In this article, Structural Engineer, Mark Duckett, P.E., S.I. discusses the topic of construction guardrail failures. Through video he introduces a properly designed and constructed guardrail and performs testing on that system to demonstrate the inherent safety of a properly engineered system.
Temporary Construction Guardrails: Fall Protection for Unguarded Edges
The leading cause of deaths on construction sites, by far, is from workers falling from heights. As reported by OSHA, over 36 percent of all construction fatalities in 2013 were those resulting from a fall. OSHA generally requires that fall protection be provided for workers in the construction industry when the fall hazard is 6 feet or more; typically occurring at an unguarded edge.
The most efficient, and hence the most common, fall protection system utilized at unguarded edges on construction sites is a temporary guardrail. These systems are similar in concept to those seen at edges of balconies, mezzanines and elevated decks but are temporary in that they are required only during the construction phase of a project; permanent systems will be in place after the structure is completed.
In all of the construction guardrail cases I have been involved in, the temporary construction guardrail failed and that guardrail failure tragically resulted in serious injury or death for the worker involved. In those cases, the guardrail system intended to guard the workers was not designed properly, and that was the proximate cause of the guardrail failure and subsequent injury or death of the worker.
To ensure worker safety, OSHA requires construction guardrails to be designed to resist reasonable and foreseeable loads; those loads are defined in Section 1926.502 (Fall Protection Systems Criteria and Practices) of the OSHA Regulations. There, guardrail systems are required to safely resist a force of at least 200 pounds in an outward or downward direction applied at any point along the top edge and the mid and intermediate members comprising the guardrail system are required to safely resist a load of at least 150 pounds applied in a similar manner. 192 Subpart M Appendix B of the OSHA regulations offers non-mandatory guidelines to assist in complying with the design requirements.
To help my clients understand the benefits of a properly designed and properly constructed guardrail and its capability to safely guard a worker from a falling hazard, I designed, constructed and tested a temporary guardrail system. The temporary guardrail was designed to meet only the minimum loading requirements specified in the OSHA regulations and I then oversaw the construction of that system. The temporary guardrail I designed, constructed and tested utilized 2x4 wood members to match what is typically used on construction sites for guardrail systems.
The following video depicts the properly designed, properly constructed and tested guardrail. Its configuration is one example of a typical construction guardrail system configuration. Highlights of the test can be seen in the video:
As seen in the video of the test, a properly designed, properly constructed temporary construction guardrail system can safely resist loads many times greater than the minimum specified by the OSHA regulation. A properly designed and properly constructed temporary guardrail system is the first step in making safe the workers who would otherwise be exposed to an unguarded edge on the construction site.
Construction Injury Investigations
The Construction Safety experts at Robson Forensic have worked at every level within the industry, from bricklayer on residential projects to project manager on multi-prime worksites. Our experts have done the work central to your case and can testify regarding the hazards, risks, and responsibilities in the construction industry.
Submit an inquiry or contact the author of this article to discuss your case with an expert.
Mark has over three decades of professional experience in structural engineering; in this time he has designed and inspected all types of structures including residential, commercial, marine, industrial, institutional, religious, retail, hi-rise, and warehouse. Mark’s expertise extends to almost every type of building material, including concrete, steel, wood, masonry and many other types of materials. Mark has additional expertise in wind engineering; specifically, how wind acts upon structures and how structures react to the wind. Mark is a Professional Engineer (P.E.) licensed in multiple states. He is also a Special (Threshold) Inspector and in the State of Florida.