The highest permitted standing level on a stepladder is two steps down from the top. A person standing higher may lose their balance and fall. A person’s maximum safe reaching height is approximately 4’ higher than the height of the ladder. So for example, a typical person can safely reach an 8’ celing on a 4’ ladder.
Extension ladders should be 7 to 10 feet longer than the highest support of contact point, which may be the wall or roof line. This will allow enough length for proper support, overlap of ladder sections, height restrictions etc. The highest standing level is different on extension ladders. It is recommended that standing four rungs down from the top of the ladder will give you the correct support.