In Switzerland, materials used in construction in the past have introduced substances that are toxic to humans and their environment. Some of these substances are now banned – asbestos, PAHs, PCBs and lead – but are still present in many buildings. For residents and users, the risks of exposure are limited. On the other hand, the danger of contamination is high in the event of work. Renovating, transforming and demolishing according to the rules of the art is essential to avoid any damage to health. A diagnosis of building pollution is required in many cases.
The year a building was built or renovated is a good indicator. Indeed, buildings built after 2006 are not affected by pollutants. The table below summarizes the risks of toxic materials based on the years of construction.
Polychlorinated biphenyls (PCBs) are found in expansion joints and seals, as well as in electrical capacitors. Asbestos is a mineral fibre once used extensively in buildings for its fireproofing, insulating, flexibility and strength properties. It has been banned in Switzerland since 1990, but is still present in nearly 80% of Geneva’s buildings. It is found in fibrocement sheets, bituminous waterproofing, facade coatings, joints, tile and earthenware adhesives, vinyl flooring, etc. Polycyclic aromatic hydrocarbons (PAHs) may be present in old asphalt layers and in bituminous insulation in slabs and roofing.
As for lead, it was added to paints as a pigment or to give them anti-corrosion properties. It is found just about everywhere, from facades to painted woodwork, through wall paints, radiators and finally pipes.
Significant amounts of toxic substances can be emitted during work to renovate, remodel or demolish. Thus, as long as the substances are not handled, there is no danger: there is no risk of breathing in toxic fibres or dust. Before starting work on buildings dating from before 1991, the owner or contractor must first have them checked for asbestos or PCBs. This research is compulsory, whether or not the work is subject to a building permit. On the other hand, for work on paints dating from before 2006, it is necessary to ensure that they do not contain lead: a specialist will carry out a diagnosis.
A certified expert makes an inventory of materials that may contain hazardous substances. He takes samples and sends them to an approved laboratory for analysis. A detailed report, as well as a certificate of the hazardous substances (to be attached to any request for a building permit) are provided to the applicant. The price of the expertise varies according to the analyses. This diagnosis – generally carried out within 48 hours – states the contaminated materials. If this is not the case, the work can start without further delay. If, on the other hand, the building contains toxic substances, a specialised company is commissioned and the site is closed off. The polluted waste is sent to specific disposal channels.
An independent expert must then be appointed.
An independent expert must then carry out air measurements (VDI 3492): filters pump the air from the site for eight hours, before being sent to a laboratory. S’there are no harmful fibres or dust, work can begin.
Although not mandatory in the canton of Geneva, an analysis of pollutants allows you to know the condition of an apartment or house before putting it up for sale. This diagnosis is particularly useful for properties built before the 1980s. It provides some security to potential buyers, and even increases the value of the real estate in question.
State of Geneva
Servimmob SA – building pollutant diagnosis