Heath Consultants Odorator - Manual (Page 20)

Appendix C
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Appendix C
ODORATOR Use at Elevation
The ODORATOR works by allowing a metered amount of sample gas to
mix with a fixed amount of air and the mixture is then tested by a user for
odorant detection. The internal components of the ODORATOR are very
stable over changes in elevation. The air that is mixed, however, thins out
with increasing elevation and must be accounted for. An elevation change
of 3000 feet from the calibration can produce reading discrepancies of nearly
10 % which may be corrected. It is recommended that the ODORATOR
readings be corrected whenever the elevation change from calibration is
1000 feet or more. The calibration elevation may be found on the exhaust
port label.
A correction chart with accompanying usage directions has been developed.
The chart provides corrections for both increased and decreased elevations.
Most instruments will be used at elevations higher than their calibration
elevation. ODORATORS calibrated at the factory have a calibration el-
evation of about 50 feet. Many gas utilities send their ODORATORS to
the Heath factory for periodic calibration, hence most instruments will be
used at elevations higher than their calibration elevation. ODORATORS
calibrated at one elevation and then used at a higher elevation will make the
most use of this chart. An ODORATOR calibrated and used within 1000
feet of the same elevation will use the respective correction chart found on
the instrument.
The elevation correction chart is based on a normal atmosphere. Abnor-
mal atmospheres, as caused by extreme weather conditions, can affect
the measurements and safe use of the ODORATOR and operation is not
recommended. Usage instructions are included with the chart but use the
difference in elevation between the working or measurement elevation and
the calibration elevation to select the respective correction value versus the
ODORATOR’S reading.