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Are Thermometer Guns Accurate?

Are Thermometer Guns Accurate?

With the recent surge in coronavirus, temperature screening has become commonplace in many businesses, schools, and care homes across the UK, and even the world. They are, after all, one of the many measures used to prevent the spread of coronavirus.

But are thermometer guns accurate? This is a widely debated topic that has a huge impact on the safety of the population.

Are Thermometer Guns Accurate?

When looking at articles about this subject on the internet, many claim that thermometer guns are inaccurate. But they state that they’re inaccurate because of the human error involved with taking temperature.

In other words, the thermometer guns are accurate but people need training to use them.

That doesn’t seem like a good reason to brand them as inaccurate.

In fact, this paper shows that no-contact thermometers are just as accurate as oral or rectal thermometers, when used correctly. This one also supports the use of infrared thermometers.

Because of this, we see no reason for thermometer guns not to be used to protect against COVID-19. While internal thermometers are the gold standard, thermometer guns can provide a quicker, easier result for mass screening.

What Are the Benefits of Using Thermometer Guns?
Better Than the Alternatives

When it comes to considering the best device for protecting your school or care home, there really is nothing better than a thermometer gun.

Ear thermometers produce too much waste, while rectal thermometers consume too much time individually testing employees or visitors. Also most people probably may be uncomfortable with that type of temperature screening.

Thermal imaging cameras are also being pitched as an idea for detecting coronavirus. However the government has stated that these aren’t accurate methods of screening for COVID. They are not medical products and aren’t suitable to be used this way.

There are a number of options and it’s important to choose the best thermometer for your needs.

Measurements Can Be Taken from a Distance

Unlike ear and rectal thermometers, infrared thermometers don’t need to come into contact with a person.

Instead temperature can be safely taken from a distance, making it safer for staff members and visitors.


Following on from the last point, non-contact thermometers are more hygienic.

As there’s no contact involved, there’s no risk of spreading the virus. This means that there’s no need to have multiple thermometers in care homes, for example, as each resident’s temperature can be easily taken without risk.

These thermometers can be easily and immediately used on another without any issue.

No Ongoing Costs

When you’ve purchased your thermometer, that’s the only price you have to pay. There’s no need to purchase thousands of ear probe covers to dispose of after each test (which is also better for the environment).

Plus with a battery life of up to 300 measurements, it’s unlikely that you’ll need to change the battery often.

Fast, Accurate Readings

By using a thermometer gun, a crowd of people can quickly and accurately have their temperatures checked.

Thermometer guns provide a reading in a matter of seconds. Plus, with models like the Marsden T-100, sound is used to notify users of a fever. A healthy temperature is accompanied by one beep, while the thermometer will emit ten short beeps if temperature is high.

What Are the Disadvantages of Using Thermometer Guns?
Human Error

This is one of the biggest issues with using thermometer guns for temperature screening.

Some people may assume that this device is simple to use so no training is required. However there are a few steps that must be carried out to take an accurate temperature reading. Once these have been learnt, then it’s relatively easy to get accurate results every time.

Cheap Versions

The thermometer market has boomed since the start of the pandemic, that can’t be denied. But this has led to a lot of cheap, tacky options, as with any product.

Ebay and Amazon all offer unbelievably priced options. But beware that they may not be as accurate as a thermometer purchased from a trusted brand.

A thermometer that costs £15 vs £30 is unlikely to be as accurate or reliable. Make sure you take this into account when purchasing.

On a similar note, using industrial thermometers, such as those intended for checking the food or temperature of metal, are not going to be as accurate as those intended for medical use.

Obscured Results

It is possible to affect the accuracy of results by obscuring the thermometer. If there is steam or dust in the air, such as at a kitchen or building site, results may not be as precise.

Try to avoid carrying out temperature screening in these environments.

A dirty or scratched thermometer can also have a similar result. Ensure the screen is clean of grime and marks to provide the most accurate results.

How Can You Improve the Accuracy of Thermometer Guns?
Ensure You're Screening Users at the Recommended Distance

If used correctly, these products can be a great step for screening against coronavirus.

One of the issues that is brought up often is that the distance between thermometer and subject is not correct. To remedy this, try adding tape to the floor. Once the subject has stepped on the tape, then you know the distance is correct.

Allow Thermometer Gun to Reach Room Temperature

Sometimes it’s important that thermometers are allowed to come to room temperature before screening begins.

This is very important when they’re stored somewhere that is warmer or colder than the temperature of the location where screening will be carried out.

Choose a Medically-Approved Thermometer

One of the simplest ways to ensure that your thermometer is accurate is to choose a medically-approved thermometer.

These thermometers have undergone further testing to ensure that they’re accurate for use in a medical environment. This means that they’re even suitable for use in hospitals by the NHS. Therefore they’ll provide accurate, reliable results every time.

While they come with a higher price tag, they’re a thermometer that you can count on.

Marsden’s thermometers are medically-approved and used by the NHS.

Further Reading

The older generation are at the highest risk of dying from COVID-19. That’s why temperature screening is important for protecting care home residents.

One of the reasons that thermometer guns are assumed to be inaccurate is because they're not used correctly. Read this guide to find out how to correctly use your thermometer.

Temperature screening has become increasingly popular for businesses. But what are the benefits of temperature screening?