How to choose a medical thermometer. Mercury, electronic and infra-red

The human body temperature is an accurate indicator of the state of his health. How to choose a thermometer to measure it: mercury, electronic and infrared?

2015-12-06 06:54:41 57

thermometerbody temperaturemercury thermometerelectronic thermometerdevices fordevices for measuring

Mercury thermometer

The most common medical devices for measuring body temperature is the traditional mercury thermometer. It is a glass flask, which is placed inside the capillary, filled with mercury. The volume of mercury varies with its temperature – this is the property of and is based the working principle of a mercury thermometer. It is also called the maximum due to the fact that the column of mercury is fixed in a position corresponding to the maximum temperature measurement independently, without shaking, does not fall down. Advantages of mercury thermometers should be allocated to their flexibility, due to which body temperature can be measured in the axilla, oral or rectal way. This thermometer simple to use, has a measurement error of only 0.1 degrees and has the lowest cost from all varieties of devices for measuring body temperature. There are also drawbacks. The chief of the fragility and risk of fracture of the flask, followed by depressurization of the mercury capillary. To gather the scattered droplets of mercury is long and difficult, and carry out decontamination of the premises is expensive. Another disadvantage of the mercury thermometer is the long (about 10 minutes) measurement time.


The main element of the electronic thermometer is a thermistor having the property to change the value of its resistance depending on its temperature fluctuations. Besides there is an electronic module, protected by a casing of waterproof material. The measurement result is displayed on the digital display, located in the housing of the thermometer. Electronic thermometer can measure body temperature both in the axilla and mouth, in the groin and in the rectum. The maximum time required for obtaining the measuring results is 3 minutes. Hygienic requirements to the thermometer implemented a set of replacement caps. There are flaws, but they are few. When measuring the temperature in the armpit you should hold the thermometer after a sound signal about the end of the measurement in another few minutes, in addition, such information may be inaccurate. Not all models of electronic thermometers allow their washing and disinfection.


The principle of this completely new device is to remove a highly sensitive infra-red radiation from the measurement object, and converts it into temperature readings displayed on the LCD screen. As the electronic thermometer, it has a built-in memory, equipped with sound signals and has the function of automatic shutdown. The duration of the process of measuring temperature is from 5 to 30 seconds. The device is irreplaceable in case if you want to measure the body temperature of newborns, capricious or sleeping children, people who are in an unconscious state. Cons of infrared thermometer: the need for accurate positioning of the device, otherwise the measurement error can reach 0.5 degrees, the inability to measure basal body temperature, the need for periodic checks and the high cost of the device. Take care of your health! Be always healthy!

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