Asbestos

Question 1

What Is Asbestos?

Answer 1

Asbestos is a term for a group of naturally occurring silicate minerals that are widely
distributed in rocks and deposits

Question 2

Phase-Out of Asbestos

Answer 2

Late 1970s – Friable sprayed asbestos insulation / lagging was phased out of use.
1982 – Asbestos fibre cement sheeting was phased out of use.
1984 – Asbestos corrugated cement sheeting was phased out of use.
1986 – All other asbestos cement products were phased out of use.
1997 – Asbestos gaskets were phased out of use.
December 2003 – The use of asbestos was banned in Australia

Question 3

From what year can we expect houses to not have asbestos?

Answer 3

Buildings built after 1990 are considered unlikely to have significant amounts of asbestos
containing materials (ACM) in-situ

Question 4

What is friability

Answer 4

“Friability” describes the ability of a solid substance to be reduced to smaller pieces with
little effort, such as through rubbing or applying pressure

Question 5

What is Non-Friable

Answer 5

Usually hold the asbestos fibres within the matrix of a
bonding material and make it difficult to be crumbled or pulverised without a substantially
greater force applied than hand pressure

Question 6

Inhaling Asbestos

Answer 6

Respirable asbestos fibres that are inhaled are deposited into the small air sacs, or alveoli, within the lungs. Once deposited, these fibres are not easily removed

Question 7

2 Theories of how it causes disease

Answer 7

‘Threshold Theory’
− Disease occurs only after the body’s defences are overwhelmed after receiving
high doses over long periods.

‘One Fibre Theory’
− Disease occurs after exposure to 1 asbestos fibre

Question 8

Likelihood of disease

Answer 8

‘3 Ds’:
Dose (intensity) – the quantity of dust inhaled over time.
Dimension of fibres - respirable fibres are less than 3 µm in diameter.
Durability – the bio-persistence of fibres in the lungs (i.e. the ability to resist
dissolution and mechanical break-down)