Specifications include, but are not limited to: Ramp surfaces are stable, firm, and slip resistant. Exposed exterior ramps and their approaches are constructed to prevent the accumulation of water on walking surfaces. Ramps used as part of means of egress have a maximum slope of 1:12. The maximum rise for any run is 30 inches. Ramp cross slopes are not steeper than 1:48 ; Ramp surfaces are stable, firm and slip resistant. Exposed exterior ramps and their approaches are constructed to prevent the accumulation of water on walking surfaces. Ramps within the accessible route of travel shall have landings at the top and bottom, points of turning, entrance, exits and doors and at least one intermediate landing for each 30 inches of rise with a minimum dimension of 60 inches in the direction of the ramp run