Performance

The European Standard EN 13725:2003 states:

The quality requirements for the performance of the analytical method as a whole and of equipment used to present the sample to the assessor are the core of this standard.

Compliance of the dilution equipment used by a laboratory to the instrumental quality requirements shall be tested and demonstrated regularly. The appropriate calibration frequency shall be based on the performance history of the equipment, but shall be at least once a year.

Compliance testing shall involve the full dilution range of the instrument, with at least two points for each decade of dilution factor Z. For instruments with discrete dilution settings, every setting shall be tested for compliance.

6.5.5 Calibration procedure

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Five test results shall be collected for every dilution setting,. Between measurement for each test result the controls of the dilution instrument, if this is applicable, are set to another setting. Each test result yi,d shall consist of at least ten observations oj with a sampling frequency no less than once in every 10 s. This is relevant for the determination of instability. The lag time of the monitor, including the sampling system, shall not be more than one cycle of the sampling frequency. To obtain one test result, at least 10 observations shall be recorded.

Using the procedure described above, both the figure and the table show the instability and the accuracy of the DynaScent olfactometer over 17 dilution steps. Performance quality requirements are:

Accuracy < 0.20 (20%) for each dilution step

Instability < 0.05 (5%) for each dilution step

DynaScent performance using mass flow

The instrumental performance of the DynaScent has been discussed in the paper "Development of the Next Generation Dynamic Olfactometer – Dynascent".