Occupational Health and Safety & Snow-Covered Roofs: What Are the Risks?

Winter is here in Canada. However, behind this beautiful white coat also hide significant occupational health and safety challenges for organizations.

The tasks involved in preventive building maintenance in winter, from monitoring snow loads to clearing snow from roofs, involve a particularly high level of risk. Despite this, it is not uncommon to find that these risks are often underestimated or misjudged within organizations.

Our team has compiled all the information you need to understand the impact of these occupational health and safety risks, as well as the solutions you can consider to ensure the safety of your personnel during the winter.

Occupational Health and Safety Risks Associated With Preventive Maintenance of Buildings in Winter

First of All, What Does Winter Building Maintenance Involve?

1. Snow monitoring:
   This involves climbing onto the building several times a winter to validate the level of snow load on the roof. This may involve visual validation or random weighing of the snow load.
   
   
2. Partial or total snow removal from the roof: 
   Some organizations choose to entrust snow removal from the roofs of their buildings to their own employees during the winter. This means they have to climb onto the roof to push snow off the roof, particularly in critical areas.
   
   Important: whether your snow removers are your own employees or external subcontractors, you are still responsible for your buildings, and must therefore ensure the safety of all those who will be on your roofs in winter.
   
   

Risks Faced by Workers

Unsurprisingly, these tasks entail health and safety risks for workers, who expose themselves to a high risk of workplace injury or, worse still, death.

The following is a description of the risks and their potential causes: 

Entrusting Roof Snow Removal to Your Employees Is Not Without Risk!

If you have chosen to entrust snow removal from your buildings' roofs to your own employees, you should be aware that they may not have the occupational health and safety knowledge required for working on the roof, compared with qualified external snow removers who are professionally trained to avoid such risks.

In other words, there's nothing wrong with offering this task to your in-house teams. But you need to make them aware of the risks involved, while ensuring their protection at all times.



What Work Methods Are Available to Safely Clear Snow From the Roof?

In this section, we summarized the information on the CNESST (The Commission for Standards, Equity, Health and Safety at Work in Quebec) website concerning the safe removal of snow from different types of roofs.

First of all, the preferred working method depends on the climatic conditions, the quantity of snow and the place of work (location, dimensions, slope, accessibility, solidity and grip). It will also need to be adapted to different types of roofs, particularly old, recently insulated roofs and flat roofs with obstructions.

Minimum Safety Measures for Working in High Areas

Workers must be protected against falls whenever they are exposed to a fall of more than 3 m (118 in).

To work in high areas, it is important to:

• Use guardrails (or a warning line)
• Offer personal protective equipment (PPE) to all responders who must go to your roof, such as a safety harness with energy absorber and a fall arrest connection, securely attached to an anchor point of the right strength using a 16 mm nylon rope and a slider
  
• Encourage the use of personal lifting devices that allow people to go on the roof more safely, such as a lifting platform, a cherry picker or even a mast articulating boom lift
  
  

Snow Removal From a Flat Roof

• Adequately circumscribe the snow dumping area and prohibit access to it
• Establish a snow dumping area protected by a guardrail at the edge of the roof
• Establish a 2 m (6.56 ft.) buffer zone around the roof with a warning line. This zone will not be cleared of snow.
• Complete the layout with a U-shaped discharge area approximately 2.5 m (8.2 ft.) wide, protected by a guardrail, at the edge of the roof.
  
  

Snow Removal on a Sloping Roof

On sloping roofs, we recommend snow removal starting at the top and working towards the bottom of the roof, in addition to providing fall protection.

Starting snow removal from the bottom of the roof can cause large pieces of snow from the top of the roof to detach and slide off, creating the risk of a fall and subsequent burial under the snow. Sudden detachment of large masses of snow can occur when the roof covering is smooth, as in the case of sheet metal, for example.

 

3 Measures to Maximize Your Employees’ Health and Safety on Rooftops

To maximize the health and safety of your employees, especially those responsible for preventive building maintenance, it's essential to implement rigorous preventive measures. 


1. Implement a Snow Monitoring and Response Plan to Properly Manage Snow on Your Buildings in Winter

A snow monitoring and response plan will enable you to document all the information concerning snow monitoring and management activities in your organization, from the recurring tasks to be carried out to the protocol to be applied in the event of a collapse, including a description of the roles of each stakeholder.

Our team of structural engineers has put together a comprehensive guide to help you design your own snow monitoring and response plan quickly and easily. Download it for free right here: