When we work on a roof more than two meters above the ground, there are a number of risks we need to consider, assess, and learn how to avoid in order to work safely and with confidence, including risks in photovoltaic systems.
What Is a Roof?
Starting with the basics, a roof is the surface that covers a building or industrial facility to protect it from weather.
Types of Roofs
There are three types of roofs according to their strength, and within each they can be classified by roofing material.
Fragile roofs are those that cannot support foot traffic or the storage of materials without installing or using auxiliary means or additional safety elements.
| Roof type | Roofing material |
|---|---|
| Fragile | Translucent polyester Translucent polycarbonate Fiber cement Translucent cellular polycarbonate Methacrylate roof domes |
| Light | Trapezoidal or mini-corrugated metal sheet Sandwich panel Deck roof Standing seam |
| Other | Tile over a compression layer and “partition walls” Concrete slab and floor slabs |
We should clarify that all fragile roofs are light roofs. That is, in a sandwich panel, for example, we can find translucent panels or roof domes.
Roof Work
Many kinds of work are done from a roof, whether for maintenance, repair, or the installation of different elements.
- Insulation and waterproofing.
- Repair of leaks or seepage.
- Replacement of roof tiles or sheets.
- Joint sealing.
- Removal of asbestos roofing or replacement with other materials.
- Installation or maintenance of solar panels.
- Cleaning of chimneys or gutters.
- Repair or replacement of antennas.
- Snow removal.
What Risks Exist When Working on a Roof?
Carrying out this type of work involves risks due to the characteristics of the roofing material, the height at which the work is done, or inclement weather.
The main causes of workplace accidents on roofs are the following:
- Climbing up or down using portable ladders or unprotected fixed ladders.
- The roof sheet breaking as the worker passes over it.
- Stepping directly on low-strength roof domes or interior skylights.
- Inclement weather (wind, rain, snow, humidity…).
- Poor condition of the upper surface of the sheet or anchoring area.
These falls from height can be avoided, as long as we use the appropriate safety devices and systems for each job.
Safety Devices on a Roof
When we work on a roof we must bear in mind that a risk exists, and therefore we must work out how to avoid it. To do so, we must select the roof perimeter protection that best suits our project.
The first option is to use collective protection that guarantees safety across the entire surface where the worker will be, such as safety guardrails. With these safety systems, we would prevent falls off the roof.
Another option is rigid or cable lifelines. These devices are used with a fall arrest harness and its corresponding accessories (carabiners, connectors, and rope grabs).
On fragile roofs where we find skylights or roof domes, safety nets, such as PIGNUS, should be installed. Depending on the translucent panel, we will choose among the different types of net.
