2. 6. 6. Avoiding wood preservatives

The term "biocide" comprises herbicides (chemicals used against weeds), fungicides (against fungi), rodenticides (against rodents such as voles) and insecticides (against insects). The harmful organisms against which biocides are used range from animals to plants and microorganisms, as well as fungi and viruses. Biocides consist of a great variety of active ingredients. The substances that are mainly used in coatings are fungicides (for mould control).

In most cases, the use of biocides involves a certain risk for both the user and the persons exposed to the materials treated with biocides, as well as the environment. Before biocides are used, it should thus always be verified if they are actually necessary and whether the product chosen is suitable for the intended purpose. Whenever biocidal products are used, appropriate precautionary measures should be taken and observed.

Under the Act on Biocidal Products [BMLFUW 2000b] the use of biocides is explicitly restricted to a sensible, necessary minimum, also by combining physical, biological, chemical and other relevant measures. Wood used for façades, verandas etc., should not be treated with wood preservatives.

In the case of window renewal or repair, it should be verified whether blue stain protection is actually necessary.
The wood preservatives used should be safe for health and as environmentally friendly as possible.

Wood preservatives with active ingredients shall only be used if this is explicitly required. Chemical wood preservatives with active ingredients are not necessary for hazard class 3 if wood of resistance class 1 or 2 in accordance with DIN 68364 is used.

If wood preservatives with active ingredients are explicitly required, only substances listed in the Austrian directory of wood preservatives ("Österreichisches Holzschutzmittelverzeichnis") issued by the Association of the Austrian Chemical Industry, or the German directory of wood preservatives ("Holzschutzmittelverzeichnis") issued by Deutsches Institut für Bautechnik should be used, provided that such substances can be applied on coated surfaces. This has to be proved by means of a valid test certificate relating to the corresponding purpose of application.