Digital vs. Infrared Thermometres

Gone are the days when mercury thermometres were the one and only choice we had. Over the years, slowly but surely digital thermometres became the most popular as they were more convenient to use and less dangerous in case of a fall. But soon after their appearance on the market, a new model of thermometres appeared, the forehead non-contact thermometers. Although both of these thermometers measure the body temperature accurately, they don’t work the same and have some major differences.

What Is an Infrared Thermometer?

An infrared forehead thermometer is a device that takes in the emitted radiation by the object and calculates its temperature. Also known as a non-contact thermometer or laser thermometer, the infrared forehead thermometer is an accurate, fast and convenient device because it provides results in no time without having to touch it to the forehead. A thermometer of this kind uses the formula of characteristic radiation, so the matter that has a temperature above absolute zero always emits radiation relative to its temperature.

What Is a Digital Thermometer?

A digital thermometer is a device that can measure body temperature through direct contact with the skin. These thermometers give an exact temperature that is shown as a numerical reading on the screen. The results (values) show up in decimal points making reading easy and precise.

Comparing Infrared and Digital Thermometres

Their Use

As we already mentioned, an infrared thermometer can measure temperature from a distance by absorbing the radiation that is emitted from the item’s body. Thanks to the laser, a thermometer of this kind can point its light beam towards the forehead of the person without the need to come into direct contact with them.

Digital thermometers, on the other hand, are contact thermometres that need to be in contact with a person in order to measure the right body temperature. Now, these thermometers can be used in three ways:

• Orally – inserting it inside the mouth;
• Rectal – putting the probe inside the bottom;
• Axillary – placing the thermometer under the arm.

Accuracy

Truth be told, the touchless thermometer is more comfortable to use and is very precise. The most important thing you need to know about these thermometres is that when measuring the temperature, the distance between the device and the person shouldn’t be very large. The laser should point towards the desired spot, otherwise, the thermometer would start taking in the radiation from the surrounding area. Another crucial thing you need to know about measuring the body temperature with a non-contact thermometer is that the obtained temperature is about 0.3 to 0.6 C lower than the oral temperature.

Measuring body temperature with digital thermometres can also differ, especially if measured in all three ways. When comparing all of them, it is said that rectal checking is far more reliable and accurate than the two other ways of measuring with a digital thermometer. The least accurate is the one used under the arm because the device isn’t in touch with the core parts of the body.

Applications

While the most common use of these thermometers (known by people) is to measure body temperature, they can also be used for industrial, agricultural and food safety purposes. When used for industrial purposes, people use it to see whether or not there are any hot spots in a cooling panel, to check for any leakage in the duct, etc. When used for agricultural and food-safety purposes, it’s mainly used for checking if the surrounding temperature is ideal for the growth of fruit and veggies.  So, if you’ve ever doubted about ‘do forehead thermometers work or not, this can give you peace of mind.

Digital thermometers can give you readings in decimal places and besides measuring the body temperatures, they can also be used in fluid mediums. The most basic and ideal example of its use in a fluid medium is the use of digital thermometers in baby baths. That way, parents can ensure the right bathing temperature.

Benefits and Drawbacks

As we all know by now, one of the biggest benefits of infrared thermometres is their ability to measure temperature within seconds. They are quite safe and can be used on babies and children of all ages and as well as on adults. In order to give you accurate results, following the manufacturer’s instructions is essential. The main downside of these thermometres is that their readings can be affected by external factors like air conditioners, wind and direct sunlight.

Regarding digital thermometres, we already said that they are also pretty accurate. The main drawback of these thermometres is the time reading, it’s slower than the one with forehead thermometers. Additionally, cleaning the device on a regular basis is needed since they can be used in the mouth, underarm and in the bottom. If planning to use it in different places, having separate ones might be needed.