Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 45·8.1
Protection from collision with open windows, skylights or ventilators - General requirements
Windows, skylights, and ventilators that project more than 100 mm horizontally into spaces less than 2000 mm above ground or floor must be fitted with a device to limit projection to 100 mm, or marked with a distinguishable barrier at least 1100 mm high, a high relief surface, or landscape feature.
Where any part of a window, skylight or ventilator, when open, could project more than 100 mm horizontally into a space less than 2000 mm above the ground or floor it should be –
(a) fitted with a suitable device to restrict the projection in normal use to not more than 100 mm; or
(b) marked by a suitable feature such as –
(i) a distinguishable barrier or rail not less than 1100 mm high;
(ii) a high relief surface; or
(iii) a landscape feature,
which extends to at least the maximum projection of the window, skylight or ventilator.
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