This resource is provided to help Australian businesses and individuals understand the issues surrounding commercial and domestic asbestos removal.

RELATED ISSUES:

Introduction

An estimated 1.3 million employees are exposed to asbestos in construction and general industry; the heaviest exposures are from the removal of asbestos during renovation and demolition. Exposure to asbestos can cause asbestosis; mesothelioma; lung cancer and cancers of the oesophagus, stomach, colon and rectum.

Under current legislation (Safety, Health and Welfare at Work (Construction) Regulations 2006) there is a duty on employers to identify any Asbestos Containing Material (ACM) before commencing demolition, building maintenance or removal works, if there is any doubt that asbestos is present then the employer must follow the current legislative steps to identify the presence of asbestos.

Asbestos Air Monitoring

According to Safe Work Australia, Guidance Note on the Membrane Filter Method for estimating Airborne Asbestos Fibres, 2nd Edition [NOHSC: 3003(2005)] "Air Monitoring means airborne asbestos fibre sampling to assist in assessing exposures and the effectiveness of control measures".

As per Safe Work Australia Code of Practice for the Safe Removal of Asbestos, 2nd Edition [NOHSC: 2002(2005)], section 9.8 Air Monitoring states:

'Air Monitoring should be performed whenever ACM are being removed, to ensure the control measures are effective'.

All Asbestos air monitoring must be carried out in accordance with the Guidance Note on the Membrane Filter Method for Estimating Airborne Asbestos Fibres [NOHSC: 3003(2005)].

Who carries out Asbestos Air Monitoring?

A competent and qualified person who is independent of the removalist company is required to carry out the air monitoring. The person must be able to determine the location, rate, and frequency of sampling, able to implement suitable sampling strategies where necessary, whether an air monitoring program is required and whether additional air sampling is required.

Nominating the person who carries out the asbestos air monitoring differs in relation to commercial and domestic premises:

  • For asbestos removal at commercials premises the person who commissions the asbestos removal is responsible for arranging person to determine the air monitoring.
  • For asbestos removal at domestic premises, the person engaged to do the asbestos removal work is responsible for arranging a person to carry out the air monitoring [2].

When is Asbestos Air Monitoring required?

Asbestos air monitoring is required on all removal of friable ACM's. Although air monitoring is not always required for the removal of bonded asbestos it is regarded as good occupational hygiene practice.

How and when is Asbestos Air Monitoring Performed?

Asbestos Air Monitoring can be carried out in two ways:

  • Exposure Monitoring
  • Control Monitoring

Air Monitoring can be carried out during asbestos removal called 'During Removal Monitoring' or on completion of asbestos removal works called 'Clearance Monitoring'. Further to this Air monitoring can also be carried out when no removal works are taking place called 'Background Monitoring'.

Exposure Monitoring

Exposure monitoring involves determining a person's risk to airborne asbestos by taking regular samples within the breathing zone which they are exposed to during a period no longer than a person's 8hr working shift. Exposure monitoring is used to reliably estimate a person's exposure to asbestos so that it can be compared with the national exposure standard. Samples are usually obtained by attaching a filter holder to the workers jacket lapel. The exposure monitoring shall be undertaken in compliance with the NOHSC (1995) "Exposure standards for atmospheric contaminants in the atmospheric environment" 3rd Edition and Code of Practice for the safe Removal of Asbestos 2nd Edition.

Exposure monitoring must be carried out to achieve:

  1. Asses the exposure of the worker to asbestos in accordance with the NOHSC (1995) exposure standards.
  2. To provide estimates of exposure for epidemiological investigations and for compensation and legal reasons [1].

For exposure to be carried out in a successful manner the procedures should be carried out to provide minimal interference with the work being carried and the results must be indicative of a workers exposure to asbestos fibres.

Control Monitoring

Asbestos control monitoring is used to determine the effectiveness of the control measures put in place to during work on asbestos containing material. Control monitoring uses static or positional air monitors at fixed locations to measure the level of airborne asbestos fibres. Due to the fact that Asbestos control monitoring is used to measure the effectiveness of the asbestos control measures the monitoring results should not be used for occupational exposures and cannot be used to compare with the national exposure standards. In relation to the Code of Practice for the Safe Removal of Asbestos 2nd Edition control monitoring should be carried out in the following locations:

  • Outside asbestos removal and encapsulating areas;
  • At the clean end of asbestos decontamination units;
  • Inside buildings, structures or ships which contain asbestos.

Further to this control monitoring can be used for clearance sampling.

Other actions required during control monitoring are set out in the Code of Practice for the Safe Removal of Asbestos 2nd edition.

Clearance Monitoring

Clearance monitoring is air monitoring carried out after the work on the asbestos containing material has been completed and the area decontaminated and dried a clearance inspection must be under taken by the occupational hygienist. According to the Code of Practice for the Safe Removal of Asbestos 2nd edition, clearance monitoring uses static or positional samples to measure the level of airborne asbestos fibres in an area after the work on asbestos has been complete.

.An area is cleared when the level of airborne asbestos fibres is measured as below 0.01fibres/ml. For anything above 0.01 airborne asbestos fibres per ml the following actions must be followed.

Fibres per ml Action to be taken
<0.01 Safe for Occupation
0.01 to 0.02
  • Identify sources of contamination and rectify issue;
  • Wet-wipe and vacuum with HEPA-filter equipped unit;
  • Perform clearance air monitoring of area; readings must be <0.01 fibres/ml for re-occupation.
  • Entry only with P2 respirator
0.03 to 0.05
  • Restrict access to affected areas to essential duties only; entry only with Class P2 cartridge type respirator for respiratory protection, disposable coveralls and booties for dust protection of clothing;
  • Identify sources of contamination and rectify issue;
  • Wet-wipe and vacuum with HEPA-filter equipped unit;
  • Perform clearance air monitoring of area; readings must be <0.01 fibres/ml for re-occupation.
>0.05
  • Seal and restrict all access to area;
  • Full clean up by AS-1 licensed contractor required wearing Class P2 cartridge type respirator for respiratory protection, disposable coveralls and booties for dust protection of clothing;
  • Wet decontamination procedures required upon exiting area;
  • Identify sources of contamination and rectify issue;
  • Wet-wipe and vacuum with HEPA-filter equipped unit;
  • Perform clearance air monitoring of area; readings must be <0.01 fibres/ml for re-occupation.

All clearance monitoring must be carried out in accordance with the Code of Practice for the safe removal of Asbestos 2nd edition.