BS 1147:2010 pdf download – Portable ladders for fire service use

BS 1147:2010 pdf download – Portable ladders for fire service use 7 Extending ladder requirements 7.1 Force The force to fully extend the ladder shall not exceed 500 N for mechanically operated extending ladders and shall not exceed 260 N for push-up extending ladders. 7.2 Lines The minimum line diameter shall be 8 mm for ladders up to 260 N to extend and 14 mm for ladders between 260 N and 500 N to extend. Lines shall not obstruct the climbing of the ladder and, where they lie on the front face, a fitting shall be provided to secure the line. The line shall be attached to the ladder such that the surplus does not foul its operation. 7.3 Cables Cables shall have a:  minimum breaking load of 2 845 N including its attachments;  means of adjustment;  closed eyes when used on cable attachments;  pulley that is only removable by pulling it through the eye. 7.4 Additional safety requirements Ladders shall be designed and constructed so that it cannot be over-extended. When operating the ladder, it shall be designed and constructed in such a manner that if the rope is released in operation, the ladder shall stop or the section(s) shall be lowered in a controlled manner. NOTE Compliance with this section should be without affecting the continued safe operation of the ladder. 7.5 Pawls Pawls shall be fitted two to a section, to hold the ladder at any extension at which the section rungs coincide. Each pawl shall be capable of supporting the required loads (see Annex G) on its own. NOTE 1 Pawls should be visible from the ground and when climbing the ladder. NOTE 2 Pawls should preferably be independent but may be linked if desired. 8 Fittings 8.1 Hooks Hooks, where fitted, shall conform to the following. The tip of any hook shall be not less than 260 mm and not greater than 600 mm from the adjacent side of the ladder. Roof ladder hooks shall be constructed so as to minimize damage to the roof surface when the hook comes into contact with the roof. Where two hooks are fitted side by side the contact points shall be not less than 250 mm apart (see Figure 4). 8.2 Feet The parts of all types of ladders in contact with the ground shall have non-skid fitments. 8.3 wheels The fitting of wheels...