Page 49 - Dubai Universal Design Code
P. 49

7.  The projection of a step nosing over the tread below shall be avoided, and if present,
                   it shall be at a maximum of 25 mm.


               8.  At least 30 mm from the step edge shall present a reflectance contrast of at least 30
                   LRV points against the step surface.

               9.  In a staircase, all the steps shall have the same height with a tolerance of ± 4 mm.

























                           Figure 20. Step nosing is not advisable and is limited up to 25 mm


               5.8.2.      Stair flights

               Each stair flight must meet the following characteristics:


               1.  A warning surface as per section 5.3 shall be provided at the beginning and the end
                   of each stair flight.

               2.  Each flight shall have between 3 steps and maximum of 12.


               3.  The usable width of the flight shall be at least 1200 mm.

               4.  The width of stairs should be free of obstacles overhead, particularly the underside
                   of the stairs themselves. The minimum usable width is measured between walls or
                   guardrails, without deducting the space occupied by the handrails as long as they do
                   not protrude from the walls or guardrails more than 120 mm.


               5.  Illumination at the top and bottom and along of the flight should be, at least 200 lux.










                                                                                                           48
   44   45   46   47   48   49   50   51   52   53   54