Enhancing health and safety: Essential controls for managing inclement weather risks for high-risk activities in construction

Introduction:

The increasing effects of global warming are leading to more frequent and unpredictable adverse weather. The severity of these conditions is becoming more pronounced, with heavy and continuous rainfall, high winds, and plummeting temperatures in some parts of South Africa. Contractors must adapt health and safety (H&S) control measures to these changing conditions, as current controls may not be sufficient to maintain a safe work environment. Therefore, the article seeks to highlight proactive ways in which increased controls for high-risk activities can aid in reducing (H&S) risks during construction.

Proactive planning and programming for health and safety (H&S) during inclement weather is not just a suggestion; it’s an absolute necessity. This approach is crucial to ensure the safety of all personnel involved in construction activities.

The construction managers’ construction programme is a crucial tool that could help identify where increased control measures are required. When regularly updated based on local weather patterns, this programme becomes an early warning system for adverse impacts on construction activities. It assists with intelligent scheduling, reducing H&S risks, costs, time, and quality, and drafting the programme highlights increased risks during winter months. It is an early warning indicator for planning for inclement weather by improving health and safety controls. The construction programme can also aid in the form of mitigating specific activities; for example, high-risk activities that have a direct impact on the safety of employees, such as roofing, working on and from scaffolding, lifting operations, and excavation work, can be scheduled in such a manner to be performed outside of winter months significantly reducing the risks to workers and public that adverse weather may have however, this may not always be possible and practicable. Therefore, the early identification of increased control measures may be required. The construction manager should develop and update the programme with the health and safety officer to garner any pertinent input regarding additional controls that may be necessary, planned for, or procured.

Here are some insights into proactive (H&S) planning concerning certain high-risk activities that contractors should consider:

Excavations work
During winter, the risk of collapse and soil erosion in winter rainfall areas is significantly increased as heavy and continuous rainfall may weaken the side slopes and embankments of the excavation or an increased rise in the water table, causing underground water to seep through and further undermine the excavation, impacting its stability. Both heavy continuous rainfall and a high-water table can cause the excavation to fill up entirely to the top of the excavation, creating a pool-like scenario’ placing severe strain on the excavation walls and introducing a risk of drowning for workers and the public.
Dewatering methods are crucial for alleviating the pressure exerted on side walls by water build-up during heavy rainfall in the excavation. Dewatering can be done using a submersible pump, horizontal dewatering, and gravity drainage, among other methods that are not limited to.
Increased shoring and bracing measures may be required as the initial depth at which shoring and bracing are placed may be inadequate; for example, the risk assessment control measures may specify that shoring and bracing are only required at 1.5 metre depths; however, due to increased rainfall and water table, the new depth for shoring may need to be adjusted to 1 metre during winter months.
Redesign and increased strengthening of shoring or bracing may be required due to weather conditions, thus highlighting the importance of hazard identification and risk assessment (HIRA) to accommodate the change in conditions, specifically in winter.
Geotechnical reports are to be consulted for increased controls that may have been specified for winter months, and further inspections by the geotechnical engineer may be needed to reassess the excavation condition during and after inclement weather conditions.
Where rainfall excavations have become a ‘pool-like scenario,’ additional controls must be considered to reduce the risk of drowning, such as life jackets (PFDs), warning signs depicting the risk of drowning, edge protection, fall restraints, and prevention equipment.

Working on and from scaffolding
The risk of working at heights or from a fall-risk position is significantly increased. Heavy and continuous rainfall and high winds create slippery surfaces and instability for workers and structures, particularly when accessing and walking on scaffolding platforms, increasing the risk of falling. Working at heights during element weather should be avoided following controls determined in the fall protection plan to minimise this risk; however, additional control measures may be considered:
A competent person should increase scaffolding inspections before and immediately after inclement weather, as specified in SANS 10085-1. Further inspections may be required during inclement weather at specified intervals to ensure the stability of the structure itself for any change in condition in the interest of public safety in areas with high public traffic.
Removing or securing components any loose scaffolding components, such as access ladders, that may be dislodged during inclement weather.
Wiping down access ladders and scaffolding platforms with dry cloths before returning to and utilising scaffolding.
Dismantle scaffolding as reasonably practicable in anticipation of adverse inclement weather. This must be considered where inclement is forecasted for continuous days or weeks.
Consult the scaffolding designer regarding increased controls related to stability to accommodate all types of inclement weather.

Roof work
The risks associated with roof work are significantly increased during winter; however, they should be avoided during inclement weather, and contractors should accommodate any sudden change in weather. However, additional control measures may be considered.
Utilise a wind meter to monitor high wind speeds/knots and wind gusts and establish a safe working speed. Wind readings should be recorded daily, at least every hour, as otherwise specified in the fall protection.
Roof sheeting in progress should be adequately secured against sudden wind uplift, precisely where the installation is incomplete. Loose sheets are to be securely tied down, not just bricks placed on them.

Lifting Operations
The risk of lifting operations significantly increases during winter and should be avoided and creased if there is a sudden change in weather; however, additional control measures may be considered:
Ground conditions should be inspected more frequently during and after inclement weather before proceeding with a lift, as they may weaken during heavy rainfall due to water accumulation. Alternative bases may increase stability.
Additional lighting may be required as visibility may be low during inclement winter.
As mentioned above, a wind meter should be introduced over and above the crane’s meter. Lifting and rigging plans and procedures should determine safe working speeds.
Rely on pre-determined, best-practice banksmen signals if two-way radio communication is impacted due to the weather.

The above controls should be considered as they highlight the importance of proactive planning and the need for continuous Hazard Identification Risk Assessment (HIRA), which should accommodate for increased risk during winter and additional control measures that may not have been previously considered. It is important to note that each geographical location has unique hazards and can be impacted differently during winter; therefore, the reliance on predetermined risks could be fatal as adverse weather constantly changes in lieu of global warming. Other risks and increased controls to be considered during winter are cold stress, hysteria, and workers’ fatigue; equipment and machinery malfunction of electronics; and permanent structural and temporary structures’ integrity.

Disclaimer: The article is an opinion and awareness piece to promote H&S considerations during winter and is not to be utilised as a definitive or prescriptive guideline.