To limit the probability that the surfaces of ramps, landings and treads will be slippery, which could lead to difficulties in moving in an emergency situation, which could lead to delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons.
To limit the probability that the surfaces of ramps, landings and treads will be slippery, which could lead to persons tripping, slipping or falling, which could lead to harm to persons.