The influence of the ETAG 27 Guideline for European Technical Approval of Falling Rock Protection Kits, published in 2008, has been relatively far reaching, including here in North America. ETAG 27 makes it possible to compare products, from different material suppliers, through standardized reporting of testing and material data. However, it does not consider best practices for the implementation or the evaluation of safety and maintenance requirements. A new document published by Austrian Standards Institute - the Austrian national standards body, similar to ASTM and CSA - goes beyond ETAG 27, though in a much more broad spectrum including stabilization with anchoring and meshets, embankments, and galleries. The document is entitled "ONR 24810, Technical protection against rockfall - Terms and definitions, effects of actions, design, monitoring and maintenance", published in January of 2013. Herein, the authors focus on summarizing the parts of the ONR specific to catchment fences beginning with the initial site investigation, which results in the input parameters for the numerical rockfall analysis. The semi-probabilistic verification of the design is then explained by the comparison of the impact parameters, such as energy and bounce height, with the resistance parameters of the catchment fence. Furthermore, helpful design and constructive rules regarding anchor design and fence layout are given. Lastly, maintenance and inspection schedules are presented.
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