Ladders placed in high traffic areas such as passage-ways, doorways, or driveways must be secured to prevent accidental contact which could knock the ladder over. It is very easy for a person to turn a corner or open a door and accidentally knock you off of your ladder by bumping in to it.
A ladder should never be placed in front of a door unless:
The doors have been locked to prevent use,
The doors have been blocked with barrier tape or a sign that warns that there is a person on the ladder or
A person is standing on the other side of the door to prevent anyone from entering when the ladder is being used.
When using a ladder in an area where many people can potentially bump in to it, place warning signs or barricades to guide people away from the foot of the ladder. If this is not possible, have someone hold and guard the bottom of the ladder.