Max. error
The maximum measurement error provided by the device during operation, in other words, the largest deviation from the actual result that may occur during measurements. For example, if the error is claimed at the level of 0.1 ‰, and the measurement result is 0.5 ‰, then the actual amount of alcohol in the blood will be from 0.4 ‰ to 0.6 ‰.
In the most advanced models, this parameter is
0.05 ‰ or less ; values of
0.06 – 0.1 ‰ correspond to the average level,
more than 0.1 ‰ — low accuracy. The lower the error, the more accurate the device, the more reliable its readings. On the other hand, high accuracy has a corresponding effect on the price. Therefore, when choosing according to this criterion, it is worth considering what exactly a breathalyzer is needed for and how important measurement accuracy is for it. In particular, for devices used by the traffic police, there are accuracy requirements that are expressly specified in regulatory documents.
Warm-up time
The warm-up time of the breathalyzer to the working state, in other words, the time that must pass after switching on or after the end of the previous measurement before the device can be used.
The fastest modern breathalyzers warm up in 5 – 6 seconds, time
up to 20 seconds is considered quite good; in
slower models, this time can be up to a minute. At the same time, it makes sense to specifically look for a device with a short warm-up time only in cases where it is needed for streaming checks and high speed is crucial. And if the device is purchased for individual use with measurements a maximum of 2 – 3 times a day — you can not pay much attention to this parameter: waiting even a few tens of seconds is most often not a problem.
Anti-deception
A function that allows the breathalyzer to automatically control the correctness of the measurement procedure. To do this, the device analyzes the volume of actually exhaled air, and if this volume is not enough for effective analysis, it reports that the measurement needs to be repeated. As the name implies, the main purpose of anti-
cheating is to prevent measurement manipulation, when the test person tries to artificially lower the readings by “blowing out” an insufficient amount of air. Although, of course, this function will be useful if the user violates the procedure unintentionally.
Automatic shutdown
Devices with this function are able to
automatically turn off if the user has not performed any actions for a certain time after the last measurement. This saves battery power, eliminates the need to manually turn off the power, and can be a good insurance against forgetfulness. The shutdown time is usually from several tens of seconds to several minutes; in some models, it can be set at your discretion.
Operating temperature
The range of air temperatures at which the breathalyzer is able to work correctly. Note that if the device goes beyond this range, the device will not necessarily fail, but there is no need to talk about the accuracy of measurements in such a situation. This parameter is especially important for models with semiconductor sensors (see "Sensor") — the correct operation of such sensors is highly dependent on the ambient temperature. It is best to use such a device at a temperature corresponding to approximately the middle of the allowable range — in this case, the error will be minimal.
The most cold-resistant modern breathalyzers are capable of operating
at sub-zero temperatures, the most resistant to heat — at temperatures of
+45 ... +50 °C.
