Can an electronic thermometer replace mercury?

Since childhood, we are all used to measuring body temperature with ordinary glass mercury thermometers. Their cost is low, they give fairly accurate readings, and besides these thermometers have an unlimited lifespan, unless accidentally broken up during shaking. Most likely, it was this reason that caused some to switch their attention to electronic thermometers, because one of their significant advantages is the safety in use.

Such a thermometer is not terrible to drop, because it does not contain mercury, and if it suddenly breaks, then it will not do any harm. For people who have poor eyesight, this thing can also become a real find, because the electronic thermometer has a liquid crystal display that clearly shows the temperature, and now it is not necessary to look at the indicators of the mercury column. Such miracle-meters are sold in any pharmacy.

However, such a thermometer also has some peculiarities. The instruction says that after the signal is sounded, you do not need to immediately look at the results, but it's better to hold another two to three minutes. During this time, the readings may increase by half a degree or degrees. This feature is explained by the fact that the electronic thermometer has too small a sensor that does not contact the body sufficiently. That is why the testimonies that are obtained are somewhat understated. In general, it is best to not pay attention to the sound signal at all and keep the thermometer for three minutes (regardless of the manufacturer). Moreover, in most countries where these grades are released, the temperature of the body is measured orally or rectally, and not under the arm, and most likely the meter was created taking this into account.

I would like to note that the highest accuracy of measurement has certified instruments, therefore it is worth to be cautious towards Chinese counterparts, not all of them have good quality. The principle of operation of the thermometer is based on changes in the electrical resistance of the conductor, and then converting it into numerical values, which are then output to the liquid crystal display. When determining the temperature, the device tracks its change, and when the temperature of the sensor stops changing and stabilizes, the electronic thermometer will signal that the measurement is completed.

Separately it is necessary to mention the thermometers for children. The device of some of them allows to measure the temperature of the child's body even when he is sleeping. It is enough to carry the appliance over the forehead of the child, from the temple to the temple. Other degrees in form resemble a standard electronic thermometer, but have a bright, "toy" design. This thermometer electronic child safe for the baby, because it has a flexible tip and does not contain glass and mercury. In addition, many thermometers have a waterproof housing and memory that stores the results of the previous measurement. There are also ear meters. Most of the children's thermometers measure the temperature quickly enough, literally within 10-15 seconds. This is very convenient, given the restless nature of the kids.

Whichever electronic thermometer you choose, remember that in order to obtain reliable results, you must strictly follow the instructions that are attached to the device. If this is not done, there may be an increase in the error in the indications, both in the direction of increasing and decreasing temperature. If you rely on the feedback of people using electronic thermometers, you can come to the conclusion that the instruments of different firms work differently and the error is also different, depending on how you measure the temperature. Often to check the correctness of the result, use an old kind mercury thermometer.