Ask Rigid Lifelines: What’s the difference between an engineered system and a non-engineered system?

September 15, 2016

We receive questions about non-engineered fall protection systems and how they differ from engineered fall protection systems on a regular basis. So, let’s take an in-depth look at their basic differences and the load testing requirements for each.

Engineered Fall Protection Systems:

An engineered fall protection system is one that has been tested and validated by a professional engineer and performance drop testing per ANSI and OSHA requirements. Engineered systems require no further static or dynamic drop testing from end users or distributors. This is true for standard engineered systems, along with custom engineered systems, excluding supports not supplied by your fall protection manufacturer.

However, if those anchorage points have been certified by a professional engineer or qualified person—as defined by OSHA—no load testing is required. If the anchorage points have not been certified by a professional engineer, manufacturers require a qualified person, as defined by OSHA, to determine that those anchorage points are five times the strength of the calculated hanger loads.

When installed according to the above standards and maintained according to your manufacturer’s installation and maintenance guidelines, the safety of the fall protection products and their ability to handle the chosen rated capacities and performance standards are a safe bet.

In other words, engineered fall protection systems DO NOT need to be load tested in the field. However, they do need to follow daily and annual inspection guidelines as defined by OSHA and ANSI. This includes fall arrest components, such as standard length runway trusses, hangers, bridges, and trolleys.

We have seen many end-users testing their SRL’s when it isn’t necessary for properly engineered systems. In fact, it costs a lot of money and wasted time to test your own SRL in the field. If you test your SRL’s, their fall indicators will automatically deploy, meaning you need to replace each one before they can be used by workers again.

As per the above specifications, Rigid Lifelines (and most other manufacturers) define the maximum weight per worker, including tools, at 400 pounds and the maximum arresting force of any employed lanyard at 900 pounds MAF (maximum arresting force).

Non-Engineered Fall Protection Systems:

Unlike engineered fall protection systems, non-engineered systems have not been designed, checked, or tested by a professional engineer or competent person as defined by OSHA and ANSI. For this reason, non-engineered systems require much higher expectations, and loading is specific to each system. In other words, per OSHA law 1926.502(d) (15) and 1910.66 App C (I)(c) (10) “Anchorages to which personal fall arrest equipment is attached shall be capable of supporting at least 5,000 pounds (22.2 kN) per employee attached, or shall be designed, installed, and used as part of a complete personal fall arrest system which maintains a safety factor of at least two, under the supervision of a qualified person”. In other words, if it’s not an engineered anchorage point, the support structure must be able to withstand a 5,000-pound load.

Your fall protection manufacturer should be engineering and designing their systems by a professional engineer or qualified person, who ensures the system maintains a safety factor of at least two, per OSHA law. Multi-person loadings should also be based on strict empirical data. When installed according to the above standards and maintained according to your manufacturer’s installation and maintenance manual, you can be assured of the safety of their products and their ability to handle the chosen rated capacities and performance standards.

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