Teledyne 400E Instruction Manual page 222

THEORY OF OPERATION
Aromatic Hydrocarbons
While the instrument effectively rejected interference from meta-xylene, it should
be noted that there are a very large number of volatile aromatic hydrocarbons that
could potentially interfere with ozone detection. This is particularly true of
hydrocarbons with higher molecular weights. If the Model 400A is installed in an
environment where high aromatic hydrocarbon concentrations are suspected,
specific tests should be conducted to reveal the amount of interference these
compounds may be causing.
Mercury Vapor
Mercury Vapor absorbs radiation in the 254nm wavelength so efficiently that its
presence, even in small amounts, will reduce the intensity of UV light to almost
zero during both the Measurement and Reference Phases rendering the analyzer
useless for detecting O
If the Model 400E is installed in an environment where the presence of Mercury
vapor is suspected, specific steps MUST be taken to remove the Mercury Vapor
from the Sample Gas before it enters the analyzer.
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Model 400E Ozone Analyzer
Instruction Manual
P/N 04316 Rev: B