Mould: What is it

Mould in the corner of a room

Moulds are everywhere. All they need to grow is water and a source of food, such as cardboard or wood. As mould grows it releases spores.

Mould thrives where there is prolonged dampness. Bathrooms, basements, ceilings, and water-damaged walls are all potential hosts for mould. Mould’s hyphae grow into wood and drywall like roots.

The hyphae are not killed by bleach because bleach’s ion structure prevents chlorine from penetrating into porous materials such as drywall and wood. It stays on the outside surface, whereas mould has protected enzyme roots growing inside the porous construction materials. When you spray porous surface moulds with bleach, the water part of the solution soaks into the wood while the bleach chemical sits atop the surface, gasses off, and thus only partially kills the surface layer of mould while the water penetration of the building materials foster further mildew and mould growth.

Attic mould growth near a bathroom vent

Surfactants serve the purpose of significantly lowering the surface tension of water to allow a cleaning solution to penetrate porous surfaces.

HazForce Environmental utilizes a proprietary set of products to abate mould. An anti-microbial is first applied that kills all mould by penetrating deep into wood fibers and removes most stains on surfaces. A mould inhibitor is then applied to all surfaces to help prevent the existence and future regrowth of mould.

Although these products work well on surfaces such as wood and concrete, any drywall with mould growth is removed and disposed of.

What’s the Risk?

For most people, exposure to mould doesn’t cause any significant health effects. However, if a worker or occupant has a weakened immune system, the health effects can be severe. Mould can cause allergic reactions, asthma, pneumonitis, infections of the upper airway, sinusitis, or other lung infections. Workers and occupants of buildings subjected to long-term exposure are more likely to develop these health problems.

How to minimize the Risk

Prevention is the key to avoiding mould exposure. Always make sure that water leaks are fixed, and standing water is mopped up. Air flow is the natural enemy to mould therefore any area where moisture may accumulate should be well ventilated, and exhaust fans should be utilized wherever possible.

To prevent health problems, WorkSafeBC has developed requirements detailed in the Occupational Health and Safety Regulations that Hazardous Material Abatement Contractor’s must adhere to when conducting work around mould.