Simultaneous monitoring of greenhouse gases with FTIR

Among gases that affect the global environment, gases that are stable, such as carbon dioxide, methane, halogenated carbon compounds, have a considerable impact on global warming and are termed ‘greenhouse gases’. On the other hand, nitrogen compounds, sulfur compounds and volatile oxygenated carbon (VOC) gases are quite reactive and thus regarded as air pollution gases that can cause photochemical oxidation, smog and the worsening of indoor environments. Many gases used in the manufacturing processes of semiconductors are also harmful and the strict control and monitoring of these gases are required. It is important to monitor the different classes of gases with appropriate systems to study the impact on the atmospheric environment. One of the features of a newly developed program dedicated for IR gas analysis system is to be able to analyze similar multi-component compounds simultaneously by using a calculation of subtracted spectra. In addition, the Time Course Measurement software makes it possible to perform continuous monitoring of these noxious gases.

Features of the continuous quantitative analysis program for multiple components are:

• Simultaneous quantitative analysis of up to 50 components
• Continuous measurements up to 40 days at a time
• Replaceable calibration curve on an ‘as-needed’ basis
• Open-Path measurement capability

This program can be used with the VIR-9500 series as well as the FT/IR-4000/6000 series instruments. The VIR series instruments allows sample monitoring for a wide range of purposes such as outdoor or clean room applications because it can be easily moved and installed due to a small and portable size. Full vacuum FT/IR systems can provide quantitative analysis of carbon dioxide and water vapor in air with a high degree of accuracy. The gas cells in a length from 10 cm to 20 meters are available and a suitable cell can be selected depending upon the desired analytical gas concentrations.