MSA Sirius Mode D'emploi page 85

Gases with very high response Factors (RF):
The Sirius PID is a very versatile solution for monitoring many different
gases and vapors. In addition to the pre-programmed list provided in
the Sirius instrument, users can determine response factors for many
other compounds (see Section 7). The maximum response factor value
that will be accepted by the Sirius instrument is 39.99. Following the
procedure in Section 7, if a response factor of greater than 39.99 is
experimentally determined, the user must use the next higher energy
lamp (9.6, 10.6, or 11.7 eV) to monitor that compound. If a response
factor of greater than 39.99 is experimentally determined when using
the 11.7 eV lamp, the compound of interest has an ionization potential
too high to be detected reliably using the Sirius instrument.
Use the correct bulb when determining the response factor.
Failure to apply the appropriate response factors can result
in inaccurate readings, and serious injury or death can
occur.
Contact MSA Customer Service at 1-800-MSA-2222 with any question
regarding the above information.
These additional response factors were determined by MSA Chemists
using the Sirius Multigas Detector. The listing consists of response
factors for several common industrial chemicals that are not
preprogrammed into the instrument. Using your IBM compatible PC with
the Data Logging Software and Data Docking Module, you can add a
response factor from this list to the monitor's internal gas table. Consult
the Data Logging Software User's Manual for specific instruction.
MSA is continually developing new Response Factors; contact MSA if
your compound of interest is not listed.
Table 7-12. Known Interference Data for listed VOCs
CHEMICAL CONCENTRATION
ethylene oxide 2297 ppm
arsine 186 ppm
phosphine 303 ppm
propylene 151.6 ppm
ethylene 101 ppm
methanol 994 ppm
7-14
" WARNING
"
SENSOR CHANNEL
LEL O2 H2S CO
43 (5)
176 (5)
172 (5)
19 (5)
76 (5)
*