With two recent, notable heatwaves and drought warnings becoming part of the daily narrative in the UK, we take a look at how fire engineering needs to respond as we face increasing numbers of extreme weather events around the world[1].
Such weather events may seem out of our control but from a fire engineering perspective there is much work going on to develop strategies that help us to adapt, some looking at the way we design and adapt our buildings, infrastructure and landscapes, others focus on building community resilience, with some of this work forming part of our activities under the People Pillar of the IFSS Decade of Action for Fire Safety[2].
Heatwaves are particularly deadly in places like the UK, parts of Northern Europe, and the Pacific Northwest of the USA, where extremely hot weather is rare and air conditioning uncommon, making hot weather a bigger concern for the health of the elderly, disabled, and others unable to shelter in cooler places[3]. Indeed, statistics indicate that extended periods of hot weather result in more excess deaths[4] than other any other kind of weather-related emergency.
Engineering new building systems
Urban areas may be more prone to high temperatures due to the urban heat island effect[5]. This effect results from the large heat sink created by building materials and paving, which accumulate and radiate excess energy absorbed during daylight hours. This prevents urban areas from cooling as much after nightfall as they would otherwise.
In areas where air conditioning is more common, cooling increases electricity demand at a time when energy systems are already under pressure. The combination of exceptionally high prices for energy or the potential risk of supply interruptions can prompt people to use make-shift arrangements for light and power, which introduce new potential fire risks into homes and businesses. Camping gas appliances, generators or barbeques also pose a risk of carbon monoxide poisoning as they are not designed to be used in enclosed spaces.
Fire engineers need to be proactively engaged in developing future resilience plans for buildings and infrastructure in both rural and urban areas to consider options for risk mitigation and community protection.
A burning issue
Extended periods of high temperature are often accompanied by high winds. This combination of extreme weather dries out vegetation, making grasslands and vegetation more susceptible to ignition. The recent record-breaking heatwave in the southeast of the UK, led to unprecedented numbers of incidents.[6]
Long periods of dry weather also mean increased risk from ignition sources not often associated with starting wildfires, such as reflected or concentrated sunlight from mirrors or glass, sparks from lawn mower blades striking rocks, hot particles ejected from the exhausts of small internal combustion engines, and catalytic converters or car exhausts.
Residents experiencing dehydration or heat stress may also be more prone to poor decision making. The consumption of alcohol may also increase sharply during heat waves, which makes all sorts of civil unrest and mishaps more likely, including fires.
In some parts of the world, periods of hot weather can cause thunderstorms capable of producing damaging winds, hail and lightning. These systems may be brief but are often quite intense and can result in significant property damage or indeed fires caused by lightning strikes.
Many other types of municipal infrastructure, such as roads and rail lines, may be adversely impacted by extremely hot weather due to expansion, deformation or softening.
As we have seen through wildfire incidents around the world, such fires can pose a serious threat to homes, especially buildings with combustible exterior cladding, wood decks, fences, textile awnings, exterior storage of combustibles such as firewood, and landscaping. Communications and awareness raising of the risks are paramount.
On the frontline
Firefighters typically experience a sharp increase in calls during heat waves due to medical emergencies, vegetation fires and fires resulting from overloaded electrical services.
Firefighting in these situations presents unique challenges. During extended high-temperature events, excessive demand for water can deplete supplies available for firefighting.
Ultimately, firefighting during extreme weather events, is taxing both physically and mentally. Extra attention to firefighter safety, especially hydration, is needed. Firefighters may require extended periods of rehab or recovery following physical exertion.
The IFE is working with members, academics and partners to explore innovations and the kind of equipment that can better protect firefighters and also offer solutions when water resources are constrained.
[1] https://www.wired.com/story/extreme-weather-2022-just-getting-started/
[2] https://www.ife.org.uk/home/news/details/blog-why-understanding-people-is-vital-to-fire-engineering
[3] https://www.newscientist.com/article/2331349-40c-heatwave-may-have-killed-1000-people-in-england-and-wales/
[4] https://www.kentonline.co.uk/news/national/more-than-2-500-excess-deaths-as-summer-heatwaves-take-toll-17176/
[5] https://www.epa.gov/heatislands
[6] Londoners urged to take action during second heatwave as new data shows unprecedented increase in grass fires | London Fire Brigade (london-fire.gov.uk)