(1) Density of the gas to be detected
(2) Most probable leak sources within the industrial process
(3) Ventilation or prevailing wind conditions
(4) Personnel exposure
(5) Maintenance access
Density
- Placement of sensors relative to the density of the target gas is such that sensors for the detection of
heavier than air gases should be located within 4 feet of grade as these heavy gases will tend to settle in low lying
areas. For gases lighter than air, sensor placement should be 4-8 feet above grade in open areas or in pitched areas
of enclosed spaces.
Leak Sources
- Most probable leak sources within an industrial process include f langes, valves, and tubing connec-
tions of the sealed type where seals may either fail or wear. Other leak sources are best determined by facility engi-
neers with experience in similar processes.
Ventilation
- Normal ventilation or prevailing wind conditions can dictate eff icient location of gas sensors in a
manner where the migration of gas clouds is quickly detected.
Personnel Exposure
- The undetected migration of gas clouds should not be allowed to approach concentrated per-
sonnel areas such as control rooms, maintenance or warehouse buildings. A more general and applicable thought
toward selecting sensor location is combining leak source and perimeter protection in the best possible configuration.
Maintenance Access
Consideration should be given to easy access by maintenance personnel as well as the consequences of close prox-
imity to contaminants that may foul the sensor prematurely.
Detcon Model TP-524C Hydrogen Sulfide Sensor
PG.8
EYS
Seal
Fitting
Drain
“T”
Plug any unused ports.
Figure #1
4 3/4"
5 1/4"
3/4" NPT
Rain
Shield
2"
2 1/8"
1/4" Dia.
Mounting Holes
Grounding Lug
Cover
Set
Screw
5 1/2"
7"
Figure #2
