ENMET ISA-44-2OD User Manual
Page 12
ENMET Corporation
ISA-44-2-OD
8
3.2 Sensor Location
Gases have different densities. Some are heavier than air and concentrate at the bottom of a space. Some are lighter
than air and gather at the top. Consider the density of the gas you want the sensor to detect when you install the
sensor. As a guide, consult the gas descriptions below.
Table 1: Heavier than Air
Gas
Sensor Location
Bottled LP (liquefied petroleum)
Propane
Butane
Gasoline
Trichloroethylene
Vaporized hydrocarbons
Hydrogen sulfide
Interior wall; 18-24" from floor.
§
D
O
N
OT
locate directly above or beside gas
appliances (ovens, heaters).
§
Avoid locating anywhere near a vent or window or
near an outside doorway.
Table 2: Lighter than Air
Gas
Sensor Location
Natural gas (methane)
Ammonia
Hydrogen
Near ceiling.
§
D
O
N
OT
locate directly above appliances where it is
subject to direct exposure to heat or steam.
Table 3: Same Density as Air
Gas
Sensor Location
Carbon Monoxide
4-6 feet above the (generally uniform) floor.
§
D
O
N
OT
locate in direct air currents of windows, doors, or vents.
Oxygen
Oxygen deficiency is usually caused by a gas that displaces the air in a space. The oxygen sensor should be located to
quickly detect the displacement of air by the gas. If a heavier than-air gas is involved in the application, locate the
sensor low in the space being monitored. Conversely, if a lighter-than air gas is involved, locate the sensor high in the
space. If there is doubt, call ENMET we will help you locate the sensor correctly.
Figure 6: Oxygen Cell Enclosure
Oxygen Sensor
Oxygen Sensor
Enclosure Bottom
Oxygen Sensor
Enclosure cover
(Cut away view)
Remove Shoring
Clip or Spring
O2 Cell Circuit Board
w/cell installed on circuit side
Orange Wire
Green Wire
Oxygen Cell
Bottom View