Light foot traffic is usually fine after 12 to 24 hours. Hand carts and light equipment follow at 24 to 48. Vehicles and forklifts wait 48 to 72 hours, and full chemical resistance keeps building for several days after that.
For a facility the useful question is not when the floor is walkable, it is when you can run again. Those are different dates. You can often get staff back on foot the next morning while the lift truck aisle is still closed, which means a phased reopening rather than one long shutdown.
Plan it by zone. Open the areas people walk through first, hold the equipment lanes, and let the last coat finish curing while the rest of the building works around it.
Planning a shutdown around a floor? Here is how we run a phased commercial epoxy install in St. Louis.