The latest 2019 statistics from the Health and Safety Executive (HSE) revealed that falls from heights remain the number one cause of workplace fatalities, increasing from 35 people in the previous reporting year to 40 people. In a timely move, new working from height guidance by the Association of Technical Lightning & Access Specialists (ATLAS) was issued in July 2019, entitled, “Wind Guidance Note for Working at Height”. ATLAS has considerable experience and expertise in this sector, having played a role in the provision of health and safety guidance to companies in the lightning protection and specialist access at height sectors since 1946.
What is the purpose of the new ATLAS guidance?
Regulation 4 of the Work at Height Regulations 2005 (WAHR 2005) imposes a legal duty on employers to make sure that work undertaken at height is properly planned, appropriately supervised, and practicably safe. The ATLAS guidance was written to assist site staff, employers and clients further “understand the importance of taking wind effects into account in their everyday assessment of activities whilst working at height”, in accordance with the WAHR 2005. Specifically, it aims to:
- Improve the understanding of wind and its behaviour;
- Provide an on-site point of work risk assessment, and;
- Provide supporting information and tools for measuring wind and recording, including links to sources of further information.
What does ATLAS guidance recommend?
The guidance outlines a number of core concepts and considerations relating to the wind when working at height in the UK, including the following (note this is not an exhaustive list of the points made):
- Wind gusts (rapid variations in wind speed) are higher inland and are typically 60% higher than the average (mean) wind speed; in cities, this can be up to 100% higher.
- Northerly wind gusts are generally stronger than those from the south.
- When assessing risks, local topological features (the changes in land surfaces such as hills, rivers, and valleys) and wind direction must be considered.
- Account should always be taken of the effect of funnelling, whereby wind blowing between structures can cause wind in some parts of a site to accelerate, creating ‘windy corners’.
- The lee side of buildings or structures (sheltered side) may provide protection when working from height.
- The windchill effect should also be considered. It is important to consider the ‘feels like’ temperature on windy days, as this can cause human body temperatures to lower to dangerous levels. When assessing this risk, it will be necessary to bear in mind the wind direction (i.e. northerly wind, especially in winter, creates lower ‘feels like’ temperature compared to the actual air temperature).
- Site weather conditions should always be formally recorded in the site diary.
The guidance refers to the wind code BS EN 1991-1-4:2005+A1:2010 which specifically deals with how to measure the impact of natural winds on loaded areas of buildings under construction. The code which is intended for use by construction site managers, architects and building contractors, and those studying architecture and construction explains how the wind changes with height. A wind speed of 10m/sec at 10m of height (classified as wind force 5 – a fresh breeze) could be 11.4m/sec at 50m and 12m/sec at 100m (both classified as wind force 6 – a strong breeze). So while wind at ground level may be considered safe to work at height, it may not be the higher the worker goes (the HSE recommend not working on a roof if the wind is in excess of force 5 or 23 mph).
What does the guidance recommend in respect of high wind speeds?
The guidance makes it clear that regardless of the size of the job, responsibility lies with the individual in charge of the project, but there must be close coordination with the client. Specialist measuring equipment such as wind-speed indicators, weather stations, and anemometers, can offer some assistance when assessing site risk and making decisions for working at height, but this is of no value for the prediction of future wind conditions. As such, if there is a potential for high winds, continuous weather monitoring must be undertaken, including:
- Considering the time of year and its history
- Watching the various media and broadcasting channels for the weather forecast (in advance of work starting)
- Using information from the site (where available)
- Once work has started, continuous monitoring of the weather as shown on broadcasting channels and/or online data sources
- Setting up a portable weather station either hand-held or fixed (this will be especially important if there are site restrictions on the use of mobile phones)
- Recording findings to demonstrate that a point of work risk assessment has been carried out, and delays to job completion are justified in the interests of safety
Any company which requires its workers or contractors to work outside at height must establish a robust and safe system of work which takes the wind into full consideration. The wind must be factored into all decision making from the earliest planning stages, through initial site preparations and the carrying out of work. The HSE provides a great deal of information on ways in which workers can be made safe when working at height, including the use of personal protective equipment (PPE) such as safety harnesses with energy-absorbing lanyards attached to a suitable anchor point to arrest a fall.
When it comes to worker safety, leave no stone unturned. Prioritising project schedules over worker safety can lead to fatalities, near misses, severely delayed projects if investigations are required, claims for a workplace injury, and significant damage to your organisation’s reputation.
Tanveer Qureshi specialises in health and safety, food hygiene, and environmental law. If you require legal representation, please contact Tanveer directly at email@example.com or via his chambers, 4-5 Gray’s Inn Square. for more about Tanveer or to subscribe to his newsletters, please go to www.tqlegal.co.uk