If the children are physically and psychologically safe, they are available for learning. And parents can rest and relax at home or at their jobs, knowing that the children are safe. But after having said that, you're talking about doing everything that's reasonable and prudent to ensure, to the best of your ability, that indeed everyone's safe. There are practices that we're relentless about. Nobody can enter our building without going directly to the office, signing a form and getting a visitor's sticker.
Volunteers wear badges to that effect.
Children know that they cannot set foot out of their classroom without a pass in their hands. I'm rigid about that. Staff members and the children have been taught to notify the office immediately if they see someone without a badge or sticker in our building or on our grounds. The children are alert, and share quickly. Our building services staff, as part of their role, police the grounds.