What to do in case of mould infestation?
If the sanitation activities cannot be started immediately, check whether the affected areas can be temporarily cleaned and disinfected without dust turbulence (e.g. with 70 % ethyl alcohol for dry surfaces and 80 % ethyl alcohol for damp surfaces) or whether there are possibilities to temporarily cover or seal off the affected areas.
The protective measures described below must also be observed for these temporary measures.
The use of the frequently quoted vinegar solution is usually not a good idea, as many building materials, especially lime, neutralise and, in addition, organic nutrients get onto the material with the vinegar. The use of fungicides in the interior is also not recommended.
Targeted ventilation and heating of the affected area can reduce moisture and further mould growth. However, this measure may only be carried out if previously existing mould spores have been removed in order to avoid high concentrations in the room air and the development of secondary sources.
By increasing ventilation and heating as well as by moving the furniture away from external walls, the risk of falling below the dew point in the room can be reduced and thus further growth of mould can be prevented. This measure also only makes sense if previously existing mould spores have been removed.
The sanitation of mould infested materials must have the goal of completely removing the moulds. A mere killing of moulds is not enough, because even killed moulds can cause allergic and irritating effects.
In the case of smooth surfaces (metal, ceramic, glass), the moulds can be removed with water and normal household cleaner. Infested porous materials (wallpaper, plasterboard, porous masonry, porous ceiling formwork) cannot be cleaned. Easily removable building materials such as plasterboard or lightweight partition walls must be dismounted and removed. Moulds on building materials that cannot be degraded must be completely removed (i.e. also in deeper layers).
In the case of wood, a fundamental distinction must be made between so-called wood blueness (superficial infestation during wood processing caused by the fungus Aureobasidium pullulans) and the active growth of mould due to acute moisture damage with strong sporulation of the mould fungi. With normal wood blueenes there is usually no need for renovation.
Actively infested wood, on the other hand, is very difficult to renovate and usually has to be disposed of. In exceptional cases superficial infestation can be removed by grinding. Infested furniture with a closed surface (chairs, cupboards) must be cleaned damp on the surface, dried and, if necessary, disinfected with 80 % alcohol (note the risk of fire and explosion as well as personal respiratory protection).
Heavily infested furnishings with upholstery (armchairs, sofas) can rarely be reasonably renovated and should therefore normally be disposed of. Infested household textiles (carpets, curtains) can also usually only be properly repaired at great expense, so that disposal is preferable depending on the acquisition costs.
During the sanitation of mould infestation on materials, very high concentrations of spores can be released. Refurbishment should therefore only be carried out by professionally qualified persons under suitable safety and industrial safety conditions. Furthermore, it should be noted that a health risk cannot be excluded, e.g. for allergy sufferers or previously injured persons with chronic respiratory diseases and for persons with a weakened immune system, so that this group of persons should not carry out any remedial work.
Small-scale remediation work (e.g. only superficial infestation, infested area not larger than approx. 0.4 m2, no structural defects), for which no risk to healthy persons is to be expected, can generally be carried out without the involvement of specialist personnel, whereby the use of prior expert advice is recommended.
The following procedure can be used as an example:
Infested wallpaper or silicone joints can be removed, superficially infested areas wiped with a damp cloth or vacuumed with a vacuum cleaner with a fine dust filter (HEPA filter) and treated with 70 – 80 % ethyl alcohol, taking into account the risk of fire and explosion (use only small quantities, ventilate well, do not smoke, no open fire) and the requirements of occupational safety (protective gloves, mouth protection, safety goggles). After remediation, fine dust particles (fine cleaning) must be removed in the vicinity of the remediated areas. The mould contaminated waste produced during the renovation can be disposed of with the household waste in plastic bags.
Protective measures for small-scale remediation measures
Do not touch moulds with bare hands, wear protective gloves.
Do not inhale mould spores, wear a mouthguard. Do not let mould spores get into the eyes, wear dust-protective glasses. After the renovation shower and wash clothes. *
More extensive renovation work should be carried out by commercial companies. For this purpose, companies must be commissioned that are familiar with such remediation work, the risks involved, the necessary protective measures and the regulations and recommendations to be observed.
*A very simple and effective method to prevent the formation of mould on walls is the use of lime plaster or lime paint. Since lime is strongly akalisch, molds cannot live on it.
Silver particles in wall paint ensure mildew-free rooms
The Fraunhofer Institute for Chemical Technology in Karlsruhe has developed a wall paint in conjunction with the Bioni company in Oberhausen to permanently prevent the formation of mould in interiors and the growth of algae on facades.
The reason for this wonderful property is the nanometer-sized silver particles, which are processed homogeneously in the paint. The silver particles release ions which, in contact with the germs, whose nutrient-transporting enzymes block, destroy proteins, couple them to the genome and disrupt cell wall synthesis.
According to the scientists, 1 gram of silver would be enough to kill all germs in 10 kg of paint.
Additve prevents the silver particles from clumping together in the paint, while polymers ensure that the particles remain embedded in the paint and are not released into the room air. This is a decisive advantage over the previously used anti-fungal paints, which release dangerous biocides and fungicides into the environment. As silver particles are also known to severely restrict the growth of bacteria, the new paint is now also being tested in hospitals.
FAZ from 25.01.2006