Asbestos

Awareness

Updated February 2014

What is Asbestos

• Asbestos is the name applied to six naturally occurring minerals that are mined from the earth.

• Amosite• Chrysotile• Tremolite• Actinolite• Anthrophyllite• Crocidolite

What is Asbestos

• Three are used more commonly:

• Chrysotile - white asbestos

– asbestos cloth and cement products

• Amosite - brown asbestos

– heat insulation and pipe lagging

• Crocidolite - blue asbestos

– very high temperature and acid resistant purposes

Asbestos Products

• Non Friable• the asbestos fibres are bonded by another

material

• Friable• non bonded asbestos fabric or material• is in powder form• can be reduced to powder by hand pressure

Asbestos Products• Asbestos was generally processed as:

• Fibrous

• sprayed

• preformed

• Textile

• woven

• wound

• Mixed with a binder

Asbestos Materials

• Friable products

• sprayed fire retardant

• thermal lagging

• fire blankets

• welding blankets

• backing to sheet vinyl floor covering

• flexible connection

Asbestos Materials

• Non Friable• cement products

– flat sheet

– corrugated sheet

– pipes

– compressed sheet

• vinyl floor tiles

• switch board

• brake and clutch lining

When is Asbestos a hazard

• When asbestos fibres become airborne

• friable

- disturbance of loose or non bonded asbestos

• non friable- when the cement or resin breaks down

When is Asbestos a hazard

• Respirable Fibre

• less than 3 microns in diameter

• longer than 5 microns

• with a length to diameter ratio greater than 3:1

Health effects

• The body cannot breakdown asbestos fibres.

• Three primary diseases associated with asbestos exposure

• Mesothelioma

• Lung Cancer

• Asbestosis

Asbestos and your health• The potential for harm depends on:

• fibre size and type

• length of exposure

• concentration of Respirable fibres

• individual susceptibility

• influence of other factors

Identification of Asbestos

• Materials containing asbestos are not readily identified.

• Laboratory analysis

- X-ray diffraction

- Polarising light microscopy in conjunction with dispersion staining

- Electron microscope

Limit asbestos exposure

• Installed asbestos• be aware of any installed asbestos

• asbestos register

• asbestos management plan

• Do not disturb asbestos• no drilling, cutting, sawing, sanding

• no activities that creates dust

Limit asbestos exposure• Housekeeping

• Check asbestos register before commencing any minor work

• ensure that damaged material is repaired by competent people

• replace broken or damaged ceiling tiles

• Policy and Procedure• asbestos management procedure

• for accessing ceiling space

• areas where asbestos is present- air monitoring, after hours work

Management of Asbestos

• DECD Procedure• Asbestos Management Procedure

• Regulations and Codes of Practice• Work Health and Safety Regulations 2012 – Chapter 8 - Asbestos• Code of Practice for the Management and Control of Asbestos

Airborne asbestos fibres• Membrane filter method

• Sample is collected by:

- drawing a measured quantity of air through a membrane filter by means of a pump

- filter is transformed to a transparent, optically homogenous specimen

- the fibres are then sized and counted using a microscope and eyed graticule

- the results are expressed as fibres per millilitre of air, calculated from the number of fibres and the measured volume of air sampled.

Asbestos Pictures…..

Shows 2 plugs with “Warning” labels stuck over them.

Same plugs with one label and PVC cap removed to expose asbestos “plug”.

A single plug with the cap missing – white asbestos.Plug has fallen down making it more visible.Lower right shows plastic former still in place from construction. (These formers were supposed to have been removed during construction).

Two labeled caps with white asbestos visible in the underside of the slab just right of a paper label.

Plugs that have been tampered with and resealed. Note a third type of warning label.

Another example of white asbestos contamination in the underside of the concrete slab below the yellow sticker.

Under side of slab contamination. This example shows 2 separate spots of white asbestos contamination. Each is above the white sticker.Note the white patch left of EC1059 sticker IS NOT asbestos.

This is a view looking down on top of a slab. The damaged carpet has been peeled back to show the inside of the PVC sleeve with white asbestos visible around the top of the hole. Cables had been pushed up through this hole to feed a floor fastened power or telephone socket.

This is unusual contamination on the under side of a slab, approximately 50mm across.A worker has thrown wet white asbestos up during construction and it has remained stuck to the slab.

Shows loose grey/brown asbestos (Amosite) on top of ceiling tiles under a large water pipe.

Shows a similar wall penetration with NON ASBESTOS fire proof packing. It is very difficult to distinguish between asbestos and asbestos free fibrous material. All plumbing waste floor penetrations so far have been packed with asbestos free fibrous insulation.

Shows white asbestos rich mastic sealant on an air conditioning duct flange after the joint had been opened. This is a well bonded form of white asbestos that cannot easily be compromised without high temperatures, some solvents or years of exposure to sunlight.

There are many uses of asbestos to be found within and around our environment, mostly commonly in the form of asbestos cement products. It can be found as:

• flat or corrugated sheets used mainly for garages and sheds• cold water storage tanks• external rainwater pipes and guttering• fascia boards• as a lining cladding for fire protection• for internal partition walls

Asbestos cement is a hard, brittle, greyish material, however if there are any suspicions that a product is asbestos it should be treated as such.

In DECD worksites, products known to contain asbestos must be marked with appropriate safety signage. Refer to the worksite’s Asbestos Register and Asbestos Management Plan and to the DECD Asbestos Management Procedure

                                       

Some examples of Asbestos Signs

Asbestos may be present in many geological samples in varying different forms

Refer to Hazard Alert 21 Asbestos in Rock Sample Kits

While asbestos roofs are not common in DECS worksites, they can be found in some older worksites, and SA homes.

There are at least three types of asbestos shingles. Regular flat shingle tiles are shown at top, common diamond shaped tiles are shown at middle, and side-lap tiles are shown below. It is difficult to find asbestos replacement tiles that match the original roof in colour shade. Note the three replacement tiles on the diamond asbestos roof (they appear whiter than the original tiles).

Asbestos is a brittle and fragile material. It cannot be walked on as the tiles will crack and these hairline cracks, which are hard to see, will leak. Fragile roof considerations need to be made as well. Signage is appropriate.

Asbestos sheets on a roof. These sheets are also known as “Deep 6”. This type of roof is fragile when walked upon, and appropriate signage is required. Painting the roof can minimize hazards associated with flaking fibres.

Twisted yarn with asbestos fibre. Extensively used as caulking, sealing and heat insulating materials on thermal installations and heat conducting systems, eg kilns (above), slow combustion fire doors, incubators, mantles and laboratory ovens (left).

Asbestos fencing can still be found. This is also known as “Deep 6”. Similar sheets were also used in roofing. Note its friable nature when broken or chipped. This can be a hazard when removing the fence, or if it is rubbed against.

“Deep 6” asbestos fencing with warning signs.

Another example of an asbestos “deep 6” style of fencing. Removal of such fences should be in accordance with the DECD Asbestos Management Procedure.

Carrels, common in the later half of the ’70’s and in the 1980-’s, can still be found in some schools. They are often located in “time out” rooms, resource centres, and language rooms. The surfaces are often defaced, due to the secluded nature of the space. Asbestos was often used as a base, underneath the soft plastic/leather surface.

Backing to sheet vinyl floor covering can be made from asbestos, as pictured above. Vinyl floor tiles can contain asbestos in the tile mix, which deteriorates over time, and can release asbestos fibers. Such flooring should be replaced, or covered, if deemed a hazard.

Asbestos thermal lagging around pipe work

Asbestos cement flue pipes

Another example of asbestos products found in worksites.

Asbestos thread can be found on gas mantles, used in camping lights. Radioactive Thorium is also present in the mantle material. (Thorium when heated by LPG flame, emits radiation that is weighted less heavily in the infrared and more heavily in the visible spectrum, leading to an enhanced output of useful light ). Wash hands after handling.

Asbestos – white substance in the ground in this picture

Crushed asbestos and mud

Asbestos