Suggest you check out the “BO, things you never thought you had to tell your boarders” thread on Off Course. Lots of food for thought there.
Being in New England where there can be a lot of ice in the winter, I was once at a barn that mandated some type of cleat on our footwear when it was icy. BO did not want to be sued because someone broke their ankle when they slipped on the ice. It was a good rule and probably saved at least one of us a trip to the emergency room.