ONLINE VERSION K4Section 4: Protection from collisionIntroduction to provisions Spaces used only for maintenance4.1 This Approved Document sets out some 4.4 In spaces which are used infrequently, and ways of complying with the requirement for only for the purpose of maintenance, provisions windows, skylights and ventilators. such as clear marking of the projecting part to make it easy to see will satisfy the requirement.Projecting parts4.2 Parts of windows, skylights and ventilators that project either internally or externally more than about 100mm horizontally into spaces which are used by people moving in or about the building should be:a. not less than 2m above the ground or floor when in any fixed position; orb. marked by a feature such as a barrier or rail about 1100mm high to prevent people walking into the projecting part (see Diagram 16); orc. marked by provision of surfaces with strong tactile differences or by suitable landscaping features, so that people are guided away from them (see Approved Document M and Diagram 17).Diagram 16 Marking by a barrierSee para 4.2Diagram 17 Marking by a surfaceSee para 4.2Approved Document K Protection from collision15ONLINE VERSION