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Use of Wet-bath Simulator in Winter Cold Temperatures

Updated: Sep 27, 2022


To cross-examine a CFS scientist on use of Guth 2100 wet-bath simulator under Canadian cold operating conditions

To build a case for O'Connor production of contemporaneous documentation by the QTs who obtained the groups of low cal. checks in the breath truck in winter.

During Direct Examination, the CFS expert had suggested in response to the Crown's request for the simplest explanation for anomalous low cal. checks, that the door being left open on the breath truck in winter could cause repeated cal. checks below 90. The purpose of this cross-examination was to suggest that if this was the case, then QTs of this police service are not using the simulator in accordance with manufacturer's recommendations for minimum ambient operating temperatures.

Page 15 UL Symbols and Warnings, Triangle with "!": Temperatures 5 degrees C to 33 degrees C
Excerpt from Guth Laboratories Inc. Model 2100 Simulator Operation Manual, Harrisburg PA Price 5.00 Note warning at the top: Triangle with "!"

Now, in addition to that, page 15. A. Okay. Q. With respect to operating conditions for the simulator. A. Yes. Q. Supposed to be used at a temperature of 5 degrees Celsius to 33 degrees Celsius in terms of ambient temperature. A. Yes. Q. Right? A. Correct. That’s what it reads. Q. So, if an operator is using the simulator in temperatures below 5 degrees Celsius, then they’re not using the simulator properly. A. That would be correct. I’m not aware of anybody who does breath testing outside of an enclosed environment at wintertime. Q. So, we should expect the simulator in this case, if it’s operating in accordance with manufacturer’s specifications, to be maintaining a temperature of 34.00 degrees plus or minus .05 degrees, although the Ontario expectation is .2 degrees Celsius. A. And Canada, too. Q. So, I don’t understand why we would be

considering that the temperature of the simulator would be dropping. Why would we be – I would call it speculating – why we would be hypothesizing that the simulator temperature would be dropping when somebody opened the door to a breath truck. A. Well, it’s the room air that’s going to change. Right? So, if you – again, I don’t know what the inside temperature of a BAT-mobile, the Breath Alcohol Truck – sorry. Right? BAT truck, but you’d have to ask somebody who works for [the local] Police whether they control that and or monitor it. I don’t know. I would expect that it would be within the normal operating temperatures, within this guideline here. If it was above or below, that would simply require the simulator to either turn on, if the room was cold, and to keep and maintain that temperature, ‘cause it’s a – it’s a glass vessel. Q. Yes. A. Right? The solution is placed in a glass vessel, 500 millilitres, and then there’s a cap which contains all the electronics. Q. Yes. A. Both of those, of course, can be subject to outside temperatures. Q. Yes. A. And the outside temperature would determine how often the heater comes on. Q. Yes. A. So, think of this as like a low wattage kettle. It essentially warms the water to 34 degrees Celsius and it has a thermostat, the same way you have a thermostat in your house, that you program. And so, what happens is, is that when the temperature in your house changes, the furnace comes on, or shuts off, depending on whether it reaches that

temperature, and then it’ll come back on when that temperature drops. And so, the same situation would occur with respect to a simulator, that the heater would come on and off depending on what and how often that solution needs to be heated in order to maintain that temperature at 34 degrees Celsius. Q. And I suppose if the simulator is not being used the way that it’s supposed to be used, i.e. in temperature conditions of 0 or 1 or 2 or 3 degrees Celsius, that could be a possible cause of low cal-checks. A. Sorry, what were the temperatures that you.... Q. Zero degrees Celsius, one degree Celsius, two degrees Celsius, three degrees Celsius. That could be a cause of low – a possible cause. I’m not asking you to speculate. I’m just considering the range of possibilities. Then the instrument may not be operating within its normal operating temperature range. A. Correct, yes. Q. And we shouldn’t – we shouldn’t expect it to be doing what it’s supposed to do because it’s outside of its normal operating range. A. Correct. However, even then, I would expect that you might have low calibration checks. It just would mean that the heater would be on longer in order to try and maintain that temperature. It would have – so the simulator would have more difficulty maintaining the temperature exactly at 34.00 degrees Celsius... Q. So, if we.... A. – in a – in a colder environment like that, compared to say, room temperature. Q. So, if we have a group of low calibration checks, a possible cause could be the simulator is not being

used in accordance with its proper operating conditions. A. It may have some affect on the temperature, yes. Q. Right. And.... A. How much? I couldn’t begin to speculate.

[Note: Should be follow-up cross-examination on simulator heater response time.]

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