The 6-ft rule applies to droplets, which fall to the ground. Aerosols transmit differently. Seems that physical barriers and staying outdoors or having good ventilation are your best defense right now.

Prolonged exposure in enclosed areas can create a build-up of aerosols, which, when breathed in, can go deep into the lungs without triggering the immune system, i.e. you have the virus but are asymptomatic. Here is an informative interview of Kimberly Prather, PhD. At 9:40 min she points to the events that indicate aerosol spread.