Let's first understand the temperature measuring principle of electronic thermometer.
Technical principle of infrared forehead temperature gun;
Any object will release infrared radiation energy, and its surface temperature determines the size and wavelength of radiation energy, which is based on this principle. The forehead temperature gun is equipped with a high-precision infrared sensor, which measures the infrared radiation energy with the wavelength of 5- 14μ m released by the human body, and measures the human body temperature through accurate calculation and compensation correction.
Infrared thermometer (forehead temperature gun, ear temperature gun, etc. ): By measuring the radiation temperature of the forehead or eardrum, the human body temperature can be measured.
Compared with the traditional mercury glass thermometer, the electronic thermometer has the advantages of convenient reading, short measuring time, relative hygiene, memory and voice prompt, no mercury electronic thermometer and high safety, and is suitable for families and hospital patients with babies.
This year's epidemic has made more people use electronic thermometers. In the process of our use, we often find that the numbers measured by electronic thermometers are different every time, and some are even worse. It has aroused people's doubts and distrust of electronic thermometers.
Actually, there are several reasons for this.
1 First of all, it should be clear that the forehead temperature gun has errors in most scenes. The forehead temperature measuring gun is different from the actual temperature in the accuracy and stability of temperature measurement. This mainly depends on the accuracy of the sensor used by the manufacturer. The quality of domestic brands is uneven, and the deviation of foreign brands is slightly smaller.
Comparison of performance indexes of temperature sensor of electronic thermometer
2, forehead temperature gun, the error is affected by the environment and temperature, it has a working temperature range.
Maximum permissible error: The domestic error is 0.3℃. Measuring range: 35-42 degrees
Working environment: temperature 16-35℃ and humidity ≤85%.
Too hot or too cold. Therefore, we often see in the epidemic news that the forehead temperature gun doesn't work at low temperature, and it needs to be put in your pocket for preheating before it can work normally.
3. The forehead temperature gun is affected by different temperatures and environments, which will affect the measurement results. So our temperature measurement method is also very important.
Temperature measurement method: the forehead temperature measuring gun is aimed at the center of the forehead, above the eyebrows, and kept vertical. There should be no hair covering or sweat on the measuring parts. The infrared head should be 1-3 cm away from the forehead skin, not too far away and not touching the skin. Hold it steady, don't shake your hand, and point it vertically to your forehead. It is best to keep the temperature measurement for a short time. After 2 seconds, the temperature number is displayed on the display screen, and then the forehead temperature gun is removed from the forehead.
Note: The measured object should be kept in a stable environment for at least 5 minutes. Do not do strenuous exercise, sunbathe, go in and out of air-conditioned rooms, blow fans, take a shower, etc. In 30 minutes You can have a rest before taking your temperature. If there is a baby at home, pay attention to the temperature change after feeding and crying, in an air-conditioned room and under the bed. It is recommended to measure three times and choose the one with the highest temperature.
If the temperature measurement error is too big and there is a baby at home, you can use an electronic thermometer as a temperature screening. If the electronic thermometer first detects an abnormal temperature, use the mercury thermometer for confirmation. During the epidemic, some of our prevention and control points did just that. If the electronic thermometer detects an abnormal temperature, it must be reconfirmed with a mercury thermometer.
Of course, some temperature cannons are still very accurate. At home, especially for children and babies, a mercury thermometer will be prepared when preparing the forehead temperature gun, and the temperature errors of the two thermometers will be compared at any time to maintain the accuracy of the forehead temperature gun. If the error is too big, change the forehead temperature gun and don't miss the baby's health.
The difference between forehead temperature gun and ear temperature gun
Both forehead temperature gun and ear temperature gun use the principle of infrared temperature measurement. Because our foreheads are exposed, we are easily affected by the ambient temperature, which leads to many inaccurate results. The ear thermometer measures the temperature of the eardrum, which is located in the deepest part of the external auditory canal and is not easily affected by the external environment. The results can reflect our body temperature more accurately. So the accuracy of the ear thermometer will be higher.
However, it should be noted that direct contact with the ear thermometer poses a risk of infection. In addition, the temperature measurement method is not easy to master, and the ear thermometer should go deep into the ear canal, which may be difficult for children to cooperate with.
Special reminder-electronic thermometers have a service life, usually five years. Electronic thermometers belong to medical devices and should have the approval number of medical devices. Pay attention to identification when buying. Your situation is that the electronic thermometer has not dropped to zero. Let me talk about the reasons for this situation first. Your thermometer is broken and inaccurate. Need to check or replace a new thermometer, that's the case.