When buildings and vehicles become wet due to severe storms or earthquakes, it is common that mould will grow in the days and weeks afterwards.

Exposure to mould can be a risk to health and should be dealt with as soon as possible.

Those who are immune-compromised or already sick are at a higher risk of health problems. Normally, health problems will go away once the person is removed from the mould exposure. If a person is potentially affected by mould exposure in the workplace it is often best to find an alternative place for them to work until the mould issues has been investigated and fixed.

How to prevent mould growing

Mould requires moisture to grow. Some steps you can take are:

• Clean and dry all materials out as soon as possible.
• When drying, ventilate the area so that moisture is not trapped inside.
• Check if materials are dry (if available, use a moisture metre).
• Remove materials if they are not able to be cleaned or dried.
• Fix all leaks as soon as possible so that materials do not get wet again.

Remember that mould is not always visible so it may still be there waiting for the right conditions to grow.

Cleaning and removing mould

When dealing with mould contamination it may be best to seek advice on its removal, including whether to employ a professional cleaner. You can find professionals in mould assessment on the Health and Safety Association of New Zealand (HASANZ) register.

Find an appropriate adviser | HASANZ Register(external link)

When cleaning or removing contamination

• Cover up as much as possible, and use personal protective equipment (PPE) like coveralls; gloves; safety glasses, goggles, or face shields; masks such as a P2 disposable respirator or half-face respirator with P2 filters.
• Avoid spreading the mould through areas that are not contaminated. Wrap contaminated materials in plastic or use bins to move it.
• Avoid using water blasters as this can cause mould to become airborne. Wipe surfaces down with microfibre cloths and vacuum using a high efficiency particulate air (HEPA) filtered vacuum cleaner.
• Regularly take breaks and make sure you wash your hands and face with soap before eating, drinking, smoking, or vaping (hand sanitiser may not work).
• If you cut yourself or break the skin, stop work and apply first aid including cleaning the wound. Seek medical attention if you think it might be infected or if the cut is deep.

When you are finished

• Remove PPE and dispose of it, or place items to be cleaned in a separate bag to be sealed.
• Immediately wash hands, arms, and face with warm soapy water. When able to, shower using soap to remove any mould that may still be on you.
• Wash all clothing used separately from regular laundry. Consider wearing a mask and gloves when removing it from the bag it is stored in, especially if the clothes are muddy or dusty.