First rule is 'Lash it & Foot It', i.e. secured to prevent movement and placed on firm level and dry base. Remembering to position ladder so that the safest angle of use comes when for every 1 x measure out from the wall is matched by 4 x measures up - 1 out 4 up. Do not use the top three rungs, so ensure the ladder is long enough to safely reach the working or access height. Longer ladders will required two or more people to erect. Do not rest ladder against guttering or narrow / plastic features, use ladder stay to lay off surface and hold away from wall. This also prevents possible 'leaning back' problems with access to working area. All aluminium ladders made to BS 2037 Class 1.