Design

The design, construction and installation of the anchorage system for a fixed access ladder shall be capable of withstanding the anticipated loads from the ladder.

The following are the minimum criteria to be used in the design:

  • The minimum design live load should be two loads of 1.1 kN each concentrated between any two consecutive attachments.
  • Other loads, such as concentrated loads, loads due to ice, wind, rigging and impact, and dead loads, must be considered in the design.
  • A safety factor of at least 4:1 should be applied in designing components for normal usage, and at least 10:1 for components supporting fall-arrest systems.

Attachment and Anchorage

The attachment method must be rated for the intended structural service and take into consideration the type of wall or member which will support the ladder.

  • Expansion anchors should be avoided with masonry walls. Since anchor manufacturers' pull-out ratings are usually given for poured concrete walls, they cannot be reliably attained in masonry walls.
  • Through-bolted connections, or equivalent, must be used for masonry walls, and other walls for which there is no anchor manufacturers' pull-out rating. Generally, through-bolted connections should be used wherever practicable.
  • Attachment and anchor bolts should have a minimum diameter of 12 mm.
  • Maximum spacing of attachment points for a steel ladder with side rails shall be 3 m.
  • For different materials or extra loads, this maximum spacing must be adjusted in accordance with recognized design practice.

To provide an improved margin of safety, there should be two means of anchoring the top of the ladder. This may be accomplished by fastening the side rail extension above the top of the access/egress level to the roof.

If a ladder is to be attached to an existing wall, the structural soundness of the wall must be investigated to ensure it is capable of supporting the ladder.