Mould clean verification after service leak

Under some unfortunate circumstances properties can suffer from a catastrophic failure of building services which can results in destruction of finishes and contents as well. I have recently completed a project where such catastrophic failure occurred. Relatively minor leak of a bathroom pipe has resulted in flooding of wall cavities with water. The significanly elevated humidity inside of numerous cavity walls has caused massive hidden mould contamination.

The owners did not realise that the house was suffering serious mould problem until some of the occupants suffered serious and sudden health problem. The hidden contamination was so severe that one of the people involved had to be hospitalised and one house pet unfortunately died.
Initial examination of the property by major flood restoration company has identified the area of the leak and extent of the problem. The property has been vacated and mould removal project which included removal all partition walls, ceilings and some floors have been initiated.

Wall cavity mould contamination test

Wall cavity mould contamination test

Building cavity mould sampling

Building cavity mould sampling

I have been invited to participate in the project at various stages but mainly in advisory and quality control role. I have carried out cavity sampling thorough the property to find out any other sources of contamination which may have been missed by the contractor. The sampling regime was quite extensive and included well over 90 mould spores samples collected from various building cavities. Based on the investigation the scope of the project had to be extended to include several new areas.

Main contractor then took over the site and carried out decontamination following his own flood restoration guidelines with no input from concerned sites. After the completion of decontamination I have carried out thorough inspection of the property. The inspection was aim to assessed the effectiveness of the deep clean and to evaluate the composition of the indoor air in regards to mould spores.

Dust on top of items

Dust on top of items

It has obvious from the onset of the inspection that the flood and restoration contractors did not understand the meaning of a “deep clean” I have identified multitude of areas still contaminated with debris of various types including several bucked full of building rubble, dry rat, dead bird, dust and debris throughout the property.

Various mould decontamination failures

Various mould decontamination failures

The inspection was followed by mould spore sampling which fortunately showed normal levels of fungal spores. However due to the completely unsatisfactory completion of the clean the clearance verification has failed and the property had to remain closed off. Naturally the contractor argued that the quality of the clean was satisfactory but a visit from an insurance loss adjuster quickly put any argument to an end. With short time of him visiting the site he has himself declared the clean as unsatisfactory and the contractor was asked to leave the project.

Airborne mould spores clearance testing

Airborne mould spores clearance testing

The main failure of the flood and restoration contractor was the lack of understanding of the situation and in particular the requirements of mould decontamination. Many contactors do not understand that decontamination, deep clean and restoration clean are not interchangeable terms but each has a very specific meaning and requirements.

By Tomas Gabor

Link through to Sysco - Nationwide specialists in hazard exposure monitoring
Hi, I have been working in my job as an Indoor Air Quality Investigator for a number of years and decided to share my experience with you. You can find lot of related information on my website toxic black mould
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