Asbestos is the umbrella term for different fibrous crystallising minerals, which were used between 1904 and 1990 in different construction products.
Only with the passage of time the downside of asbestos was realised: between 1960 and 1970 asbestosis was discovered. Later on it became known that the exposition to asbestos increases the risk of developing lung cancer.
For the first time in 1971, a threshold value for asbestos was set in Switzerland. In 1989 the use of asbestos in Switzerland was prohibited in general. In 1992 the threshold for the acceptable asbestos contamination of the air at the workplace was reduced to 0.25 fibres per millimetre. Since 2003 the valid threshold is 0.01 asbestos fibres per millimetre at the workplace and 0.001 asbestos fibres for work places where the work does not involve handling materials containing asbestos.
Nowadays the knowledge concerning the connection between exposure to asbestos and the resulting illnesses is comprehensive. This circumstance entails the risk to presume the same knowledge for previous generations, which, however, they could not have had. Therefore, when today a judgement has to be made concerning whether a conduct in connection with exposure to asbestos was unlawful and culpable, said judgment must never be made on an ex post but always on an ex ante basis. Because only what was known or could have been known at the moment when the act was committed (or omitted) can be actionable.
The potential for release of the existing asbestos fibres is critical for the assessment of a health endangerment by asbestos products. With products containing loosely bound asbestos the release potential is typically higher than with products containing tightly bound asbestos. Therefore, in order to assess the risk, the distinction between products containing loosely or tightly bound asbestos can be considered.
Also, a building contaminated with asbestos is, per se, neither qualified as contaminated site nor as waste subject to disposal regulations. To this day, the owner of a building is not obligated to remove the material containing asbestos or to remediate the building(s) just because of the fact that said building contains asbestos. However, an obligation to take measures can nevertheless ensue for the building owners, employers, constructors and other involved parties. For example, rent, worker protection and construction legislation establish a specific responsibility. Furthermore, also the liability of property owners according to article 58 of the Swiss Code of Obligations can have a major influence on the asbestos issue, because the property owner is generally obligated to take the necessary steps to avert the danger. Accordingly, the property owner for damage caused by faulty maintenance. The latter must be taken into consideration also especially in view of sufficient cordoning contaminated installations, but also concerning possible emissions. On the basis of the mentioned legal bases, therefore, an obligation can probably be considered as established when the health risk resulting from materials containing asbestos is big enough, that the pertinent SUVA-regulations (Swiss National Accident Insurance Fund) or other occupational safety or health protection provisions are not complied with.