There are upwards of 3,000 wildfires in New Zealand each year and many thousands more worldwide. While most people’s primary concern is the fires themselves, there’s something of equal concern to consider, and that’s asbestos.

In Aotearoa New Zealand, structure loss in wildfires is often kept to a minimum, so asbestos exposure risks are not generally high. However, with the risk not being zero and exposure risks being much higher overseas, it’s worth being aware of the dangers asbestos in wildfires poses and what we should be doing about the situation. After all, knowledge is power.

 

What Happens to Asbestos in a Fire?

Asbestos was once highly-regarded and widely used for its fire-resistant properties. However, when it’s exposed to high temperatures, it’s not thermally stable.

White asbestos (chrysotile) decomposes at temperatures as low as 850°C, while blue asbestos (crocidolite) and brown asbestos (amosite) decompose at around 1,000°C.

After prolonged exposure to those temperatures, the asbestos will be converted to dust, which is when it’s in its most deadly form. And that’s not even the worst part.

Asbestos cement sheeting can not only disintegrate in a fire, but it can explode. Once exploded, the tiny particles can be released into the air, spreading far and wide and putting people at risk of exposure and future health conditions.

 

How Can You Be Exposed to Asbestos After a Wildfire?

There are at least three exposure sources to be aware of after a wildfire or even a standard structure fire from another cause. These can include:

 

• Direct inhalation of asbestos in the fire if you were there when it broke out

• Inhalation of asbestos fibres in the air from the structure, driven by the wind or mechanics after the fire has been put out

• Eating affected produce

 

The severity of the exposure event can depend on how much ACM there was in the property and in the air. However, the risk may be significantly reduced if asbestos removal and demolition companies remove affected materials as quickly as possible after a fire.

What Are the Health Effects of Asbestos in a Fire?

The health effects associated with asbestos burned in a wildfire or regular structure fire haven’t been widely studied. However, smoke inhalation and thermal injury are the most likely adverse health effects immediately after a fire. The ACM may also irritate your respiratory tract, skin, and eyes.

There is no direct evidence associated with any long-term health risks involving asbestos and fires, but that’s not to say there are none. There simply hasn’t been enough research done to draw accurate conclusions.

However, whether you’re exposed to asbestos after a natural disaster or a house renovation, you may be at risk of asbestos-related conditions in the future, such as asbestosis and mesothelioma.

 

Can the Risks Associated With Asbestos in Fires Be Mitigated?

According to the Ministry of Health, there are mitigating factors that may limit just how exposed the general public is to asbestos in the event of a standalone fire or wildfire event. These factors can include:

 

• Not all asbestos-containing materials being burned in the fire (e.g., the fire is extinguished before it affects the majority of the asbestos cladding)

• Asbestos fibres being trapped in large pieces of material

• Asbestos cement sheeting being deposited as large pieces in a fire

• Respirable fibres only being a small fraction of the total amount of asbestos released

• Fibres being denatured after exposure to high temperatures for prolonged periods

• Short exposure duration

• Atmospheric dispersion (e.g., rain reducing asbestos fibre concentrations)

 

How to Keep Yourself Safe From Asbestos After a Wildfire

Even though most Kiwis haven’t had first-hand experience with a wildfire affecting our homes, that doesn’t mean we never will. The more you know about asbestos in fires, the easier you may find it to keep calm and protect yourself.

Most importantly, wear a mask when you’re in an area where a wildfire has affected an asbestos-containing structure. Wash all your clothing in a wildfire-affected area to reduce secondhand exposure, and refrain from sweeping up any unknown building materials that may contain asbestos.

If you are involved in any cleanup efforts around your property, always wet down materials to prevent any fibres from becoming airborne. An enclosed negative pressure vacuum cleaner with a HEPA filter may assist with this.

It’s also essential to avoid skin contact as much as possible. When outside in wildfire-affected areas, wear masks, long-sleeved shirts and pants, and covered-in shoes. Single-use coveralls may also be a wise investment for peace of mind.

Understandably, your focus may not be on asbestos as you’re dealing with the after-effects of a fire that potentially affects your entire way of life. However, by considering that it’s possibly present and acting accordingly, you may lower your risks of associated illnesses in later life.