Chemgard

TM

Infrared Gas Monitor

E VERY L IFE H AS A P URPOSE…

Chemgard Overview

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What is Photoacoustic Infrared and how does it compare with other technologies:

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Review of traditional IR PIR Theory –What happens when light meets sound?

Comparison w/ traditional IR Electrochemical Sensors Flame Ionization Detectors Gas Chromatography Solid State Sensors

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Chemgard Markets & Applications

Photoacoustic Infrared Gas Detection Technology

 To better understand the advantages of Photoacoustic Infrared Technology, we will briefly compare it to the older, more commonly used Absorptive Infrared Technology. 

How Does It Differ?

Infrared Detection Methodology

 Both absorptive and photoacoustic techniques utilize infrared energy of a selective wavelength.  Majority of gases absorb infrared energy of various wavelengths.  The wavelength selected for use in detection is determined by the gas in use and its specific characteristics.

Infrared Technology

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Red

is representative of a typical gas absorption characteristic.

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Yellow i

s an infrared wavelength used to detect this specific gas.

Absorptive Technique

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All absorptive infrared detection methods differ from manufacturer-to-manufacturer. However, the basic principal remains the same.

    Sample and Reference measurements must be taken. The Sample cell is exposed to the gas to be detected. The Reference cell is either isolated from the gas to be detected or infrared energy outside the absorptive wavelength characteristics of the gas to be detected is used.

The two measurements are compared. If they are equal, the instrument will indicate zero (0).

Absorptive Technique

 When the gas to be detected is present, it absorbs some portion of the Sample infrared energy.

 The Reference infrared energy is unaffected by the gas to be detected.  The change in ratio of the Sample and Reference detectors is the actual concentration of gas present.

Photoacoustic Infrared Technology

  Has been in use since the 1960’S MSA –10 Years of experience in PIR gas monitors  Has replaced many traditional infrared analyzers as well as other sensing technologies

Advanced Technology

Photoacoustic Infrared sensing technology differs from all other available detection techniques on the market.

 It has Two distinct advantages:  The ability to sense a leak as low as in the PPB level for some applications.

 The ability to operate long periods of time without adjustment or zero drift, a common problem with all other technologies in use today.

Basic PIR Cell Assembly

Photoacoustic IR Optical Bench

       IR source - wire filament emitting multiple wavelengths of light Chopper (not shown) - used to setup modulation Optical filters  provide sensitivity and selectivity for a given gas  selected for specific application Optical block - volume can be changed for specific ranges Detector-high sensitivity microphone Solenoid valves - sample inlet and outlet provide seal during photoacoustic gas detection Heater and thermostat - temperature control critical for low PPM or PPB detection

 Sample Gas Enters the Cell…..

Photoacoustic Infrared Technology

Toxic Gas Sensors

Electrochemical Sensors

Flame Ionization Detectors

Gas Chromatographs

Solid State Sensors

Chemical Tape Technology

Technology Comparison

Gas Detection Comparison

Chemgard Applications

 Applications include:  CO, CO2, cleaning agents, solvents, heat transfer fluids & many other common industrial chemicals  Photoacoustic Infrared Gas Detection used in:  plastics, paint, automotive, pharmaceutical, semiconductor, rubber & other general chemical industries

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3M Air Products BASF Chrysler Dow Chemical Co Dupont GE Plastics Kimberly Clark LA Municipal Authority Miller Brewing Mitsubishi Praxair Toshiba Walt Disney Xerox Some Chemgard Customers

The Chemgard Advantage

The Chemgard Advantage

The Chemgard Advantage

The Chemgard Advantage

Chemgard Industries

Petrochemical Industries

Plastics & Paint Industry

Agricultural Industry

Rubber Industry

Medical & Pharmaceutical Industry

Semiconductor Industry

Automotive Industry

The Chemgard Advantage

 Utilizes Photoacoustic Infrared Gas Detection Technology  Can detect a wide range of industrial compounds  Detection of Percent, PPM or in some cases PPB levels  High Sensitivity and Selectivity to Gas of Interest