Humans light 85% of bushfires, and we do virtually nothing to stop it


Janet Stanley, University of Melbourne

It’s hard to comprehend why someone would deliberately light a bushfire. Yet this behaviour regularly occurs in Australia and other countries. We would go a long way to preventing bushfires if we better understood this troubling phenomenon.

Experts estimate about 85% of bushfires are caused by humans. A person may accidentally or carelessly start a fire, such as leaving a campfire unattended or using machinery which creates sparks. Or a person could maliciously light a fire.

This criminal behaviour is not widely recognised or understood by the public, fire authorities or researchers. This means opportunities to prevent bushfires are generally being missed and resources devoted to tackling the cause are far from commensurate with the devastating consequences.

The 2013 fire at Wallan, Victoria, was thought to be deliberately lit.
MARK DADSWELL/AAP

Profile of an arsonist

Research has shown about 8% of officially recorded vegetation fires were attributed to malicious lighting, and another 22% as suspicious. However, about 40% of officially recorded vegetation fires did not have an assigned cause. When unassigned bushfires were investigated by fire investigators, the majority were found to be maliciously lit.

But official fires are just the tip of the iceberg: the actual number of bushfires in Australia is thought to be about five times that recorded. Virtually none of these unrecorded fires are investigated.

Young men comprise the largest group of people who maliciously light fires. These youth are usually troubled, likely to have absent fathers and little home supervision. They are likely to have experienced child abuse and neglect and associated with an antisocial peer group. Lighting fires may give a feeling of excitement, defiance and power, or it may be an expression of displaced anger. Some offenders have an intellectual disability.




Read more:
A surprising answer to a hot question: controlled burns often fail to slow a bushfire


Offenders may make no attempt to extinguish the fire, and give little consideration to the consequences. Some may have no feelings of remorse or fear of punishment. Others may never have intended to create such wide devastation.

Older males who light malicious fires also have a history of social and educational disadvantage, poor family functioning in childhood, low self-esteem, and often a pathological interest in fire. However the older the person gets, the less likely they are to light fires.

Convicted Black Saturday arsonist Brendan James Sokaluk arriving at the Supreme Court in Melbourne.
Julian Smith/AAP

So why don’t we talk about arson?

During last week’s east-coast bushfire crisis, a handful of news reports covered people lighting fires. They include a teenager who allegedly lit a Queensland bushfire that razed 14 homes, and a man charged with starting a Sydney fire by letting off fireworks.

Media attention on a fire’s cause is generally scant and the public rarely hears much beyond initial charges being laid. This is in stark contrast to blanket news coverage of the consequences of bushfires.




Read more:
Grattan on Friday: When the firies call him out on climate change, Scott Morrison should listen


A staggeringly low apprehension and conviction rate for offenders – less than 1% – is a further barrier to public awareness of the problem. Conviction rarely leads to a substantial punishment.

Fire brigades in most states offer a limited education course for some children who light fires, usually led by volunteers. But there are few targeted treatment programs for those who light bushfires.

Firefighters near Sydney in November 2019 conducting controlled burning – a common fire mitigation method.
Jeremy Piper/AAP

Rethinking the bushfire problem

Rather than tackling the cause of the problem, the major response to bushfire in Australia is mitigation. This largely involves one blunt approach: hazard reduction burns to reduce bushfire fuel loads. This is an increasingly difficult task as climate change makes weather conditions more unsuitable for controlled burns.

This business-as-usual approach has not halted the upward trajectory of bushfire ignitions.




Read more:
12 simple ways you can reduce bushfire risk to older homes


A much greater focus on prevention would require a significant rethinking of the bushfire problem. This would include collaboration between government, business, non-government organisations, communities and others.

Victoria’s Gippsland Arson Prevention Program provides a promising model. Through public education, media engagement and other means, it informs communities on how to help prevent arson. The committee includes Victoria Police, government and fire authorities and local power generators.

In one example of an on-the-ground response, local authorities organised the removal of dumped cars, which are commonly seen by bored and troubled youth as an invitation to start a fire.

Arson prevention also includes addressing long-term problems such as youth disadvantage and unemployment, especially in rural-urban fringe areas where most human-lit fires occur.

Shorter-term approaches include providing support and treatment to at-risk youth, and situational crime prevention such as good lighting and cameras in places vulnerable to fire lighting.

We must open up a society-wide discussion of bushfire prevention, which includes listening to local communities about what they value and what can be done about the problem. As climate change worsens – and bushfires along with it – a radical rethink is required.The Conversation

Janet Stanley, Associate professor/Principal Research Fellow, Melbourne Sustainable Society Institute, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How does poor air quality from bushfire smoke affect our health?


Brian Oliver, University of Technology Sydney

New South Wales and Queensland are in the grip of a devastating bushfire emergency, which has tragically resulted in the loss of homes and lives.

But the smoke produced can affect many more people not immediately impacted by the fires – even people many kilometres from the fire. The smoke haze blanketing parts of NSW and Queensland has seen air quality indicators exceed national standards over recent days.

Studies have shown there is no safe level of air pollution, and as pollution levels increase, so too do the health risks. Air pollution caused nine million premature deaths globally in 2015. In many ways, airborne pollution is like cigarette smoking – causing respiratory disease, heart disease and stroke, lung infections, and even lung cancer.




Read more:
Firestorms and flaming tornadoes: how bushfires create their own ferocious weather systems


However, these are long-term studies looking at what happens over a person’s life with prolonged exposure to air pollution. With bushfire-related air pollution, air quality is reduced for relatively short periods.

But it’s still worth exercising caution if you live in an affected area, particularly if you have an existing health condition that might put you at higher risk.

Air quality standards

The exposure levels will vary widely from the site of the fire to 10 or 50 kilometres away from the source.

The national standard for clean air in Australia is less than 8 micrograms/m³ of ultrafine particles. This is among the lowest in the world, meaning the Australian government wants us to remain one of the least polluted countries there is.

8 micrograms/m³ refers to the weight of the particles in micrograms contained in one cubic meter of air. A typical grain of sand weighs 50 micrograms. When people talk about ultrafine particles the term PM, referring to particulate matter, is often used. The size of PM we worry the most about are the small particles of less than 2.5 micrometres which can penetrate deep into the lungs, called PM2.5.

People with pre-existing medical conditions are at highest risk.
From shutterstock.com

To put this in perspective, Randwick, a coastal suburb in Sydney which was more than 25km from any of the fires yesterday, had PM2.5 readings of around 40 micrograms/m³. Some suburbs which sit more inland had readings of around 50 micrograms/m³. Today, these levels have already reduced to around 20 micrograms/m³ across Sydney.

We’re seeing a similar effect in Queensland. Today’s PM2.5 readings at Cannon Hill, a suburb close to central Brisbane, are 21.5 micrograms/m³, compared with 4.7 micrograms/m³ one month ago.

A number of health alerts were issued for areas across NSW and Queensland earlier this week.

While these numbers may seem alarming compared to the 8 microgram/m³ threshold, the recent air pollution in India’s New Delhi caused by crop burning reached levels of 900 micrograms/m³. So what we’re experiencing here pales in comparison.

Bushfire smoke and our health

However, this doesn’t mean the levels in NSW and Queensland are without danger. Historically, when there are bushfires, emergency department presentations for respiratory and heart conditions increase, showing people with these conditions are most at risk of experiencing adverse health effects.

Preliminary analysis of emergency department data shows hospitals in the mid-north coast of NSW, where fires were at their worst, have had 68 presentations to emergency departments for asthma or breathing problems over the last week. This is almost double the usual number.




Read more:
After the firestorm: the health implications of returning to a bushfire zone


One study looked at the association between exposure to smoke events in Sydney and premature deaths, and found there was a 5% increase in mortality during bushfires from 1994 to 2007.

But it’s important to understand these deaths would have occurred in the people most vulnerable to the effects of smoke, such as people with pre-exsisiting lung and heart conditions, who tend to be older people.

For people who are otherwise healthy, the health risks are much lower.

But as the frequency of bushfires increases, many scientists in the field speculate these health effects may become more of a concern across the population.

How to protect yourself

If you’re in an affected area, it’s best to avoid smoke exposure where possible by staying indoors with the windows and doors closed and the air conditioner turned on.

If you are experiencing any unusual symptoms, such as shortness of breath or chest pain, or just do not feel well, you should speak to your health care professional and in an emergency, go to hospital.




Read more:
How rising temperatures affect our health


Once the fires have been put out, depending upon the region, local weather conditions and the size of the fire, air quality can return to healthy levels within a few days.

In extreme situations, it might take weeks or months to return to normal. But we are fortunate to be living in a country with good air quality most of the time.The Conversation

Brian Oliver, Research Leader in Respiratory cellular and molecular biology at the Woolcock Institute of Medical Research and Senior Lecturer, School of Medical & Molecular Biosciences, University of Technology Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How a bushfire can destroy a home


Douglas Brown, Western Sydney University

Ten years after the devastation of Black Saturday, building design has largely been unrecognised as an area worthy of research. We have advanced our knowledge of the materials used in the construction of homes in bushfire-prone areas but we continue to use the design model of the suburban home.

This needs to change. An initial starting point is to consider the way previous bushfires have damaged and destroyed buildings.




Read more:
Where to take refuge in your home during a bushfire


Elements of a bushfire

A bushfire has five different elements: smoke, wind, embers, flames, and radiant heat (the latter two are collectively called the “fire front”).

Smoke and wind are usually present throughout a fire, but are particularly high when the fire burns at its most intense levels. Depending on the type of vegetation burning, isolated flying embers may arrive hours before a fire front. Intense ember attacks usually occur 15-30 minutes before a fire front arrives, and may persist for up to 8 hours after the fire front moves on.

Radiant heat at a level that makes it impossible to survive outside will persist during the passage of the fire front, which may last anywhere between 2 and 15 minutes. However, if consequential fires are ignited by the main fire front, the radiant heat may remain at non-survivable levels for much longer.

The smoke of a bushfire reduces visibility and can turn a bright day into night. A change in wind direction can renew a threat residents thought had already passed them.

How will a bushfire attack your home?

Most people would expect that the most destructive element of a bushfire is the fire front, but rather surprisingly that’s not the case. Ember entry and associated spot fires, rather than direct flame contact, accounts for 75-80% of homes destroyed by bushfires.

Embers can be large strips of burning bark, or a tiny spark as small as a pinhead, and depending on wind speed these can travel up to 10 kilometres ahead of the fire front.

Australian research over the past 75 years has revealed more than 20 different parts of a house and its surrounding area that are vulnerable to bushfire attack. Much of this knowledge has now been incorporated into a recently updated Australian Standard: Construction of buildings in bushfire-prone areas.

These guidelines aim to reduce the vulnerability of each part of a house, and thus make the structure as a whole more resistant to bushfire damage. The Standard applies across Australia for new homes and renovations.

The known building ignition points

The known weak parts of a building are referred to as the “building ignition points”. Several are considered below:

Roof cavity

In domestic homes the roof cavity is the large open space under the roof and above the ceiling. Embers in this space can cause fire to spread rapidly, making the whole building vulnerable to ceiling collapse.

Any gap in the roof, such as a poorly secured tile, can allow flying embers to enter. The burning crown of a nearby tree, pushed onto a roof by high-speed winds, can also ignite the house.

When people choose to shelter in their bathrooms they often forget the ceiling is particularly vulnerable there. It’s difficult to access a roof cavity with a fire hose, and extinguishing embers and fire invariably damages electrical wiring, plasterwork, and home contents.

Regular inspection and maintenance of roof elements can help reduce ember entry. Avoiding trees close to your house, and removing any overhanging branches, can also help reduce this bushfire risk.

Gutters

Overhanging trees can cause compacted leaf litter to build up in gutters. During a bushfire flying embers land in this material, catch alight and spread flames to combustible parts of the roof structure such as wooden facia boards, rafters, roof battens, and eaves.

It’s a good idea to clear out your gutters each year as part of seasonal bushfire preparation. Some people choose to wait until a bushfire is approaching to do this, but going onto your roof for the first time in semi-darknes while embers are flying at you can put you at risk, and endanger your life.

If you’re building a new structure you can consider extending the roof line and having a water collection system on the ground to remove the need for gutters.

Vents and weep holes

Together vents and weep holes allow for fresh air to pass through a building and for excess moisture to leave, reduce condensation and mould. They are necessary for our comfort and health, and maintaining the integrity of a building.

However in a bushfire these types of external openings can allow flying embers to enter the building and start spot fires. Having steel or other non-combustible mesh with small holes in front or behind vents and weep holes can reduce the bushfire risk while still allowing air and moisture to pass through.

Subfloors

Often houses constructed in bushfire-prone areas are built on a sloping block of land. The area under the building (the subfloor) is left open rather than being enclosed, and combustible materials are often stored there. The danger is similar in scale to embers in the roof cavity. When embers or flames take hold in this subfloor area they can spread under the entire building and allow the fire to move up.

Plants and mulched garden beds next to the home

Garden beds and timber steps near a house are a potential danger during a bushfire. Plants with dense foliage can burn intensely and cause radiant heat damage, cracking and imploding nearby windows and glass doors.

Garden beds which have been recently mulched can trap flying embers and spread fire to timber subfloors. It’s much better to have a non-combustible paved area next to your home, with pots containing either succulents or plants with thin foliage.




Read more:
How can we build houses that better withstand bushfires?


Deciding whether to stay and defend a home or leave early is a difficult and contentious choice. Hopefully, knowing more about some parts of your house which are most vulnerable to bushfire attack will make that decision easier.The Conversation

Douglas Brown, Casual Academic, Western Sydney University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The bitter lesson of the Californian fires



File 20181112 194485 2i4k8e.jpg?ixlib=rb 1.1
A firefighter in California. Firefighting is getting more and more expensive as fires get more destructive.
PETER DASILVA

David Bowman, University of Tasmania

California is burning, again. Dozens of peoples have been killed and thousands of buildings destroyed in several fires, the most destructive in the state’s history.

The California fires are just the most recent in a series of major wildfires, including fires in Greece in July this year that killed 99 people, Portugal and Chile in 2017, and Australia.

Why do wildfires seem to be escalating? Despite president Donald Trump’s tweet that the California fires were caused by “gross mismanagement” of forests, the answer is more complex, nuanced, and alarming.

What caused the California fires?

The current California fires reflect a complex mix of climate, social, and ecological factors. Fuels across California are currently highly combustible due to a prolonged drought and associated low humidity and high air temperatures. Indeed, it is so dry fires burn freely through the night. Such extreme weather conditions have the fingerprints of climate change.




Read more:
Wildfires in Mediterranean Europe will increase by 40% at 1.5°C warming, say scientists


Compounding the desiccated fuels are the seasonally predictable strong desert winds (the Diablo and Santa Ana) that help fires spread rapidly towards the coast.

Low density housing embedded in flammable vegetation has created an ideal fuel mix for these destructive fires. Having people scattered across the landscape ensures a steady source of ignitions, ranging from powerline faults to carelessness and arson, making fires a near certainty when dangerous weather conditions arise.

One of the fires burning in California.
MIKE NELSON

Decades of wildfire suppression have created fuel loads that sustain intense fires. That these fuels are burning in late autumn is even more alarming. Under severe fire weather forest fires can engulf entire communities, with fires spreading from house to house, and human communities turning into a unique wildfire “fuel”. Suburbs can burn at the rate of one house per minute .

The standard response to wildfires is to fight them aggressively, using a military-style approach involving small armies of fire fighters combined with aircraft that spread fire retardant and saturate fire-fronts with water. Such approaches are extraordinarily costly. Annual spending on fire fighting has been steadily rising. In the US, annual fire-fighting costs now exceed several billion dollars, with individual fire campaigns costing ten to over a hundred million dollars.




Read more:
Spiraling wildfire fighting costs are largely beyond the Forest Service’s control


Although industrial fire-fighting approaches currently enjoy political and social support, the strategy is economically unsustainable. And they are impotent in the face of climate change driven fire disasters such as those currently occurring in California.

A human disaster

Across the fire science community there is growing recognition this “total war” on fire approach has failed. The key to sustainable co-existence with flammable landscapes is instead managing fuels around settlements, and stopping wildfires from starting in the first place.

Spain and Portugal are good examples of why this is so important. In these Mediterranean lands, humans have sustainably co-existed with flammable landscapes for thousands of year. However, the near ubiquitous depopulation of rural lands following the second world war has led to the proliferation of flammable vegetation that had previously been held in check by intensive small-scale subsistence agriculture.

The Village of Rojas in Catalonia, Spain in 1946.
Institut Cartogràfic i Geològic de Catalunya
The same Spanish village in 2017. Large-scale rural depopulation has led to widespread abandonment of formerly agricultural land, massive fuel accumulation and subsequent historically unprecedented fires.
Institut Cartogràfic i Geològic de Catalunya

With the loss of this traditional agriculture Mediterranean countries are now experiencing regular fire disasters (such as the 2018 Greek fires and the 2017 Portuguese and Spanish fires). These are equivalent to fires in more recently settled flammable landscapes in the Americas and Australia.

This seems to be the story in most flammable landscapes on earth: the removal of traditional landscape management by colonisation and globalisation has combined with climate change to turn these landscapes into tinderboxes.

But just as it is unrealistic for Australia to faithfully restore Indigenous fire management practices, expecting a return to historical practices in the Mediterranean is not realistic. There is little economic or social reason for people to return to traditional rural lifestyles, and the gravitational pull of the social and economic advantages in urban areas is too great to stem rural depopulation.

Living with fire

But we can adapt traditional practices to help us live with fire. In the Mediterranean, people are already experimenting with different ways to manage landscapes, such as managing forests for cork and bioenergy, combined with prescribed burning and grazing.

Cork harvesting, selective cutting of trees for bioenergy, understory clearing, and cattle grazing are used in Catalonia, Spain to manage fire hazard by creating a ‘green fire break’.
David Bowman

This can create picturesque landscapes that are fire-resistant and easy to defend. Similarly, in Australia, the Victorian government has created parkland-like green fire breaks that were used for back burning operations to protect communities during 2009 Black Saturday wildfires.

A green fire break in mountain ash forest near Kinglake, Victoria.
David Bowman

The Hobart City Council is planning to use similar fire breaks to protect its outer suburbs with dense bushland. Such management could be used on a larger scale to substantially reduce fire risk. The challenge for landscape fuel management is providing financial and regulatory incentives for citizens and local communities to reduce fuel.

Currently, no society is sustainably co-existing with wildfire. Globally, the situation will worsen under a rapidly-warming climate with ballooning firefighting costs, and huge loss of life and destruction of property. This is the bitter lesson of the Californian fires.The Conversation

David Bowman, Professor, Pyrogeography and Fire Science, University of Tasmania

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Dry winter primes Sydney Basin for early start of bushfire season


Matthias Boer, Western Sydney University; Rachael Helene Nolan, University of Technology Sydney, and Ross Bradstock, University of Wollongong

It might feel like the depths of winter, but Australian fire services are preparing for an early start to the bushfire season. Sydney has been covered with smoke from hazard reduction burns, and the New South Wales Rural Fire Service has forecast a “horrific” season.

Predicting the severity of a bushfire season isn’t easy, and – much like the near-annual announcements of the “worst flu season on record” – repeated warnings can diminish their urgency.

However, new modelling that combines Bureau of Meteorology data with NASA satellite imaging has found that record-setting July warmth and low rainfall have created conditions very similar to 2013, when highly destructive bushfires burned across NSW and Victoria.

Crucially, this research has found we’re approaching a crucial dryness threshold, past which fires are historically far more dangerous.


Read more: Climate change to blame for Australia’s July heat


How to measure bushfire fuel

On September 10, 2013 several bushfires in Sydney’s West caused havoc well before the official start of the bushfire season. These were a precursor to fires that destroyed more than 200 properties a month later. Warm, dry winter weather had dried out the fuels in Sydney’s forests and bush reserves beyond “normal” levels for the time of year.

The timing and severity of those preseason fires were a reminder that the region’s forests are flammable all year round; they can burn whenever the fuel they contain dries out past a certain threshold.

In most forests, there is an abundance of fuel in the form of leaf litter, dead twigs, branches and logs, lower vegetation such as shrubs and grasses, as well as higher foliage and branches.

The flammability of all these different kinds of fuel depends largely on their moisture content. Leaf litter and fine dead branches on the soil surface can dry out in a matter of days, whereas logs may take weeks or months to lose their moisture. The moisture content of shrubs and tree canopies varies depending on the amount of water in the soil, so they reflect the overall rainfall and temperatures across a whole season.

The flammability of an entire forest is therefore a complex calculation of all these different kinds of fuel (both alive and dead) and their different moisture levels.

Mapping Sydney’s forests

In a recent collaborative study, we combined data from a Bureau of Meteorology project that maps water availability levels across Australia with satellite imagery to develop new tools for mapping and monitoring moisture levels of different fuels in forests and woodlands.

We checked these tools by modelling fuel moisture levels during fires in NSW, Victoria and the ACT between 2000 and 2014, and comparing our predictions to historical bushfires.

Our research has identified critical dryness thresholds associated with significant increases in fire area. Rather than a gradual increase in flammability as forests dry out, when dead fuel moisture drops below 15% subsequent bushfires are larger. Another jump occurs when dead fuel moisture levels fall below 10%. We found similar thresholds in growing plants, although their moisture content is measured differently.

These dryness thresholds are pivotal, because they may represent the breakdown of moist natural barriers in landscapes that prevent fires from spreading. Understanding these mechanisms makes it possible to predict fire risk much more accurately.

As part of this project we compared the fuel moisture in Sydney Basin’s forested areas in 2013 and 2017. As shown in the chart below, currently the live fuel moisture level is tracking well below the 2013 values, and is approaching a crucial threshold (indicated by the dotted line).

The moisture content of dead fuel has been more variable, but it has also dipped below the 2013 curve and, if warm dry weather continues, could reach critical levels before the end of August.


The median predicted dead fuel moisture content and live fuel moisture content in forest areas of the Sydney Basin Bioregion in 2013 and 2017. Black dashed horizontal lines indicate fuel moisture threshold values. The start dates of major fires in 2013 are indicated by orange vertical lines.
Author provided, Author provided

In another worrying sign, mapping shows critically dry live fuel is much more abundant in 2017 than it was in 2013.


Remotely sensed live fuel moisture content in forest areas of the Sydney Basin Bioregion in July 2013 (left) and July 2017 (right). Click to enlarge.
Author provided

It’s clear that much of the Sydney Basin is dangerously primed for major bushfires, at least until it receives major rainfall. Forecasts for windy but largely dry weather in coming weeks may exacerbate this problem.

These new insights into landscape-scale fuel dryness provide a powerful indicator of what might be expected. They also build our capacity for week by week monitoring of fire potential.

The ConversationPreparation by both fire management authorities and exposed homeowners is now an immediate priority, to cope with the strong likelihood of an early and severe fire season.

Matthias Boer, Associate Professor, Hawkesbury Institute for the Environment, Western Sydney University; Rachael Helene Nolan, Postdoctoral research fellow, University of Technology Sydney, and Ross Bradstock, Professor, Centre for Environmental Risk Management of Bushfires, University of Wollongong

This article was originally published on The Conversation. Read the original article.

Where to take refuge in your home during a bushfire



File 20170817 28092 1s4jus6
Fire threatening a house in Pelican Bay in 2006. If you need to shelter from a fire in your house, know where your exits are and be aware of surrounding vegetation.
thinboyfatter/Flickr, CC BY-SA

Douglas Brown, University of Sydney

When you live in a bushfire-prone area you can’t ignore the danger. Most individuals and families address this necessity by preparing a bushfire survival plan. The best way to survive a bushfire is not to be there when it arrives.

For most Australian fire agencies the “leave early” policy has largely replaced the previous “stay and defend or leave early” one. This
reflects an emphasis on preserving human life during a bushfire event – an emphasis that has strengthened since the 2009 Black Saturday bushfires.


Read more: How to prepare your home for a bushfire – and when to leave


Even when planning to leave early, unexpected events can occur. Not being able to find a child or family pet may delay departure until it’s no longer safe to travel. Taking refuge in your home then becomes a last resort, a worst-case scenario. But this contingency is worth considering as part of your bushfire survival plan.

If you do need to take refuge inside your home during a bushfire, which parts are likely to be the safest? As part of my PhD research, I asked 252 residents living in bushfire-prone areas which parts of their houses they would shelter in during a bushfire, which parts they would avoid, and why. I then analysed the features of these locations against the known places where people died in their home during bushfires in Australia from 1901 to 2011.

Determining the safer places to shelter is further complicated as all houses are not the same. There are many different types, with large variations in design, construction materials, location and surrounding vegetation. It is therefore not possible to give absolute answers on where people should take shelter in their homes during a bushfire, but some general guidelines can be given.

Where are the safer spaces to shelter?

Upstairs is generally a more dangerous space to seek shelter during a bushfire. Upstairs levels are more difficult to escape from. Often they have large windows and sliding glass doors which are designed to capture views, but due to radiant heat and strong winds can crack and implode. Upper levels are often constructed of lightweight materials that are more flammable and vulnerable to direct flame contact from burning trees.

The ground floor is generally a safer space to shelter. The ground level usually has more external doors from which the occupant can escape. On a sloping block, however, the easiest level from which to exit may be the first floor. The ground level often has smaller windows (except those leading to entertainment areas). From the ground floor it is easier to get to the driveway and closer to an external water source such as a water tank.

People often suggest the bathroom as a good place to shelter during a bushfire. However, the bathroom can also be dangerous. During a bushfire, mains water is often cut or the pressure is reduced to a trickle. Despite having tiled walls, non-combustible fittings and a water supply, bathrooms like other rooms are vulnerable to the collapse of a burning ceiling when embers have ignited in the roof cavity.

Most bathrooms do not have an external door that residents can use to exit the house. In a bathroom it can be difficult to see the progress of a fire. And as bathrooms are small enclosed spaces they may be more vulnerable to carbon monoxide poisoning.


Read more: Low flammability plants could help our homes survive bushfires


My advice is to look at all the external ground floor doors (while remembering that glass doors can be dangerous because of their vulnerability to radiant heat), and determine which of them provide access to adjoining outside paved, gravel, concrete or other non-combustible areas. You should also see if there is a small window from which you can observe the progress of the bushfire, and if there is a sink close by to store water. Where possible consider installing a fire alarm that has a carbon monoxide sensor with audible and visual alerts.

When you have identified the most suitable place in the house to actively shelter during a bushfire, follow the bushfire preparation activities provided by fire authorities. Some of these will include looking out of a window to follow the progress of the fire and being aware of current bushfire updates on the radio and via mobile phone. There is no such thing as passive sheltering.

Being inside your home as the fire passes offers more protection than being outside. But it should be seen as a last resort, with leaving early the preferred action. Fire agencies work hard to inform residents of days when bushfires are likely, and to provide updates on fires that do break out. Residents in bushfire-prone areas should take these warnings and updates seriously and leave their properties when advised to do so, especially when catastrophic fires are expected.

The ConversationThe advice given in this article is general and may not suit every circumstance.

Douglas Brown, PhD candidate (approved), University of Sydney

This article was originally published on The Conversation. Read the original article.