Why Choose Engineered Anchor Points?

Suggestions are always given on how to select a non-engineered anchorage. “Hook overhead to something that will hold a truck” (or something similar) is the phrase most often associated with anchorage selection. Although this sentence provides a worker an impression of how to select an anchorage, it certainly falls short of ideal. With each anchor, it’s strength, location, and compatibility with the connector are main considerations. Regulatory agencies have issued minimum strength requirements (usually 5000 lbs.) for the acceptable strength of anchorages, but there is more to an anchorage than strength and that is one of the main reasons an “engineered anchorage” is preferred. Engineering of the anchorage is usually required to determine it’s strength, but Gravitec would tell you that there is much more to an engineered anchorage than just determining its strength. It’s location often determines if the system is used for travel restraint or fall arrest. If it is fall arrest, the anchorage location plays a critical role in determining the free fall distance of the system. There are many “unsafe” 5000-pound anchorages located at people’s feet. Many people would argue (successfully) that a 3600-pound anchorage overhead is better than a 5000-pound anchorage at foot level.

Once strength and location have been addressed, the other main advantage to an engineered anchorage is compatibility with the connecting components. The engineer on record should identify all of the equipment and systems that are acceptable for use on the anchorage (see ANSI Z359.6). A properly engineered anchorage considers all of the equipment that the anchorage is going to interact with. The engineering of that anchorage would consider all of the potential and actual connectors that are going into the connection and take steps to ensure that there is compatibility. If the anchorage is general use and an evaluation of every single connector isn’t possible, there are simple steps that a good designer can take to ensure compatibility. Designing connections to be overhead with flexible features have proven to be effective safeguards when poor connections are made.

Supporting information that comes with (or on-file with) an engineered anchorage is another reason to invest in engineered anchorages. As-built drawings that show fastening methods, calculations and stamps are invaluable as time moves on.