26. Operating conditions: Portable ladders shall:(1) rest on a firm base with the upper part propped on the 2 siderails;
(2) be firmly held in place by one or more persons, if they are not firmly attached and if their length is equal to or more than 9 m;
(3) be protected against any sliding and against any shock that could compromise equilibrium;
(4) if not firmly fixed, be so inclined that the horizontal distance between the base of the ladder and the vertical plane of its top support is approximately between the quarter and the third of the length of the ladder between its supports;
(5) where used as a means of access:(a) be firmly fixed in place;
(b) extend 900 mm beyond the top storey;
(c) have a space behind the rungs of at least 150 mm;
(6) be set in such a manner that there is sufficient space at the base allowing safe access;
(7) never be used as a horizontal prop;
(8) never be linked to another ladder, end to end, by lapped joints;
(9) when used close to electrical conductors, be made of wood or other insulating material;
(10) have a sufficient length so the worker does not work from the 2 top rungs;
(11) not be put on scaffolding, an elevated platform, an aerial basket or platform, on crates, barrels or in front of a door opening onto the ladder.