I had a cold two weeks ago. A couple times when I sneezed and wasn't quick enough to cover my face (hands were carrying stuff), part of me landed on the wall across the room. More than two meters. To me, close contact would be two to three meters.
"TRANSMITTAL MECHANISM
To graphically illustrate the transmittal mechanism, a video recording was made of a subject talking under back lighting conditions. Large amounts of spittle was projected from the subject during the formation of words beginning with f, p or t. (See Figure 14). The projection distance was two to three feet under normal talking conditions. Coughing Figure 11 Medium magnification SEM of spittle area with generated gross amounts of saliva and dead lung tissue which KCI crystals. could project four to six feet from the subject. Sneezing of course, was the worst case, projecting saliva ten to fifteen feet at speeds as high as 200 mph. The tuberculosis Society made a movie some twenty years ago that vividly demonstrated the way in which TB was transmitted. In many oriental countries, it is common place to see face masks worn to prevent airborne flu and cold virus from being inhaled after someone sneezes in close quarters. What is new, is that fabrication and assembly facilities seem to be unaware of the fact that talking generates a large amount of projected saliva. This is not entirely unexpected since the saliva projection is not visible to the talkers under normal lighting conditions. "
Here the concern is that a single tiny drop of saliva will land on an IC surface.