If you use a ladder instead of scaffolding, OSHA guidelines may or may not apply in regards to the need for fall protection. For instance, when using fixed ladders, you'll need fall protection whenever the climb is equal to or exceeds 24 feet. OSHA classifies a fixed ladder as one that's an integral part of the building or structure. While OSHA does not specify maximum lengths for portable ladders, it does list specific performance requirements that all ladders must meet. OSHA further categorizes these as portable wood and metal ladders with several subcategories under each type.