Are Temperature guns accurate? Here's how the Coronavirus-era thermometer substitutes work

number of cases of vel Coronavirus are increasing around world at an alarming rate and nations are taking steps to tackle dely virus. Ever since outbreak of COVID-19, as a precautionary measure, re has been a need to routinely check body temperature. People are checked at airports, offices, stores and even in residential areas by guards/officials wearing masks with help of infrared rmometer which is commonly kwn as 'temperature gun or 'infra gun'. 

This rmometer is used inste of a mercury rmometer as it gives out results faster and also because it can measure surface temperature without touching people’s skin. So how does this device function and how accurately can it measure human body temperature?

How do infrared rmometers work?

device is equipped with an infrared sensor that can quickly measure surface temperature without making any contact with a person’s skin. Infrared rmometers work based on a phemen called black body riation. According to website 'Sciencing.com', following is method which shows how infrared rmometers work:

"Infrared light works like visible light--it can be focused, reflected or absorbed. Infrared rmometers usually use a lens to focus infrared light from one object onto a detector called a rmopile. rmopile absorbs infrared riation and turns it into heat. more infrared energy, hotter rmopile gets. This heat is turned into electricity. electricity is sent to a detector, which uses it to determine temperature of whatever rmometer is pointed at. more electricity, hotter object is."

How accurately do temperature guns predict results?

Experts say rmometer guns aren’t as accurate as mercury or digital rmometers, but y can be useful in some situations. accuracy of results also depends on how se devices are used, for example, how far it is kept from body it is measuring, how steily it is held and for how much time. temperature can get affected by various factors such as wind and water.

rmometer guns and rmal screening cameras, which measure heat coming off a person, will t catch everyone infected with COVID-19, because re are some who are infected but show symptoms, according to experts. 

Research published in  New England Journal of Medicine in February showed two of 126 people evacuated to Frankfurt in Germany on a flight from China’s Hubei province h tested positive for coronavirus after arrival despite passing symptoms-based screening before boarding plane.

RE | Kerala CM warns those targeting Nizamuddin attendees amid Markaz-linked Coronavirus spre

It can take from 2 to 10 days for a person to show symptoms of coronavirus and WHO has recommended a quarantine period of 14 days. If a person is affected by virus and has t started to show symptoms yet, infrared rmometer would t be able to detect. So, infrared rmometers might t provide an accurate estimation of infected people.

RE | Congress' Abhishek Manu Singhvi backs Yuvraj & Harbhajan's donation to Afridi's charity

According to a prominent US publication, rmometer guns used in screenings are "torious, t active and reliable" since many screeners hold m at wong distance or use m in wrong environment. A report from CNA indicates that even if se devices are t that accurate in measuring body temperature, y can be used as a complementary tool for initial screening, followed by or necessary procedures.

RE | 'Lose identities': Cong's Ramesh laments & opposes Syndicate Bank & Andhra Bank mergers

Despite flaws,  n-contact rmometers or temperature guns have become scarce in market and are being sold at a very high cost which is why people are finding it difficult to procure m.

RE | 'Watch & learn': Prakash Javekar ds ode to DD's Ramayan re-telecast in Ram Navami wish