These recommended values assume that a 0.25 mm [0.010 inch] diameter
restrictive flow orifice (RFO) is installed in the Silane source cylinder valve per US
Code requirement
Table 2
Exhaust Recommendations for Gasguard Equipment Containing
Gases with a TLV
≥
0.20 ppm (25% TLV > 0.050 ppm)
Notes :
[1
] ERC (Expected Release Concentration) values are taken from actual test data.
[2] ESI (Ex hau st Stack Insert) may have been specified by the customer to enhance
the readability of the exhaust pressure monitor. Refer to the system’s
Specification Sheet to determine if this option is used.
[3] These exhaust flow values are applicable to the 30 inch and 24 inch standard flow
Gasguard VMB enclosures.
[4] All standard Gasguard enclosures are sized for a 6 inch outer diameter (OD) duct
connection to the vent stack.
[5] “Access Hatch Closed” values have been measured, or calculated at the exhaust
stack duct.
[6] The actual values presented in "Access Port Open" are from experiments done on
a two-cylinder MC source system enclosure. Due to the similar design and smaller
access port of the GG500 VMB enclosure, balancing to Tables 2 and 3 will satisfy
meet or exceed UFC 80 face velocity requirements.
Maximum
ERC [1]
Exhaust
Flow
Static
Pressure
Velocity
Pressure
Exhaust
Flow
Velocity
Pressure
Average
Duct
Velocity
Minimum
Face
Velocity
Average
Face
Velocity
Baffle
ppm scfm
inches
H2O
inches
H2O
scfm
inches
H2O
fpm fpm fpm
No ESI
[2]
0.029 75 -0.5 0.05 318 0.255 1622 180 220 None
ESI < 0.029 75 -1.5 0.15 237 0.775 1210 210 236 33%
Access Port Closed Access Port Open