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Q & A: The three second rule

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Most recent answer: 10/22/2007
Q:
does the "3 second rule" actualy work? will bacteria on the floor get on it more if it is left there longer or does it not mater would it mater at 5 or more sceonds (everyone has their own variaton on the number of seconds) Thanks
- James
U.S
A:
Nope, all of these "rules" are rubbish. It does not take any time to transfer bacteria from one surface to another when they are in contact (in fact, that's what "contact" means -- electromagnetic forces are felt between the two objects.) When two objects are in contact, any fluid on one surface may wet the other, and carry bacteria along.

If these rules were for real, you'd never be able to wipe anything off the floor with a towel. All the bacteria (which do not have little stopwatches) and water and other stuff (which also does not have a stopwatch) would somehow have to wait the allotted time before being able to get wiped up. If you mop up a spill on the floor with your pizza, whatever was on the floor will be on your pizza, no matter how little time it took you to do it.

Tom

(published on 10/22/2007)

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