Appendix C Response Factors - Thermo Scientific TVA2020 Instruction Manual

Response
Thermo Fisher Scientific
Appendix C
Response Factors
The TVA2020 is a portable vapor analyzer for gas survey monitoring. Each
unit is factory calibrated with Methane (in the case of the FID) and
Factors
Isobutylene (in the case of the PID). However, both detectors respond to
many different compounds with differing levels of sensitivity. In order to
adjust the analyzer reading from "ppm of Methane" or "ppm of
Isobutylene" to ppm of the compound of interest, a correction factor must
be applied to the reading. This correction factor is also known as a
"Response Factor".
Response factors can be expressed in several different formats. When you
acquire a response factor from any source, it is important that you
understand the format in which the response factor is expressed so that it
can be applied properly. Following are the two most common response
factor formats:
1. Response Factor Multiplier
The response factor multiplier is the most commonly used and most
widely recognized response factor format. This type of response factor
is calculated by dividing the actual concentration of a compound
introduced to the analyzer by the detector response.
Response
For example, if 100 ppm of a compound produces a 50 ppm FID
reading on an analyzer calibrated with methane, then the FID response
factor for that compound would be 2.00 (100 divided by 50).
When a using a response factor multiplier to correct a TVA reading,
simply multiply the analyzer measured response by the response factor.
As in the example given above, if a 50 ppm reading is achieved,
multiply 50 times 2.00 to get the actual concentration (100 ppm).
Response.
Response Factor Mulitplier is what the TVA2020 uses.
Actual

Factor Multiplier
Measured
Concentrat ion
Response
TVA2020 Instruction Manual C-1