Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 16·2.4
Visually impaired people and changes in level
Warning of level changes must be positioned in advance of the hazard to allow time to stop and should not be so narrow that it might be missed in a single stride, particularly at the head of steps where descent is most hazardous.
Visually impaired people risk tripping or losing their balance if there is no warning that there is a change in level. Tripping is most hazardous at the head of a flight of steps when a person is descending. The warning should be placed sufficiently in advance of the hazard to allow time to stop and not be so narrow that it might be missed in a single stride.
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