Mould Removal Decontamination and abatement
Mould spores are absolutely everywhere on the planet and will always be found, therefore total mould removal is unnecessary. Mould removal is dependent on identifying all mould sources, including those that may be hidden and should never be undertaken until the causation or moisture issues have been resolved.
Building Forensics provide client and or contractor with detailed protocols for mould removal and third party monitoring which assess both control during removal to prevent the spread of spores and the use of adequate protocols to ensure all aspects of contamination have been addresed.
Mould removal fallacies
Where moisture is present more than a few days mould will usually develop, but unfortunately, most mould is hidden within in new construction cavity walls or behind surface coverings, where environmental conditions are more conducive to growth. This means visible growth is usually only a very small part of the total problem.
The washing off of mould with bleach and fungicide is almost universally accepted as a wrong where a moisture issue exists and painting over mould affected surfaces can simply be seen as camouflaging the problem.
Mould removal should not be confused with decontamination where some of the most toxic chemical and microscopic contaminates may remain and may require highly specialised decontamination. See decontamination section.
Mould growth inside buildings is always the result of water damage, in any form, from condensation, leaks and flooding subject to suitable environmental conditions (food and temperature). Other contaminates apart from mould may be present too, including bacteria. Mould and bacteria will combat for available food and territory and release some of the most toxic chemicals known to man. These chemicals are designed to kill other life forms and as humans are a biological life form they too may be affected. You will note I have emphasised the chemical release, known as mycotoxins as the hazard and this is key in decontamination.
The photo identifies missing insulation and leaking bathroom extract and was simply and economically resolved.
While some moulds can invade lungs and be parasitic, living of other life forms, such as Asperigillus, the major issue is the mycotoxin or toxic chemical held inside the spore which is released either when the spore is under attack or killed. The dead spore case will fracture, releasing all of its chemical content onto the tiny spore case fragments. These sub micron particles can easily be inhaled to deep lung where they can enter blood stream through the alveoli and result in disproportionate health effects.
It is therefore clear that quite apart from mould spores, other possibly pathogenic contamination should be considered as being present and which requires removal. Building Forensics provide independent assessments of contamination using state of art but economic technology and American laboratories in preference to UK as they usually provide more accurate, economic and faster results.
As mould is both toxic and allergenic and all humans have different tolerances to exposure no international guidelines are available for safe exposure. Some literature suggest that a maximum of 350 spores per cubic meter of air is a maximum but this quantity would depend on both the type , genus, of the mould and the individuals immune system. With a cubic inch of mould likely to contain 1 billion spores it can be seen that even small amounts of mould can be a health threat to some.
Sometimes mould decontamination requires extensive intrusive demolition to remove hidden contamination, but justification and evidence must be provided.
Mould decontamination in USA
Building Forensics developed its skills from working and studying mold related issues in USA where mold claims outstrip asbestos claims in the courts. The reason mold issues are so prominent in USA is possibly due to high profile claims in terms of celebrity success and multi million dollar court awards for health or building defect compensation. The American legal profession has driven the need to provide scientific evidence of contractor or landlord competence in mold decontamination or building defect and responsibility for mold and resultant health hazards. Building forensics use long standing relationships with US based laboratories to provide state of art scientific support and provides its clients with accurate and objective assessments. The following photo log provides an insight of how America sees the health hazard and liability of mold and it should be accepted that the same mold, health and liability issues exist in the UK.
This property affected by mould in USA required total gutting to achieve required clearance of ambient spore counts.
Building Forensics have wide experience in supporting clients with compensation claims against contractors who provide inadequate or delinquent decontamination methods.
Contractors advertising mould and soft demolition services to mould affected areas in New Orleans
The forgoing was discussed to enable the debate on decontamination.
Killing mould is quite easy, remove the moisture or dry out mould affected surfaces, but as can be seen, this is likely to make contamination worse.
Painting over mould even with mould resistant paints is seen as a short term solution and inevitably mould will be killed and spread through aerosolisation. Once established on a surface mould is likely to re grow even on the fungicidal paint, subject to certain conditions.
Bleach can be used for small areas only but soapy water for removal is a far better option on non porous surfaces.
Professional mould removal
Building Forensics provide all necessary independent third party support to ensure the following steps are addressed.
Professional mould removal and decontamination will follow logical steps.
1.Assess the total damage, not just visible mould.
The majority of mould may be hidden in cavities or behind wallpaper, the mould may be dead and surfaces dry due to a historic, but now dry leak. Investigation is important because decontamination of only one of several areas is a waste of time and money. Investigation may include moisture mapping, assessments of historic damage, perhaps intrusive investigation and air sampling. Building Forensics use state of art technology in these processes which include the use of pressure variables, trace gas, infra red cameras and a host of specialised moisture measurement equipment to pin point damage.
2. Mould measurement
If you have visible mould there really is no reason to sample it unless there is a possibility of subsequent legal issues or your doctor requires specific information on its type for treatment purposes. All mould is allergenic and some toxic, so if its visibly present, it shouldn’t be. The problem really Is what about hidden mould and this may take investigation, equally some may say this is a normal amount of mould, and therefore, quantification and speciation is necessary.
3. Mould testing
There are many types of mould investigation and testing but unfortunately only a few ways to assess reasonably accurately as all techniques have their own limitations. Building Forensics follow recommendations of the “World Health Organisation Guidelines on Damp and Mould 2009” and have been using these “Total Spore Count” techniques for over 10 years. Building Forensics were also amongst the first UK company to utilise the new “PCR DNA”
It should be noted that the WHO specifically state that the historic use of SAS or culture based sampling, (Petri dish) is extremely flawed and cannot provide the necessary information.
The sampling data can be used as a reference to determine the success of decontamination.
4. Stop the water source
If the environmental conditions exist even after the most competent decontamination, mould will return. Building Forensics undertake independent moisture and environmental investigation to identify causation of moisture and will recommend solutions to stop or mitigate or remediate these issues. Building Forensics use infra red thermography and ultrasonic measurement with a range of specialist equipment to identify or prove the cause of moisture. Lifestyle issues almost always stated as a cause of condensation is invariably found to be false and building design or construction defect is more often causation.
5. Containment
Depending on the extent and level of contamination, containment or tenting may be required to prevent spore release affecting other parts of the property. This containment may have to be under negative and sometimes positive pressure. Building Forensics can provide assistance in the design or erecting of containment
6. Standard of decontamination required
As previously mentioned, total mould or contamination removal is not practical or possible. The expected or required level of decontamination should be agreed prior to the start of the project to avoid unnecessary cost, time and disappointment or dispute. These levels will need to be established by a third party such as Building Forensics, who will assess the requirement of the client and protocols of the contractor. Building Forensics can also provide support in monitoring and guidance during the process.
7. Clearance
Prior to decontamination the required level of decontamination must be established. Failure to assess this level could result in unnecessary work and cost or more significantly total failure in expectations. There are different ways to determine if decontamination has been successful and they revolve around quality controls, measurement and comparison . Building forensics can provide independent third party appraisals and verification of decontamination.See our section on toxicology and mould sampling