Breakfast and lunchPer the rumour, McD was testing it in the kitchen area during the breakfast and lunch periods. The only way they'd know if it detected virus is if someone working there has it and could be tested afterward or tested positive beforehand. McD surely wouldn't put someone they knew had the virus in the kitchen just to test a new machine. So maybe they were trying to get a handle on false positives -- would the things floating around in the air, the aromas and ingredients and heat, set off the alarm. I'm betting they didn't set off the alarm and this part of the process concluded satisfactorily..