The Hidden Killer

Asbestos

Learning Outcomes

1. Demonstrate understanding of the dangers associated with asbestos

2. Recall the 3 different sources of asbestos

3. Identify where asbestos can be found in day to day use

Asbestos – a brief overview

The Hidden Killer!

First task – 5 minutes

• On the piece of paper in front of you, I want you to think of the following questions and write your response – for all to see:

1. What does asbestos mean to you?2. Can you state an example of

asbestos that you have seen?

What is Asbestos?

• Asbestos is a term given to a number of naturally occurring mineral fibres which have been exploited commercially for their useful properties.

• Asbestos is mined throughout the world - South Africa, Australia, Canada

• 3 most common types:– Amosite (brown)– Crocidolite (blue)– Chrysotile (white)

Asbestos Fibres

Chrysotile fibre bundle (image 600 x magnification) exposed on the surface of a weathered cement sheet.

Individual amosite fibres

Amosite fibre bundle (image 2000 x magnification)

Asbestos Useful Properties

• High tensile strength• Chemical resistance• Good thermal insulation• Incombustible• Flexible - can be woven• Can be mixed with cement and

plastic and retain its properties

History of Asbestos Use in UK

• First imported ~1880s• Main period of use 1950 – 1980• 1973 - Voluntary industry ban on

spraying of asbestos• 1985 – Supply of amosite and

crocidolite prohibited• 1999 - Use of all forms of chrysotile

prohibited

Advert from New Scientist

June 1957

Application of sprayed asbestos coating c1950-

1960

Asbestos Related Disease

• Pleural Plaques• Asbestosis

– Fibrosis/scarring of lung– Dose related (mod-high) and progressive

• Lung Cancer• Mesothelioma

– Specific cancer of inner lining of chest wall or abdominal cavity

– Nearly always fatal

Onset can range from 10 – 60 years after first exposure to asbestos.

What this means in ‘real terms’

• YouTube - Ian Wright's Asbestos Warning

Group activity – 5 minutes

• In groups, discuss the video and facts on the use of asbestos.

• What have you learnt that has highlighted the dangers of asbestos?

• Note your findings down on the flipchart paper and choose a person to feedback

Asbestos Exposure - Past and Present

• Manufacture of asbestos products.• Installation of asbestos products.

• Removal of asbestos containing materials (ACMs) without suitable controls.

• Inadvertent disturbance of ACMs during maintenance activities.

Past Exposure

Present Exposure

Release of Fibres from ACMs: Friability

• Loose-fill lagging

• Lagging

• Sprayed insulation

• Asbestos insulation board

• Asbestos cement

• Floor tiles

MOST FRIABLE

LEAST FRIABLE

Good Control v Poor Control

Typical Exposure LevelsTechnique

Typical Exposure

f/mlComments

Controlled wet stripping of lagging and sprayed coating

Up to 1Thorough soaking of the lagging with a wetting agent followed by careful removal

Uncontrolled dry stripping of lagging 1-100 Stripping dry or where dry

patches are encountered

Careful removal of whole AIB boards Up to 3

Unscrewing (with shadow vacuuming with the spray application of a wetting agent on unsealed surfaces)

Breaking and ripping out AIB 5-20 Carried out dry with no

unscrewing

HSE Control Limit 0.1 Averaged over a period of 4 hours.

Real life account

• The Hidden Killer - Christopher Morgan's Story

Group activity – 5 minutes

• I’m sure you will agree that what you have just seen was a very ‘moving’ video, with some very clear messages.

• Discuss what important message you will take away with you today?

• Nominate a person in your group to feed back.

Asbestos insulating board used as a

ceiling board for fire resistance, plumber

wasn’t informed/aware

when he fixed the leak

Loose infill under floorboards exposed during central heating installation – Refurbishment survey not completed

Non licensable ACMs

• Asbestos cement• Textured coatings• Composite materials

Asbestos Essentials for Non Licensed Tasks

Licensable ACMs

• Asbestos Insulating Board• Sprayed coatings• Lagging

Individual Task

• Complete the task sheet –‘The hunt for asbestos’

• Consider the areas listed and the ‘bubbles’ on the house picture – where are ACM’s situated?

• Good luck!

Learning Outcomes

1. Demonstrate understanding of the dangers associated with asbestos

2. Recall the 3 different types of asbestos

3. Identify where asbestos can be found in day to day use