As we have mentioned in some of our posts, according to Law 31/1995, on Occupational Risk Prevention, when protection against possible accidents is needed, collective protection takes priority over personal protection.
This means that, in our case, when providing safety on the various roofs or access points, we will use systems that protect users in a general way.
A good solution is edge protection guardrails; with these systems we ensure the collective fall protection mentioned above.
As a reminder, these systems are manufactured, tested, and installed under the standard UNE-EN 14122-3:2016 Permanent means of access to machinery. Part 3: Stairs, stepladders and guardrails.
Classification of Guardrails
As we already know, on each project we may encounter different requirements that call for the installation of one system or another.
In the case of perimeter protection guardrails, the design will vary depending on the type of roof or access to be protected. There are many solutions available for these systems; mainly, we can distinguish two needs to consider.
On the one hand, the type of environment where it will be installed, which will define the type of material to choose from:
- Aluminum, with or without anodizing, painted.
- Stainless steel.
- GFRP.
Or, the place and use where they will be installed, where we can choose among the different guardrail types available on the market, referring to their fastening system on the roof.
Today we are going to focus on this last aspect, looking at each of the existing types and their corresponding features and functions.
Types of Guardrails
To understand this section well, let us imagine an industrial roof. The first thing we must consider is its design, its slope, its finish, what requirements the material selected for its construction implies, and whether or not it has already been waterproofed.
All this information helps us decide on one fastening system or another, since a sandwich panel roof, which allows these systems to be fastened to it, is not the same as a waterproofed TPO roof, a green roof, or an inverted deck roof; in these cases, as we will see later, which system best fits our needs.
Counterweighted Guardrails
This type of guardrail is the right solution for roofs where no fastening can be made, as we mentioned before: roofs with a TPO, deck, or green finish no longer accept anchors once completed, because doing so would break the waterproofing of the roof. A floor-mounted installation could be done, but it would entail unnecessary extra costs to waterproof the guardrail’s anchor elements again.
Another case is when we are looking for a temporary solution, a system that we can remove once the work on the roof has been completed; in these cases, the counterweighted type is the best option. Each manufacturer will specify the number of counterweights to place, depending on the installation location and the standard to be met.
Floor-Mounted Guardrails
When we have concrete roofs or any other material that allows elements to be fastened to it, we use this type; depending on the manufacturer, the anchor bases will differ for each type.
In our case, we have designed a base that covers all installation types, so in each case we will consult the manufacturer or installation company about which type of anchor is needed in our situation. In these cases, we must also make sure that, once the fastening is done, the roof remains free of leaks.
Wall- or Parapet-Mounted Guardrails
In this type, floor mounting is not permitted because of the type of roof we are dealing with, but it has elements such as walls or the roof parapet itself, to which our fastening system can be anchored without a problem.
Sheet-Metal-Mounted Guardrails
Lastly, there are two variants within this type: the anchor elements can be fastened to single sheet metal, also known as trapezoidal metal sheet, or to sandwich panel.
In these two cases, the roof allows elements to be fastened to it, always bearing in mind that once these systems are fastened, as with floor mounting, the roof must be waterproofed in the areas where the hardware was drilled, either with sealing gaskets or with liquid products that seal those holes.
Recommendations
As we noted, each situation will need one type of solution or another. It is important to point out that, besides these types, we may encounter special situations that require a custom solution specific to that roof, whether because of its finish, elements that interrupt the usual fastening method, and so on.
That is why, before deciding on the anchoring system to use, you should contact the manufacturer or installation company so they can guide us on the type of solution we need, through their data sheets, manuals, and other documentation.