As the body temperature is a vital sign in medical sciences, measuring it, is very necessary in health care. The most significant thing in this situation, is that the body temperature must be evaluated in the most accurate way, since it is directly related to the diagnosis of disease or health. Inaccurate measurement can lead to incorrect diagnosis, wrong treatment or inappropriate intervention. There are several methods for measuring temperature and comparing these methods gives space for choosing the best method in terms of accuracy, speed and safety.
Non-contact infrared thermometer is a kind of thermometer which has been designed to measure the forehead temperature of the human body. They have another names as well, such as:
- Laser Thermometers (because they have a laser which helps the device to aim the object more efficient)
- Non-contact Thermometers
- Temperature Guns (to characterize the device’s ability to measure temperature from distance).
The design of these devices are consisted of a lens which helps the infrared thermal radiation to focus on to a detector, that transforms the radiant power to an electrical signal that can be displayed in units of temperature after being compensated for ambient temperature. This performance allow temperature measurement from a distance without any contact with the object to be measured.
Infrared thermometers are not only used to measure human body temperature, but also they can be used to serve a wide variety of temperature monitoring functions including:
- detecting the clouds for remote telescope operation
- checking for hot spots in electrical or mechanical equipment
- checking the temperature of heater or oven
- for calibrating
- helping fire fighters to measure the temperature of hot spots
- monitoring materials in processes which involve heating or cooling,
- At times of epidemics of diseases which cause fever, such as SARS, COVID19 and Ebola virus disease, infrared thermometers are being used to check arriving travelers for fever.
Those kinds of infrared thermometers which are used in medical situations are called Medical infrared thermometers and those kinds which are used in non-medical situations are called Industrial/Environmental thermometers. There is a critical difference between these two kinds. The Industrial/Environmental thermometers measure temperatures over an extensive temperature range to suit a plenty of industrial applications. Temperature measured in these kinds of thermometers can range from -60 °C to over 500 °C. This extent of range means that there is a low accuracy in measurement. The error factor in this kind of thermometers averages around ±1 to 1.5 °C.
In contrast, the output of medical thermometers must be far more accurate, and the range of temperature needs to be around the expected bodily temperatures of a human (32 °C to 42.5 °C) with a level of accuracy of ±0.1 °C. Whenever the difference between well and unwell is only a couple of degrees, and industrial thermometer in not a suitable tool.
Benefits of non-contact infrared thermometers:
- Accurate temperature measurement in 1 second
- No laser spot
- Avoid potential damage to eyes
- No need to contact human skin
- Avoid cross-infection
- One-click temperature measurement
- Easy to use
- Easy to disinfect and clean
- Providing ability to retake a temperature quickly
- Suitable for home users, hotels, libraries, large enterprises, and institutions. Can also be used in hospitals, airports, customs, schools and other comprehensive places.
Appropriate use of non-contact infrared thermometers:
1. Preparing the Environment
The environment can impact the performance of infrared thermometer. To prevent this impact, you should use it in a draft-free space and out of direct sun or near radiant heat sources. Typically, the environmental temperature should be between 16-40 °C and relative humidity below 85 percent. It is good to put the infrared thermometer in the testing environment for 10-30 minutes before use, to allow it to adjust to the environment.
- Preparing the person being evaluated
It is necessary to make sure that the test area of the forehead is clean, dry and not blocked during measurement, and temperature of the forehead test area has not increased or decreased by wearing excessive clothing or head covers or by facial cleansing products.
- Using the non-contact infrared thermometer
The person who is using the device should strictly follow the manufacturer’s guidelines and instructions for use for the specific non-contact infrared thermometer which is using. The typical instructions for using this device is as below:
- Holding the sensing area perpendicular to the forehead and notice the person to remain fixed during measurement.
- Keeping the sensing area in the proper distance which is specific to each non-contact infrared thermometer. Use the manufacturer’s instructions for correct measurement distance.
- Do not touch the sensing area and keep it clean and dry.