Blowing
The method of blowing provided in the design of the device.
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Through the mouthpiece. Breathalyzers that need to be blown through a special mouthpiece. This use is associated with additional difficulties: for hygiene and reliable measurement, the mouthpiece must be perfectly clean. This means that if the mouthpiece is reusable, it must be sterilized before each measurement; An alternative is to use disposable mouthpieces, but this comes at an additional cost. On the other hand, this measurement method provides the greatest accuracy: only exhaled air enters the device, without additional impurities, and even with a relatively low sensor accuracy, fairly reliable readings can be achieved. And professional breathalyzers work exclusively through the mouthpiece.
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No mouthpiece. Models that do not use a mouthpiece: when measuring, just blow into the hole on the body. The main advantage of such devices is simplicity and ease of use: no need to bother with the sterilization of reusable mouthpieces or spend money on disposable ones. On the other hand, the accuracy and reliability of such models is noticeably lower than that of mouthpiece models: not only exhaled, but also ambient air enters the device, and the sensor can react not only to alcohol, but also to foreign impurities. In advanced devices, this disadvantage can be compensated by the use of high-precision sensors, but the accuracy of su
...ch models is still lower than that of mouthpieces. And most breathalyzers with this type of blowing belong to the low-cost category.Measuring range
The measurement range provided by the breathalyzer. It is indicated from the minimum level of alcohol in the blood that the device is able to detect, to the maximum.
It is worth choosing according to this parameter, taking into account the purposes for which it is planned to use the device, what levels of alcohol they will have to measure. For your convenience, you can use the following table:
— Up to 0.3 ‰ — asymptomatic degree of intoxication. There are no obvious signs of alcohol consumption, it is impossible to detect them without special means. In countries where there is no “zero per mille” rule for drivers, the blood alcohol level allowed for driving is usually within these limits (most often it is 0.2 ‰).
— 0.3 – 0.6 ‰ — a slight degree of intoxication. Some violation of concentration and coordination, disinhibition, talkativeness, the appearance of relaxation and euphoria.
— 0.6 – 1 ‰ — the average degree of intoxication. Dullness of sensations, weakening of self-control, loss of logic in reasoning, memory lapses after sobering up are possible.
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1 – 2 ‰ — the degree of intoxication is above average. Speech becomes almost incomprehensible, reflexes and coordination are severely impaired, mood swings and manifestations of uncontrolled aggression are possible.
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2 – 3 ‰ — a significant degree of intoxication: confusion and loss o
...f consciousness, severe motor impairment.
— 3 – 4 ‰ — a strong degree of intoxication: a violation of the heartbeat and breathing, uncontrolled vomiting and urination, the inability to stand and move straight.
— above 4 ‰ — a critical degree of intoxication, a fatal outcome is likely.
Note that for some breathalyzers, the lower limit of the measurement range is indicated as "0". You can estimate the lowest concentration of alcohol that such a device is guaranteed to be able to detect using the maximum error (see below): the lower limit of the range will approximately correspond to the claimed error.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.
Test time
The time it takes the instrument to test — in other words, the time that elapses between the end of the purge and the display of the final result. This is one of the parameters that determine the performance of the device (along with the warm-up time and purge time, see above). At the same time, we note that it makes sense to specifically look for a device with a short testing time (
10 s or less) mainly for mass flow checks, when “every second counts” — for example, for pre-trip control of drivers at a large auto enterprise. If we are talking about episodic measurements — for example, individual self-control after "celebrations" once or twice a month — you can get by with a device with a
low speed.
Tests counter
Built-in counter that records the number of measurements taken. The features of the operation of such a
counter can be different — in particular, it can count from the beginning of the day, from the moment it was turned on, from the moment the sensor was last calibrated, etc. These details should be clarified separately. Anyway, the meaning of this function lies in the fact that most breathalyzers have restrictions on the number of measurements per day, and without automatic counting, it can be difficult to monitor compliance with these restrictions. In addition, the calibration and maintenance of the sensor also needs to be done after a certain number of measurements.
Upper limit
Possibility of operation of the device with the established upper
limit of the norm. If the measurement results do not exceed this value, the device will simply display them on the display, and if exceeded, it will give a warning signal. The limit of the norm, usually, the user can set at his discretion within the measurement range.
This function is very useful in situations where you do not need to determine the exact content of alcohol in the blood, but only to check whether it is within the allowed level. And some advanced models with this function have advanced features and are able, for example, to control an electronic lock, opening it only if the result does not exceed the normal limit.
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.
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.