4860 Separate secondary platform access walkway and stair systems (24) 4861 Platform & access way systems (1) Secondary accessways and platforms that may be attached to the building but generally do not form part of the fabric of the building. They are permanent but are not primary accessways or functions. Uses may include maintenance accessways and services platforms. 4866 Roof Hatches and Covers (9) Secondary roof access, usually horizontal or sloping, opening or simply removable. They are permanent but usually are not primary accessways or functions. May include steps or ladders. Roof hatches and covers that are separate elements from the building fabric and when not associated with and/or included in other work sections. 4868 Miscellaneous separate secondary access and platform systems (0) Miscellaneous secondary access systems that may be attached to the building but usually do not form part of the fabric of the building. They are permanent but are not for primary access or functions.