1. FTIR spectrometer system (source,
interferometer, sample absorption cell, and
detector) configured with absorption. A
minimum instrumental linewidth (MIL) 2 cm-1
or lower is recommended.
NOTE:A lower or higher MIL may be required
or suitable for specific gas matrices. Choose
internal absorption cell materials to minimize
surface/analyte interactions.
2. Computer system with hardware, software,
and required reference spectra for
acquisition, storage, and analysis of sample
spectra. (A data backup system is
recommended.)
3. Sampling pump, 0.1 to 10 L/min, with
appropriate particulate filters.
4. Non-reactive gas regulators and sample
tubing.
5. Rotameters or other devices, 20% accuracy,
for measuring flow rates of sample and
calibration gases.
6. Temperature measurement and/or control
equipment for all sam pling system elem ents
and IR absorption cell.
NOTE:Temperature control equipment
required if ambient temp. 30 °C.
7. Pressure gauge for measuring absolute gas
pressure in absorption cell, 5% accuracy at
one atmosphere (760 mm Hg) absolute
pressure.
8. For system tests (but not for normal
operation): Vacuum pump and gauge
capable of 100 mm Hg abs. pressure; midinfrared
attenuating filters (50% and 25%);
impinger