How to use the human body infrared thermometer
Human body infrared thermometer classification
The pneumonia epidemic caused by the new coronavirus is severe, and measuring body temperature has become a necessary means to prevent and control the epidemic. Because of its non-contact, high efficiency, and easy-to-use features, the human body infrared thermometer is widely used in various traffic gateways, hospitals, residential quarters, enterprises and institutions with dense crowds.
At present, the commonly used infrared thermometers for human body can be divided into two categories: infrared thermal imaging body temperature rapid screening instrument and infrared thermometer.
The infrared thermal imaging body temperature rapid screening device can monitor large areas in crowded public places, automatically track and alarm high-temperature areas, and cooperate with visible light video to quickly find and track people with high body temperature. When the infrared thermal imaging body temperature rapid screening instrument integrates technologies such as face recognition and mobile phone probes, it can also grasp more information about people with higher body temperatures.
Infrared thermometers can be divided into infrared ear thermometers and infrared forehead thermometers. Infrared thermometers are simple in equipment, easy to use, and affordable. The application can realize sequential and rapid temperature measurement of personnel.
How to use the human body infrared thermometer
The human body infrared thermometer can work normally only at a certain ambient temperature. Usually when the body temperature is measured at an ambient temperature lower than 16°C, the data will have a large deviation, or even cannot be displayed. From the perspective of the measurement principle, it is a normal phenomenon. He suggested that it is better to measure in a place where there is no strong convection, no strong radiation, no high humidity, relatively constant temperature, and conforms to the ambient temperature declared by the thermometer.
Taking the infrared forehead thermometer as an example, the temperature of the body surface of the person being measured needs to reach a state of thermal equilibrium with the measurement environment before the measurement can be started. When measuring body temperature, aim the infrared forehead thermometer at the center of the forehead (above the eyebrows and keep it vertical). The measurement site should not be covered by hair, sweat, hats, etc. The best measurement distance is (1-3) cm. Repeat the measurement twice within 1 minute, each measurement time should be maintained (3-5) seconds, the difference between the two measurement data is within 0.3 ℃, the data can be accepted, otherwise it needs to be checked and measured again.
Precautions for using human body infrared thermometer
The advantages of infrared temperature measurement: First, there is no contact with the measured object, and unnecessary infection will not be caused when measuring body temperature; second, it is fast, usually the measurement time is less than 1 second, and generally does not exceed 2 seconds. Therefore, it is very suitable for application in the prevention and detection of fever diseases.
Usually, when the human body temperature is around 37°C, the accuracy of the infrared thermal imaging body temperature rapid screening instrument can reach ±0.3°C, and the infrared thermometer can reach ±0.2°C.
In terms of measurement accuracy, the infrared ear thermometer has the highest measurement accuracy, followed by the infrared forehead thermometer. However, if the measurement method is not correct, the measurement results will also be inaccurate. For newly purchased human infrared thermometers, or when they are used frequently and have doubts about the measurement results, the human infrared thermometer should be calibrated to determine its correction value, which can eliminate the systematic error of the thermometer as much as possible.
The blackbody radiation source can be used to calibrate the human body infrared thermometer. Its effective emissivity and temperature control stability have higher requirements. The blackbody temperature is usually measured with a contact thermometer such as a platinum resistance thermometer or a liquid-in-glass thermometer, and its temperature is compared with the value measured by an infrared thermometer to obtain a calibration value. The black body for calibrating the infrared ear thermometer also needs to design its opening shape and size specially according to the requirements of the thermometer to be tested.
Special Note: It is not recommended to use infrared thermometers for industrial testing to measure human body temperature.
Infrared thermometers for industrial testing usually have a lower limit of the measurement range of -20°C to -30°C, and an upper limit of 200°C to 1000°C. The measurement range is wide and the accuracy is low. Generally, it is not better than ±1.0 near the human body temperature. ℃. Therefore, it is not appropriate to use an infrared thermometer for industrial testing to measure human body temperature only from the requirements of measurement accuracy.
