BAT Device Technology & Operation Principles 5

Question 1

Why must an operator perform two separate acceptable breath tests during an evidential breath alcohol testing sequence?

Accepted Answer

To provide a duplicate determination confirming the first result and detect any anomalous readings between the two tests

Answer

Duplicate breath specimens serve as an internal quality check; if the two results agree within the acceptable range (typically 0.02 g/210L), confidence in the result is established, while a large discrepancy prompts investigation.

Question 2

On a device that uses both IR and electrochemical (fuel cell) detection, what happens when the two sensors produce substantially different readings?

Accepted Answer

The device flags the result as invalid or 'out of tolerance' because the discrepancy suggests an interferent or instrument fault

Answer

Dual-sensor instruments compare IR and fuel cell results; a significant difference indicates the presence of an interferent or a sensor malfunction, and the instrument will flag or void the test.

Question 3

What is the purpose of the 'purge' cycle that occurs between tests on an evidential breath analyzer?

Accepted Answer

To flush residual breath alcohol from the sample chamber with ambient air, preventing carryover into subsequent tests

Answer

The purge cycle draws ambient (room) air through the sample chamber to remove any residual ethanol vapor from the previous sample, ensuring a clean chamber for the next blank and subject test.

Question 4

An operator notices the simulator temperature reading on an Intoxilyzer 8000 is 33.2°C instead of the required 34.0 ± 0.2°C. What is the appropriate response?

Accepted Answer

Do not use the simulator; the temperature is out of specification and would invalidate the calibration check

Answer

A simulator temperature outside the ±0.2°C tolerance of 34°C produces a vapor concentration that does not match the certified standard value, making any calibration check performed at that temperature invalid.

Question 5

Which of the following interferents is most commonly associated with producing a false-positive result on older single-wavelength IR breath analyzers?

Accepted Answer

Methyl ethyl ketone (MEK) from occupational solvent exposure

Answer

Methyl ethyl ketone (MEK) absorbs IR radiation at wavelengths overlapping ethanol's primary absorption band and has been documented to produce false-positive readings on single-wavelength instruments.

(BAT) Breath Alcohol Technician Certified Practice Test

(BAT) Breath Alcohol Technician Certified Practice Test

BAT Device Technology & Operation Principles 5