It depends on how many factors on when you can drive on it. Depends on what type of product was used and if there were any additives to make it dry faster. The weather plays a huge role as well. Humidity and temperature. Also depends if the area was in direct sunlight or if it was shaded.
A full 24 hours and it should be dry. If anything, heavy trucks or trailers might mark up the seal a little bit but it will fade over the course of 1-2 weeks. I would go ahead and say after 24 hours it is good to go. Of course longer the better but when time is critical it would be fine after 24 hours.
Owner and Operator of Johnson Asphalt Maintenance
providing sealcoating to the Portland Metro area. Over 20 years experience in sealcoat and general asphalt maintenance.