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Filling a previous gap, we’ve now published a new standard on permanent counterweighted guardrails not fixed to the structure. This blog post explains what the standard does and doesn’t cover and what is included.

Until now, there’s been no specific standard for counterweighted edge protection systems that are installed and remain in place for the life of a facility. Instead, we’ve had a European code, Temporary edge protection systems - Product specification - Test methods, covering temporary guardrails, and a British Standard, Barriers in and about buildings. Code of practice, dealing with permanent guardrails installed into the structure. So there was a gap for a specification on permanent guardrails which are not fixed to a structure. Due to industry demand, that has now been filled by Permanent counterweighted guardrail systems — Specification.

Providing clarity

Industry has used permanent, counterweighted edge protection for the last forty years to protect workers carrying out maintenance and repairs to equipment housed on flat roofs. Until now, manufacturers have established their own standards for this category of product by using a combination of Work at Height Regulations, Building Regulations, HSE/SIR 15, BS EN 13374, and BS 6180, as well as for calculating wind loads.

However, it was felt that a dedicated standard would be well received as it would provide the industry with clarity and ensure this category of product is designed, tested, manufactured, assembled/installed, and re-certified in a way that’s safe and fit for the purpose of protecting workers and satisfying appropriate environmental (wind) conditions in the given vicinity. Hence a panel of experts was convened under the auspices of BSI’s Access and Support Equipment Technical Committee (B/514) that included edge protection specialists, suppliers, installers, and health and safety experts.

Mass and friction

BS 13700:2021 specifies requirements for the design, performance, testing, inspection, and marking of manufactured free‐standing permanent guardrails that rely on mass and friction and that are intended to protect workers from a fall hazard. These guardrails are not fixed to a structure.

The standard also provides requirements for instructions; static test methods, including partial safety factors, wind loading, and procedures; the content of test reports and information to be provided as part of the edge protection system; and requirements for inspection and maintenance.

It should be noted that the standard does not apply to temporary guardrails, warning chains, demarcation posts, netting, infill panels, guardrails that penetrate the structure and secure to the substrate, guardrails that support material-handling equipment, or guardrails intended for use on surfaces sloping more than 5?.

Nine sections

The standard comprises nine main clauses. For clarity, the Terms and Definitions include a definition of a counterweighted guardrail system and an illustration of its components. The standard then specifies general requirements for materials, including those used for counterweight and fasteners. Requirements for drainage, finish, and welded assembly are also provided.

Clause 5 covers design requirements for guardrails and encompasses general design, configuration, and counterweight requirements. Partial safety factors are provided for ultimate limit state with fundamental loads, ultimate limit state with accidental loads, and serviceability limit state.

Test requirements for static tests, including loadings and maximum displacements, are provided in clause 7 along with a series of explanatory figures. Particular consideration is given to the exposure area and the effect of wind conditions. The next clause specifies requirements for test samples, equipment, and procedures in considerable detail, including in wet and dry conditions. Requirements for pre-test procedures and the content of test reports are also covered. The penultimate clause deals with markings and the inclusion of information in the operations and maintenance (O&M) manual. The final section covers inspection, maintenance, testing, and examinations, including both pre-use checks and thorough examinations, performed at regular intervals. Two annexes conclude the standard: an example of preliminary design information is given in the first while the second provides an example of a typical wind speed calculation report.

We expect the standard to be used by manufacturers and installers of edge protection systems as well as by architects and surveyors, civil and structural engineers, facility managers, and end-user clients. It will also be sought by fall protection and work-at-height specialists as it provides invaluable information for ensuring the safety of those working at height.