Ladders straight/extension

For straight or extension ladders following these rules ... 

Types There are many types of ladders. They are classified by material of construction (wood, metal), load capacity, function and design. Some ladders are classified as type I, II, or in, depending on the standard loads (200,225, and 250 lb) used for certain tests. Most ladders are manufactured and sold for use. However, some ladders are job-made ladders, assembled at job sites. Ladders can be portable or fixed in place. Common types of portable ladders are step, platform, straight and extension ladders. Multipurpose ladders adjust to serve as several single-purpose ladders. Some ladders, such as those on truck trailers, have custom designs to fit around other design elements. There are many standards for ladder construction. 

When a straight or extension ladder provides a route to a higher work surface, the top of the ladder should extend 3 ft or more above the upper surface. This provides a handhold when getting on or off the ladder and allows a user to step from the ladder to the upper surface. 

Special Scaffolds There are many kinds of specialty scaffolds. Ladder jacks attach to straight or extension ladders. Two ladders with ladder jacks will support planks between them. Users nail roofing brackets to roofs with steep slopes or suspend them with ropes and proper anchors. The brackets support planks between them that workers stand on. After roofing is complete, users remove the planks and brackets. 

The feet of a straight or extension ladder must be set back a safe distance firom the vertical-ene-fourth the working length of the ladder. Ladders used to access a walking surface or roof must extend at least 36 in. (91 cm) above the landing. 

Are safety feet installed on straight and extension ladders ... 

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