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The Curious Bag
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<h4 class="dechead">On One Hand: There is a Simple Formula
To ensure maximum safety when using an extension ladder, the base of the ladder must be placed at a distance that measures one-fourth of the height to the ladder's upper support point. For instance, if an extension ladder must reach to a point 20 feet high, the base of the ladder must be placed 5 feet from the base of the wall or other vertical surface. In addition, if the upper support point is the edge of a roof or other elevated surface, the top of the extension ladder must extend 3 feet past the support point.
On the Other: An Extension Ladder Isn't Always the Best
If a work area is too far down the wall, an extension ladder can be too long. The American Ladder Institute cites a scenario using a 28-foot extension ladder, retracted to its minimum 14 feet. Any point on the vertical surface below 10 feet will be too far away to be reached safely. In such instances, it is advised to use another type of ladder, such as a step ladder.
Bottom Line
As with any tool, proper use is required for safe operation. Proper use includes using a ladder long enough to support you safely.
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