How to sterilize contaminated surfaces

To support micro-biological growth, moisture, a food source and protection from u.v. light are required. Be it a poorly ventilated bathroom, kitchen, the interior of a wine cellar or fruit pack-shed, these requirements are met, and the growth of fungus and/or algae can be expected. Standard specifications generally call for an initial dose of a fungicide, followed by cleaning to remove the sterilised debris before a second application of the fungicide immediately before re-painting. This specification is sufficient for areas where moderate fungal contamination exists.
Where contamination is high, and where the growth has been present over a long period of time - such as in wine cellars - it is often necessary to repeat the application of fungicide, followed by the cleaning step several times, until all of the growth has been removed. The 'second' dose of fungicide can then be applied and re-coating can commence. These areas should be viewed as 'high-maintenance areas' and these walls should be washed down on a regular basis - as soon as growth re-appears. Installation of u.v. light in these areas will also help to slow down and limit re-growth. The 'one spec fits all' approach cannot be adopted in all cases.
The top-coat applied in these areas should contain a dry-film fungicide to ensure that re-growth is retarded for as long as possible. There is no guaranteed growth-free period, even when all of the above steps have been meticulously followed, as the rate of re-growth is entirely dependant on the conditions in that specific environment. Following the above steps will, however, ensure that you get the maximum benefit for the effort and costs incurred.