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Electrical contactor frames with asbestos

Description

Industrial contactors (often used for switching motor starters) produced by Siemens Germany, prior to 1993. The frame structure is a grey coloured thermoset plastic (Bakelite-type) material containing chrysotile asbestos.

Certain contactors produced up to 1982 contained asbestos in thermoset plastic parts. No asbestos is said to have been used in production since 1985 (Siemens Germany).

The affected units included frame sizes:

  • 3TA
  • 3TB (first generation)
    • 3TB52
    • 3TB53
    • 3TB54
    • 3TB55
    • 3TB56
    • 3TB57
    • 3TB58
  • 3TC (first generation)

The Frames within 3TB40-43 to 3TB51 range is said not to contain asbestos. Although, a 3TB50 in Australia was sampled and tested and found to contain chrysotile asbestos.

Brands/products

  • Siemens

Years of production/use

Prior to 1993

These frame designs are still in use with a current spare component market available which means the older frame can be updated with replaceable components.  There are many older frames across the 3TA/B/C range available for sale in online market sites.

The use of asbestos was banned in Germany in 1993. The manufacture date can be identified buy a G followed by a 6-digit combination of numbers (G mark) on the frame, the first two indicating the year of manufacture. G marks are not always present across all models. For safe assessment, units produced prior to 1993 should be regarded as a risk for asbestos content until proven otherwise.

Residential uses

  • N/a

Industrial uses
  • Large, fixed plant/infrastructure applications requiring continuous high voltage applications.
  • Maritime vessels/platforms
  • Railway and transport
  • Power stations
Be aware

The housing may suffer slight damage, particularly in high voltage industrial use, when the units trip under heavy voltage load, causing material debris.  This may be a result of age and repeated use.

Asbestos cement cable troughing

Description

Also known as cable trays.

Moulded AC housing used to cover and protect high voltage cabling between connecting junctions from weather and unintended direct contact.

Usually constructed in section lengths with a detachable lid for maintenance access.

Can be grounded, fixed on supports or suspended.

Brands/products

  • Fibrolite

Years of production/use

Late 1920s to early 1980s.

Residential uses

  • Not known

Industrial uses
  • Electrical sub-stations
  • Formerly used as railway cable troughing adjacent to tracks housing electrical, communication and signalling cables – gradually being replaced
Be aware

Damaged and weathered troughing may be weakened and in a friable state.

Dust and debris in vicinity of installation.

Brake pads in transformer tap changer motor units

Description

A tap changer is a mechanism in grid transformers which allows for variable turn ratios to be selected in steps. Access points, known as taps, are connected along either the primary or secondary winding, to create the correct voltage output.

This provides the ability to control the input voltage rating of the transformer at the point of power consumption and makes it easier to regulate the voltage output when, for example: there are consumption surges within a grid.

These mechanical systems incorporate a braking system for the drive motor. Brake pads/shoes are used, which provides a risk for asbestos in older friction materials previously installed in older braking systems.

Brands/products

  • No brand identified

Years of production/use

Prior to 1990

Residential uses

  • n/a

Industrial uses
  • Power stations and sub-stations
  • Wherever older significant power infrastructure is installed
Be aware

Residue and dust in immediate vicinity, particularly in enclosed units, is likely to contain respirable asbestos fibres.

Brake shoes in this application do not receive continual use – useable life expectancy can be extended for decades if in lesser used break assemblies, which provides a risk of ACM in friction materials installed prior to 2003. Images were taken in 2018-19 of units installed in 1980s.

Woven asbestos seals in fuse switch boxes

Description

Flexible woven (rope) asbestos seal fitted to interior of box housing or into flange inside door edging.  

Woven seal may vary in colour from white to grey to brown depending on age and environmental exposure.

Brands/products
  • Wilco
  • Ottomill
  • Federal
  • Kelvin
Years of production/use

Prior to 1990

Residential uses

N/A

Industrial uses

Industrial structures, electrical substations and installations, railway signal boxes

Be aware

Woven seal may become hard and brittle with age. Abrasion with other surfaces in contact may result in ACM debris in box.

Woven asbestos insulates in electrical components

Description

Asbestos woven cloth and rope used as insulation in electrical components to prevent fire during short circuit. Also known as flash pads.

Woven cloth is usually made from chrysotile asbestos and the material can be up to 95% asbestos.

May have been installed initially or through life of equipment maintenance.

See Woven asbestos textile for insulation for other uses of same product.

Brands/products

N/A

Years of production/use

Prior to 1990

Residential uses
  • Circuit breakers, fuse holders in meter boxes
  • Switchboxes, choke boxes, relay boxes, contactor boxes
Industrial uses
  • Electrical switch rooms, plant power units, lift motors. Plant electrical infrastructure
Be aware

Due to the likely high raw fibre content – these materials may be classified as friable in certain workplaces.

Any disturbance of older woven asbestos cloth may release fibres to become airborne.

Asbestos cement conduit for electrical and telecommunication cables

Description

AC piping used as conduit for electricity supply, local government authorities and telecommunications (PMG/Telecom Australia).

Used to convey high voltage and low voltage cables into and out of substations and telephone line exchanges under road crossings, alongside roads or under footpaths. Some were buried empty for future use. 

Manufactured with Portland cement, asbestos and silica and then autoclaved. Designed for underground and through building installation.

Hardie’s also manufactured conduit with K-Lite material, which was composed of 10-15% amosite asbestos and 85-90% hydrous calcium silicate.

Usually in 13’ (3.96m) straight lengths. Some conduit may be ribbed, other with smooth surfaces.

Bends of four different lengths to 16°, 22.5°, 45° and 90° were also produced, as well as a range of diameters: 2”, 3”, 4” and 5.5”.

Brands/products
  • Fibrolite
  • Tasbestos
Years of production/use

1920s – late 1970s

Telstra guidance (2015) advises ACM conduit for telecommunications cabling was used between late 1950s to the latter 1970s. 

Residential uses
  • Multi-storey apartments
  • May be suspended in void spaces or within enclosed parking areas
Industrial uses
  • Any industrial site
  • Commercial office buildings
  • Mains infrastructure underground
  • Telephone exchanges, electrical substations, telecommunications and electrical underground pits and tunnels
Be aware

Conduit may be mistaken for AC water pipes. Beware of electricity.

After 30+ years material becomes hard and brittle.

Laying incorporated the use of bituminous cement compound within the spigot joint.

Asbestos cement sheeting and low density board as electrical insulation

Description

AC sheeting or LDB cut and shaped for confined/enclosed spaces as insulation material/fire protection from electrical arcing or combustion.

May be professionally installed or by homeowner.

Years of production/use

Prior to 2003. Amateur installations possibly after this time.

Brands/products
  • Fibrolite
  • Durabestos
  • Villaboard
  • Millboard
  • Asbestolux (LDB)
  • Bevelux (LDB)
  • Duralux (LDB )(Wunderlich Qld)

    • Duralux is also a current brand name for a fibre board product manufactured in Australia with no asbestos

Residential uses
  • Meter and fuse boxes
  • Electrical switchgear housings in multi-storey apartments
Industrial uses
  • Switch rooms, switchgear cabinets, electrical partitions, control rooms for electrically powered systems
Be aware

Sheets cut on site will have exposed edges, damage to these edges over time may introduce asbestos containing dust/debris into space.

Drilling to install new equipment will expose fibres that will likely become airborne.

Arc shields and chute covers

Description

Shields and covers to prevent electrical arc flashes occurring between conductive points on equipment.

Often high density AC.

May have been manufactured by electrical components factory.

Refer K-Lite information page.

Years of production/use

Early 20th Century up to 1990

Brands/products
  • General Electric
  • Fibrolite
  • K-Lite
  • Other internationally recognised brands
Residential uses

Older unit complexes

Industrial uses

More likely on older electrical control panels for elevators, factories, and other infrastructure where fixed plant is located

Be aware

May be housed in a custom made cabinet made from, or lined with, asbestos millboard or AC sheeting.

The presence of these may also indicate the likelihood of other ACM such as woven insulating materials in circuit breakers, wire insulation or cable wraps.

Electrical fuse/meter board backing

Description

Older electrical switchboard mounting panels and meter panels manufactured from an asbestos/resin or asbestos/coal tar pitch composite.

The panels are usually a dark brown or black colour, have a rough fibrous or wood like surface finish and may have a strong tar smell.

Hardie’s marketed a product named Dilex from 1933 as ebonised asbestos insulating board. In the 1950s New Dilex was introduced and advertised as unpolished, matte or polished.

Some may also be lined with AC sheeting.

Brand names may appear on rear of panel.

Brands/products
  • Lebah
  • Zelemite
  • Miscolite
  • Ausbestos
  • New Dilex
  • Dilex
Years of production/use

Most installed prior to 1990

Residential uses
  • Meter boxes
Industrial uses
  • Switch boards, electrical partition panels
  • Mains electrical grid infrastructure
Be aware

Drilling, cutting, sanding or water blasting these panels may release asbestos fibres.

Meter boxes fitted with such panels may contain friable asbestos dust/debris inside.

The inside of front covers of older electro-mechanical Watthour meters may have been sealed with asbestos sealants/compounds.

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