Breathing Gas Analyser: Protea Model BG100

For Fighter Pilots * Professional Divers * Fire Fighters * Hospital Patients



Protea's Breathing Gases Analyser System detects and measures impurities in the bottled breathing gases used by pilots, divers, fire-fighters and hospital patients. It meets current standards such as USAF MIL-O-27210, NATO STANAG 3545 and MoD 68-284.

Powerful analyser control and analysis software is used. A convenient sampling system is also supplied which regulates the flow of sample gas to the analyser, allows easy change-over between samples, and maximises analysis accuracy. Analysis results are presented to the user in standard and customised report formats within a few minutes and all collected spectra and reports are stored with a unique date/time/sample identification stamp.

The system uses an ABB Bomem Inc FTIR analyser. To calibrate additional gases, a convenient septum interface is provided on the sample cell for injecting measured amounts of reference gases.



FEATURES AND BENEFITS OF THE BG100:

THE SAMPLING SYSTEM

The sampling methodology used with the BG100 is shown in the opposite figure. The sampling system is used to prepare the sampling cell on the FTIR analyser for a reference by purging with dry nitrogen. It is also used to purge the gas cell with sample. To verify system performance, or to perform additional calibrations, the sampling system can also prepare the cell for a gas or volatile liquid injection. The cell is first purged with nitrogen, then partially evacuated just prior to the injection. After the sample is injected into the gas cell using a septum connection, the sampling system restores the gas cell pressure using nitrogen. Due to the low concentrations required for the determination of trace gases, the use of syringes to inject small volumes of a gas or liquid proves very convenient.

THE SOFTWARE

Protea has developed a user interface and custom report forms specific for the Breathing Gases application which operate within Grams. Grams is a powerful tool which allows the user to perform spectral analysis. Protea's user interface simplifies and automates the use of Grams - to control the FTIR analyser, to operate the sampling system, to analyse and save spectra, and to prepare customised reports. Operation of these through the user interface is quite simple. However, the user has access to the full power of Grams if needed.

Note: Grams LT is supplied as standard, and is a product of Thermo Electron Corporation

SPECIFICATIONS

The following specifications apply for the analysis of breathing oxygen for fighter pilots in accordance with Military Standard MIL-O-27210. The gas components measured are given in the table below, together with their Limit Of Detection (LOD) and procurement limits as required by the Standard. For maximum accuracy, Protea has calibrated each of the 11 components over an 11-point range up to the procurement limit. An advanced mathematical calibration model based on partial least squares (PLS) has been compiled using all such data points. The concentrations of Freon 12, 22, and 113 are reported separately in the standard report, as are solvents 1,1,1 Trichloroethane and Trichloroethylene. The measurement time is less than 2 minutes using an MCT detector. The concentration precision is generally better than ±10% in the calibrated range for each component. This includes the effects of interference by other components. The analyser can be calibrated for a wide variety of additional trace contaminants in breathing air. It can also be used for other gas analysis applications.

Gases Measured for Military Standard MIL-O-27210