Incidents involving high-pressure water spray equipment on asbestos roofs

Two recent incidents involving the use of high-pressure water spray equipment on asbestos roofs have resulted in asbestos contaminated dust or debris (ACD) being spread across each of the sites in addition to neighbouring properties.

Investigations into both incidents are continuing.

Safety issues

Asbestos is most dangerous when it’s deteriorating, damaged or disturbed. Cleaning asbestos cement roofs, fences and walls with high-pressure water spray equipment can destroy the binding matrix of asbestos containing material (ACM), resulting in cement debris, airborne asbestos fibres and widespread contamination.

Disturbed asbestos fibres that resettle on surfaces stick to everything including walls, plants, garden soil and lawns and are very easily disturbed again. These fibres remain for years if not decades if the contamination is not remediated.

Asbestos is common throughout older homes, built before 1990 – and not just the roofs.

Ways to manage health and safety

Effective risk management starts with a commitment to health and safety from those who manage the business. If an incident occurs, you'll need to show the regulator that you’ve used an effective risk management process. This responsibility is covered by your primary duty of care in the Work Health and Safety Act 2011.

Use the hierarchy of controls to help decide how to eliminate and reduce risks in your place of work. The hierarchy of controls ranks types of control methods from the highest level of protection and reliability to the lowest. It’s a step-by-step approach to eliminating or reducing risks. You must work through the hierarchy of controls when managing risks, with the aim of eliminating the hazard, which is the most effective control.

Possible control measures to prevent similar incidents

You should never use high-pressure water spray equipment to prepare for painting, coating or sealing of asbestos containing materials as there is no system of use that can effectively capture or suppress asbestos fibres in such circumstances. It is illegal to use high pressure water spray equipment on asbestos, including asbestos cement roofs, soffits, fences, pipework and walls.

A PCBU must not use, direct or allow a worker to use high pressure spray on asbestos or ACM. Before carrying out maintenance of a roof, consider whether asbestos could be present. When working on buildings constructed before 1990, it is likely asbestos could be present in roofing and other building elements.

Identifying asbestos or ACM is the first step in managing the risk of exposure to asbestos. This must be done by someone with the proper training, qualification and experience. As there may be more than one person in the workplace responsible, it is important all duty holders consult, cooperate and coordinate with each other as well as consulting with workers and health and safety representatives.

If asbestos has been found, the next step is to perform a risk assessment. This will help to figure out:

• if there is a risk your workers could be exposed to airborne asbestos
• whether any effective control measures are in place
• what actions you can take to control this risk
• how urgently you should act.

After assessing the risk of exposure to airborne asbestos in your workplace, you’ll need to implement control measures. You may need to use a combination of these controls in order to meet your responsibilities under WHS laws.

PCBUs must always aim to eliminate the hazard and associated risk first, for example by removing the asbestos sheeting. If the asbestos or ACM in your place of work is posing a serious risk, you should remove it. The How to safely remove asbestos code of practice 2021 sets out how to remove asbestos including requirements for inspections, removal, transport and disposal.

If it is not reasonably practicable to remove the asbestos, then other control measures must be implemented to ensure people are not exposed to airborne asbestos. This may involve a single control measure or a combination of different controls that provide the highest level of protection. The How to manage and control asbestos in the workplace Code of Practice 2021 provides practical guidance to PCBUs on how to manage risks associated with asbestos, asbestos containing material (ACM) and asbestos-contaminated dust or debris (ACD) at the workplace

These can include but are not limited to the following.

Encapsulating

Asbestos that is encapsulated in a resilient matrix (in reinforced plastics, vinyls, resins, mastics, bitumen, flexible plasters and cements) has little opportunity to release airborne asbestos unless the matrix is damaged. This type of encapsulation will seal any loose fibres into place and should be used only when the original asbestos bond is still intact. If encapsulation is recommended, the person carrying out the work should:

• be trained and experienced in working with asbestos
• hold the appropriate licences
• isolate the area
• use suitable RPE that complies with AS/NZS 1716: ;Respiratory protective devices
• wear suitable protective clothing such as disposable overalls
• follow a safe system of work that reduces the risk of creating airborne asbestos
• follow a decontamination procedure upon completion of the task.

Sealing

Sealing is the process of covering the surface of the material with a protective coating over the asbestos to prevent exposure to airborne asbestos. The process either coats the material, reducing fibre release, or binds the fibres together. Asbestos should be sealed, coated or painted to protect it.

There are alternatives available for cleaning Super Six and other ACM containing roofs, these include the use of specially designed fungicides, primers and coatings for use on ACM roofs. By utilising this method, the ACM surface is treated and sealed while minimising the risk of disturbing and releasing airborne asbestos fibres from the roof surface. Sealing asbestos is the least effective method for controlling the release of airborne asbestos.

Workers will need to use personal protective equipment (PPE) in combination with other effective control measures when working with asbestos. Your selection and use of PPE should be based on your risk assessment. PPE includes but not limited to:

• disposable coveralls (disposable coveralls with fitted hoods and cuffs should be worn and need to be of a suitable standard to prevent penetration of asbestos fibres - disposable coveralls rated type 5, category 3 (EN ISO 13982–1) or equivalent would meet this standard)
• footwear boot covers and gloves (laceless boots such as gumboots are preferred where practicable and if boot covers are worn, they should be of a type that has anti-slip soles to reduce the risk of slipping)
• gloves, which should be determined by a risk assessment (if significant amounts of asbestos fibres may be present, disposable gloves should be worn). Any gloves used must be disposed of as asbestos waste regardless of the amount of asbestos present.
• respiratory protective equipment (RPE). The selection of suitable RPE depends on the nature of the asbestos work, the probable maximum concentrations of asbestos fibres that would be encountered in this work and any personal characteristics of the wearer that may affect the facial fit of the respirator (e.g. facial hair and glasses). A competent person should determine the most efficient respirator for the task.

Administrative controls can be used to minimise any remaining risks (e.g. safe work practices) and can include work methods or procedures designed to minimise exposure to asbestos fibres as well as the information, training and instruction needed to ensure workers can work safely. Workers who are required to conduct asbestos-related activities and wear PPE must be given adequate training and supervision to enable them to fit and use the equipment correctly and conduct the task in a safe manner.

Tag your equipment to warn others not to use water blasters on asbestos containing material. See Figure 1.

Figure 1: Prohibited use of water blasters tag poster

Administrative controls and PPE are the least effective at minimising risk because they do not control the hazard at the source and rely on human behaviour and supervision. These control measures should only be used:

• to supplement higher level control measures
• as a short term interim measure until a more effective way of controlling the risk can be used, or
• when there are no other practical control measures available.

The control measures you put in place should be monitored and reviewed regularly to make sure they work as planned.

Prosecutions and compliance

Incident 1

In March 2024, a painter and his company were found guilty of three charges for breaching the Work Health and Safety Act 2011, after the painter used high-pressure water spray to clean an asbestos roof in preparation for painting.

The company had a conviction recorded and was fined $37,500, in addition to $31,906.60 for the cost of remediation works. The painter also had a conviction recorded and was individually fined $8,000.

Incident 2

In December 2023, a person conducting a general handyman business and one of his workers were fined for breaches of Queensland’s work safety laws by failing to ensure the health and safety of others and allowing a worker to use a high-pressure water sprayer on asbestos materials.

The handyman business was fined $5,000 with a two-year court ordered undertaking under the WHS Act in the sum of $25,000. The worker was ordered to undertake 60 hours of community service to be completed within 12 months in addition to a two-year court ordered undertaking under the WHS Act in the sum of $15,000.

Incident 3

In April 2024, the owner of a cleaning business was fined $3,000 and ordered to pay over $50,000 in restitution for use of high pressure water spray on an asbestos tiled roof.

The use of the high water pressure spray on the asbestos tiles caused disturbance and breakage to asbestos containing material (ACM) in the cement tiles, creating airborne asbestos containing dust and debris (ACD) particles to be distributed throughout the workplace.