Mould is a type of fungus that is found everywhere, outdoors and indoors. However, exposure to mould can cause health and safety issues.
Find out how to manage mould and stay safe.
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People can be exposed to mould through inhalation, skin contact or ingestion. The health effects include:
- irritation of the eyes, nose, throat and skin
- allergic reaction in people with a mould allergy (e.g. asthma flare-up or hay fever symptoms).
- hypersensitivity pneumonitis—a rare lung disease where the lungs become inflamed due to an allergic reaction to certain inhaled substances (e.g. organic dust, fungus, mould or chemicals)
Most healthy people will not experience health problems from contact with mould, however the risk increases for people with:
- asthma, allergies or other respiratory conditions may be more sensitive to mould
- a health condition or undergoing medical treatment that lowers their immunity are more at risk of infection (e.g. cancer and its treatment, organ transplant recipients).
Workers at an increased risk should avoid mould affected areas and consult their doctor if they are concerned about mould exposure.
Preventing mould growth
Mould is not usually a problem in indoor environments unless there is a source of water or excess moisture that allows it to grow. Mould growth in buildings can be prevented by controlling water intrusions and excess moisture. For example:
- keep mould-susceptible building materials dry during construction
- ensure adequate drainage around buildings
- regularly inspect and maintain the building and its fixtures and undertake repairs promptly to prevent water damage
- maintain heating, ventilation and air-conditioning (HVAC) systems and make sure these are set to the environmental conditions
- manage water vapour and condensation, especially in high water vapour areas such as bathrooms and showers
- clean up wet areas and water damage promptly (within 24-48 hours).
Seek professional advice to manage water and excess moisture problems.
Mould remediation involves assessing the mould issue, fixing the underlying cause of the mould growth¸ cleaning mould contamination and managing potentially contaminated dust. Consider using a professional service that specialises in mould remediation.
Assess the mould issue
Assess the mould issue by looking for evidence of water intrusion, excess moisture or mould growth. This may be hidden, such as behind furnishings or in building cavities. Activities such as drilling inspection holes in walls to look for water damage or mould growth may disturb mould and cause it to spread to other areas, if not properly managed.
Be aware of other health and safety issues when investigating mould issues, including sewage contaminated floodwater, hazardous chemicals, asbestos, confined spaces, lead, electrical hazards and pests, for example rodents.
Fix the cause of the mould growth
Identify and fix the underlying water or excess moisture problem that is causing the mould growth, or the problem will return.
Cleaning mould contamination
- Restrict access to the affected area and where possible schedule the work for when the building is not being used.
- If there has been water intrusion, dry out the wet area as soon as possible. Fans, wet vacuums, dehumidification units, heaters or air-conditioners on dry mode can be used to speed up the drying process.
- Thoroughly clean contaminated hard surfaces and materials using water and detergent (soapy water) or a vinegar solution and dry completely. Clean all tools and equipment after use.
- Discard porous materials (e.g. ceiling tiles, plasterboard, insulation and carpets) that can't be readily cleaned, have been wet for more than 48 hours or have visible mould growth. Seek professional advice about restoring damaged items that are valuable or irreplaceable.
- On completion, do a final clean-up to remove any dust that may have settled within the affected area or nearby.
It is important to properly capture, contain or suppress potentially contaminated dust to prevent mould spreading to other areas. Control measures will depend on the extent of mould contamination and disturbance:
- Isolate the affected area:
- Shut doors and windows leading to other work areas.
- Seal supply and return air vents or shut down the HVAC system servicing the area.
- Use floor to ceiling plastic sheeting with sealed edges.
- Where a higher level of containment is needed, set up a negative pressure enclosure and incorporate a decontamination chamber.
- Prevent dust becoming airborne:
- Use cleaning methods that minimise dust (e.g. spray contaminated materials with a mist of water before disturbance, use a H class industrial vacuum (PDF, 0.62 MB) ). Dry sweeping, household vacuums and compressed air generate large amounts of dust and should be avoided.
- Use ventilation controls (e.g. fit power tools with H class dust extraction, use a HEPA-filtered air scrubber).
- Contain mould-contaminated materials and debris prior to removal for disposal or decontamination off site.
Specific guidance is available to manage construction dust at healthcare facilities to protect vulnerable patients from mould exposure.
Post remediation evaluation and verification
Post remediation inspection and evaluation can be conducted to ensure that risks from mould have been adequately addressed. Consider using a professional service, independent of the remediation service provider, to verify that the remediation was successful.
Personal hygiene practices
Workers who work with mould should wash their hands thoroughly with soap and running water:
- before eating, drinking and smoking
- after contact with mould
- after removing PPE.
Workers must be provided with washing facilities (PDF, 0.7 MB). This should include clean running water, soap and paper towel or an air hand dryer. Field workers should be provided with portable hand washing facilities.
Information, training, instruction and supervision
Provide workers with information about:
- health risks from work with mould
- safe work procedures
- proper selection and use of PPE.
Communicate with building owners, managers, occupants and tenants about mould issues and remediation work.
Personal protective equipment (PPE)
Wear PPE to protect against exposure to mould and to prevent the spread of mould to other areas.
For low risk situations this should include:
- a properly fitted (PDF, 0.86 MB) particulate respirator (P2 or higher)
- disposable gloves.
For higher situations this should also include:
- protective clothing
- safety eyewear
- shoe/boot covers.
Take care to avoid heat stress when wearing multiple items of PPE, especially when working in hot and humid conditions.
Contact Workplace Health and Safety Queensland on 1300 362 128 for more information about mould.
Contact Queensland Health on 13HEALTH (13 43 25 84) for information about dealing with mould after a storm, flood or cyclone. Seek advice from your general practitioner if you have concerns about possible exposure to mould.
Australian Mould Guideline (AMG 2010), 2nd edition, Kemp P and Neumeister-Kemp H, 2010