Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 31·3.33
Visual contrast on stair steps
Step nosings must have permanent visual contrast distinguishable to visually impaired persons, with the contrast strip measuring between 50 mm and 60 mm wide on all treads and risers.
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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