Don’t be fooled by the expert reassurances that only friable, or dusty, asbestos is dangerous. It’s true that dust is the danger: inhaling the microscopic particles of asbestos dust can decades later result in the deadly cancers caused by asbestos, and no safe level of exposure has yet to be identified.

Non-friable or bonded asbestos, we are told, is safe. That’s true, assuming the glue still bonds the fibres and it remains undisturbed. But asbestos cement manufacturing in Australia ceased in the mid-1980s. That means the asbestos fibre cement in our buildings is now between 40 and 100 years old, and its bonding agent no longer glues the fibres together effectively. Tests around the world have demonstrated that such old asbestos cement is now past its used-by date. The bonding is no longer effective, and when the fibro is exposed to the wind and rain, it sheds fibres that scatter through the surrounding environment.

So the next time you walk past a decaying corrugated roof or fence, hold your breath!