Asbestos

Asbestos Definition and Identification

What is asbestos?
Asbestos is the name used for a Hazardous Substance covering a group of six naturally occurring fibrous minerals: chrysotile, crocidolite, amosite, anthophyllite, tremolite, and actinolite. Among these, chrysotile has been the most commonly used type of asbestos.

Hazards and risks
Asbestos fibres are microscopic and if inhaled, become lodged in the lungs. Prolonged exposure and inhalation of the fibres can cause serious and fatal illnesses including

asbestosis (scarring of lung tissue)
mesothelioma (malignant tumours, cancers which develop around the lungs or intestine)
pleural plaques (thickening of membranes around the lungs)
lung cancer.

Asbestos-containing material or ACM means any material or thing that, as part of its design, contains asbestos fibres. Asbestos fibres are extremely durable, resistant to fire and most chemicals. For this reason asbestos was in the past used in the manufacture of a wide variety of commercial and domestic construction products from the 1940’s through to the 1990’s:

Roofing tars, felts, siding, and shingles
Cladding e.g. Siding shingles
Vinyl floor tiles, sheeting, adhesives
Ceiling materials e.g. Acoustic ceilings, textured and popcorn ceilings
Cement compounds
Textile products
Houses built between 1930 and 1950 may have asbestos as insulation
Insulation board for thermal protection such as millboard, or cement sheets (e.g. Around fireplaces)
Artificial ashes and embers sold for use in old gas-fired fireplaces may contain asbestos.
Backing material for floor tiles and vinyl sheets
Textured wall surfaces
Insulation lagging around pipes, heaters and hot water cylinders
Spouting for drainage and water supplies
Drywall and joint compound and plaster
“Transite” panels, siding, countertops, and pipes
Stage curtains
Interior fire doors
HVAC flexible duct connectors

Managing Risks

Identifying the presence of Asbestos
The Health and Safety Work (Asbestos) Regulations 2016 require that the person carrying out or managing the work, identify if there is any asbestos present before beginning work.
Identification of asbestos presence can only be carried out by an IANZ accredited Laboratory. The building will need to be inspected by a competent person who is licensed to carry out this work.

Approved Laboratory Register (WORKSAFE)
Asbestos Removal/Assessor License (WORKSAFE)
Conducting Asbestos Surveys (WORKSAFE)
Licence Holder Register (WORKSAFE)
Standards and Testing (WORKSAFE)

Mitigating risk of materials left in place
If the external cladding/roofing containing asbestos is undamaged, the presence of asbestos should not cause any concern. Even if the cladding is deteriorating, the cladding should be sealed rather than removed or replaced, as the later poses greater health risks through the disturbance and release of high-risk concentrations of fibres into the air. If left in place, the amount of fibres released is not considered to be a health risk. Seal the surface with an approved commercial sealant or coating to stop fibre release. Check with the manufacturer that the coating will not increase fire risks. Surface preparation: do not water blast as this will result in a high level of fibre release which will become a hazard when dry.

Caution: Where the roofing material containing asbestos, especially weathered or brittle roofing, the ceiling space under the roof may have high levels of asbestos dust.

More information:

Asbestos beware – managing asbestos
Demolition and refurbishment (WORKSAFE)

Risk management plans
Where there is the possibility, due to the age of the building, that there may be asbestos present in some of the building products, the person in charge needs to determine if or where asbestos exists and how associated risks will be managed in the future if there is any alterations, additions, refurbishment or demolition work carried out:

Asbestos Management Plan (WORKSAFE)

Before any refurbishment or demolition work on the building begins, have refurbishment and demolition plan. If demolition work, identify and remove all asbestos products that could be disturbed by the demolition work. Exemptions to removing asbestos before demolition include:

If the asbestos can only be reached by demolishing part of the building.
If there is an emergency. For emergency procedures (workplace or home) see WorkSafe NZ guidance.

Removal of asbestos-containing materials
From 4 April 2016, only a licensed asbestos removalist has the legal authority to remove asbestos if

more than 10 m2 of non-friable asbestos has to be removed over the whole course of the project for the site
friable asbestos removal work (where fibre release is likely to be high).

A licensed asbestos removalist can be a person holding a current Certificate of Competence until April 2018, after which they must hold an approved licence as an Asbestos removal License or Asbestos assessor licence. Once the asbestos is removed an independent licensed asbestos assessor must carry out a clearance inspection and provide a signed clearance certificate.