The Dangers of Working at Height - and how to mitigate them

Working at height is an inherently dangerous activity, which is why there are multiple regulations around the practice. The main concerns are falls and falling objects. Knowing the risk factors and mitigating against them are crucial.

Roofs

There are three types of roof that present particular working at height risks.

Fragile roofs - any roof that is not structurally sound enough to withstand the weight of a person and the equipment they're carrying, or any roof that may not have been able to withstand adverse weather. The risk of falling through the roof, or dislodging materials, needs to be assessed and mitigated.

Flat roofs - the risk on flat roofs is generally based on unprotected edges (see "Edges" section), where people, equipment, or other objects are at risk from falling unless secured.

Pitched (sloping) roofs - maintaining stability when working on a pitched roof can be a challenge, and slips are a big risk. When slipping down a pitched roof, workers or items may pick up speed, resulting in a greater and more damaging impact when they hit the ground.

Mitigation

Using the appropriate access equipment, protective equipment, and personal protective equipment (PPE) is vital to mitigating the risks of working at height.

Roof ladders and crawling boards (supported by load bearing structures) are generally the approach taken for fragile roofs, though access equipment may also provide a stable platform.

Guard rails and toeholds should be included when working with unsecured edges, and fall arrest equipment should be in place for workers.

Roof Lights and Panels

Many roofs include panels that are designed to let light through into the building. Often constructed out of lightweight materials that are fragile and easy to break, they represent a significant risk should a worker stand on them and fall through.

Due to their flat position on the roof, these types of panels can be difficult to see, often having gathered dirt and debris that makes them blend into the overall appearance of the roof.

Mitigation

Workers need to be made aware of the presence of roof lights and panels, and their location, so they are able to avoid them. Some are covered and guarded, but many are not.

Unsecured Edges

When working at height, unguarded edges are a significant danger, not only to workers who could fall, but also due to the risk of falling objects injuring people or property below.

Mitigation

Roofs, walkways, access platforms, and scaffolding should have appropriate measures in place before work commences. Guard rails are a common choice to mitigate this type of risk. Personal Protective Equipment (PPE), such as a harness, may also be required.

Weather Condiitions

Weather conditions can cause serious risks for working at height. Strong winds are a particular concern, making access more dangerous. Access equipment could be compromised, workers could be made unstable, and loose materials could be blown around causing injury.

Heavy rain makes the possibility of slipping more likely, as does snowfall and icy weather. Cold conditions also reduce feeling in the extremities (hands and feet). Numbed fingers can make completing work safely difficult, while cold feet can increase the chances of slipping or missing a step.

Mitigation

While shelters and PPE can reduce a small proportion of the risk, if adverse weather will affect the work, it should be postponed until weather conditions improve.

Safety First

Whenever you, or someone working for you, undertakes work at height, you should complete a risk assessment that covers the dangers applicable to your specific scenario, and put in place the appropriate measures to avoid or limit those risks.

Wherever possible, you should first try to avoid working at height. Where it is unavoidable, use the right measures to prevent falls. If the risk of a fall cannot be eliminated, use the right measures to minimise the distance and consequences of a fall.