covid-19 screening, the temperature reading could be off by two degrees Celsius or more, if the cameras are of low quality.The cheapest are temperature guns being handed to security guards to point at visitors.
Then there are thermal cameras being placed alongside the usual security cameras at entrances. These cameras, mostly sourced from China, are of dubious virtue apart from their low cost.IPVM, an independent site monitoring video surveillance, recently reported that many thermal camera manufacturers had made false claims about accuracy.
Some were palming off heat-sensing devices meant for detecting fire or the presence of humans as thermal scanners for covid.