Choosing the right size or length ladder is just as important as the style. One of the most common and potentially dangerous ladder selection mistakes is purchasing a ladder which is either too short or too long.

Which kind of ladder is right for the job - step stool, stepladder, extension ladder or multi-purpose ladder? The intended task and the work environment help determine the style of ladder best designed to keep you safe and productive on the job.

Extension ladders should be 7 to 10 feet longer than the highest support or contact point, which may be the wall or roof line. This will allow the user the sufficient length to set up the ladder properly. Overlap of ladder sections, height restrictions of the highest standing level, and where appropriate, the extension of the ladder above the roof line. The highest standing level should be four rungs down from the ladder top. Never stand on the ladder higher than the support points or roof line. 

The highest permitted standing level on a step ladder is two steps down from the top of the ladder. Users standing higher may lose their balance and fall. A user's maximum safe reaching height is approximately 4' higher than height of the ladder. For example, a typical user can safely reach an 8' ceiling on a 4' step ladder.