Mould can be visible in badly ventilated rooms such as walls, ceilings contents and carpets. Mould affects the indoor air quality that can affect the respiratory system coursing nazal congestion, wheezing, chest tightness coughing and throat irritation. Mould lies dormant as a natural part of the ecological environment to break down non-living organic matter. By the addition of high levels of moisture the breaking down process is enhanced.
The causations of mould growth in a building is from –
Faulty construction (plumbing and roof leaks)
Weather events (excessive rain and rising ground water flooding)
Over watering outs side gardens and indoor plants.
Lack of ventilation in bathrooms, laundries and kitchens.
Other areas in a property may be affected by the above causation due to high humidity levels and mould spores being cross contaminated throughout the property.
Conditions classifications of mould growth
Condition 1 – This is the benign state of non – hazardous levels of mould. In mould remediation condition 1 is the level to be achieved.
Condition 2 – The indoor environment is contaminated by settled mould spores with-out active growth that has cross contaminated on other areas of a building and contents. Can be HEPA vacuumed and cleaned.
Condition 3 – These areas are contaminated by active or dormant mould growth that is visible and does not pass hygiene standards. Requires demolition of affected structural porous materials such as plaster, carpet and insulation.
Physical abrasive cleaning of semi – porous materials such as brick, concrete and wood framing.
Non – porous materials such as glass, metals and granite can be treated with HEPA vacuuming and damp wiping.
Mould can thrive in materials building such as wet plaster walls, carpet, insulation and timber frames. The organic materials in plaster with the cellulosic coating make it an ideal environment for mould to grow.The EPA suggests that the interior air relative/humidity level in a property should be kept below 70% to minimise mould growth.
In materials mould can grow when the moisture content reaches up to and greater than levels of 16 – 20% in materials..
If your house has been wet and left to dry naturally over 48 – 72 hours the mould and bacteria will have been activated for growth.It been common that when a flood occurs from a bathroom into a carpet in an adjoining passage that the resident just soaks it up with towels. In a few days the carpet may appear dry but the underlay will remain wet for a long time. This is a haven for mould growth on the backing of the carpet and around the smooth edge.
When the carpet is folded back due to another flood it is reveals the black mould on the backing. The only way to rectify this is by replacing the carpet.
Exposure to mould/sewage health affects –
The route of exposure to moulds is through inhalation or breathing in spores and hyphal fragments. Our skin protects us against mould spores most of the time. It does not matter whether spores/hyphal fragments are viable or non-viable in activity they still cause the same reaction through inhalation. Some moulds under ideal conditions can produce metabolites from the degradations of substrates MVOCs.Mycotoxins are complex chemical toxins that can be inhaled through the skin, some of which have serious health results. The theory is that some moulds produce mycotoxins to fend off other moulds that look to invade their food source. Some mycotoxins are carcinogenic, such as aflatoxin. Aspergillus flavus has been known to produce this aflatoxin from rotten peanuts and other foods. Stachybotrys is another known mycotoxin producer that found in the bacteria wall of the spore/hyphae.
Stachybotrys chartarum is a hydrophilic mould that loves to grow on continuously wet plaster walls and other absorbent materials. It is a slow grower generally taking 7 – 12 days to grow and is sticky due to the mucus enzymes it produces.Please contact us for any mould concerns.