Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 31·3.33
Step nosing visual contrast
Steps must have step nosings with permanent visual contrast of 50-60 mm width to help visually impaired persons identify treads.
So a visually impaired person can appreciate the extent of the stair and identify individual treads, steps should have step nosings which are distinguishable through suitable permanent visual contrast. The width of this permanent visual contrast should be not less than 50 mm and not more than 60 mm to all treads and risers.
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