As we saw in the post on collective protection, the most widely used and best known are edge protection guardrails. Within these we have two types according to the applicable standard:
- Edge protection guardrail. UNE-EN 13374 applies
- Guardrail for means of access. UNE-EN 14122 applies
Today we will talk about the former, explaining the basic requirements they must meet and the specific requirements demanded for each class of guardrail.
Requirements for Edge Protection Guardrails
The basic requirements define which components the system must include. It must consist of at least a main rail and an intermediate rail or intermediate protection, and it must allow a toe board or kick plate to be attached.
- Main rail. The distance between the top of the edge protection and the working surface must be at least 1.0 m, measured perpendicular to the working surface.
- Toe board or kick plate. The top edge of the toe board must be at least 150 mm above the working surface. The toe board should be designed to avoid gaps between it and the normally horizontal working surface. If there are gaps, a sphere with a diameter of 20 mm must not pass through them.
Guardrail Classes
The UNE-EN 13374 standard sets out a series of additional requirements depending on the class of guardrail concerned:
Class A Edge Protection System
The inclination of a class A edge protection system must not deviate from the vertical by more than 15º.
If an intermediate rail is provided, any opening must be sized so that a sphere 470 mm in diameter cannot pass through the protection. If there is no intermediate rail, or if it is not continuous, the edge protection system must be sized so that a sphere with a diameter of 250 mm cannot pass through it.
When it is not possible to verify the load requirements by calculation, the static load tests specified in the UNE standard, clause 7.4, must be carried out for class A edge protection. In this case, to comply with the standard, specific strength conditions must be met according to the applied load and deflection.
Class B Edge Protection System
The inclination of a class B edge protection system must not deviate from the vertical line AC by more than 15º.
Any opening in a class B side protection must be sized so that a sphere 250 mm in diameter cannot pass through the protection.
If it is not possible to verify the load requirements by calculation, the static load tests specified in the UNE standard, clause 7.4, must be carried out for class B edge protection. In this case, to comply with the standard, specific strength conditions must be met according to the applied load and deflection.
In addition, class B edge protection must withstand the dynamic loads specified in clause 6.
Class C Edge Protection System.
The inclination of the side protection must lie between the vertical (line AC) and the perpendicular to the surface (line BC). Openings in class C edge protection must be sized so that a sphere with a diameter of 100 mm cannot pass through the protection.
Class C edge protection must provide resistance to the dynamic loads specified in clause 6.4.3.
Legend
- AC vertical line
- BC line perpendicular to the working surface
- Angle of inclination of the working surface.
- Angle between line AC and the edge protection (the maximum for class B is 15º)
Manufacturing Materials According to EN-13374
Regarding the materials used to manufacture guardrails, the standard states that the materials used must meet the requirements defined in the European standards. Materials must be sufficiently strong and durable to withstand normal working conditions. They must be free of impurities and defects that could affect their satisfactory use.
The most common materials are:
- Galvanized steel.
- Aluminum.
- Wood.
- Counterweight material.
These must be solid. Granular or fluid materials such as sand or water must not be used. Each counterweight must be able to be perfectly secured against accidental displacement.
Now that we have covered the basic and specific requirements that edge protection systems must meet according to their class, in upcoming posts we will discuss the calculations and test methods of the UNE-EN 14122 standard.