Polychlorinated biphenyl (PCB) was used from the 1950s to the 1980s. For example, it was used in joint compounds for prefabricated concrete construction, in plastics, paints, capacitors, and transformers (e.g. of fluorescent lamps or washing machines).
PCB accumulates in human fatty tissue and also in breast milk. PCB is taken up via the breathing air. PCB can evaporate from building materials and building components and thus lead to high contamination levels of the room air. The vapor accumulates in other materials (e.g. carpets and curtains), making them become secondary sources.
The awareness that PCB is a toxic and carcinogenic chemical compound only developed step by step since the 1970s. In western Germany, the production of PCB-bearing substances has been prohibited since 1982. Since 1989 there has been a general PCB prohibition regulation in western Germany. For the first time precautionary and refurbishment values were defined. In 200,3 a PCB regulation was applied stipulating that all state buildings had to be investigated for PCB.
Limit values
In detail, the PCB Prohibition Ordinance (1989) defines the following precautionary and remediation values:
Buildings with air values of 3000 nanograms of PCB per cubic meter (ng/m³) must be refurbished immediately. From PCB values in the air of 300 ng/m³ on, precautionary measures have to be taken. That includes special cleaning (dusting off) and frequent airing.
These regulations are applied to rooms that are frequented by adults for up to 24 hours per day. In some federal states this value is adjusted to the time spent in the room, which means that at the work station the value for an immediate refurbishment for an 8-hour working day is 24/8*3000 ng/m³ = 9000 ng/m³, precautionary measures have to be taken at 24/8*300 ng/m³ = 900 ng/m³.
Protection for pregnant women
Pregnant women at the work station have to be particularly protected. This is derived from the Maternity Protection and Hazardous Substances Ordinances. Therefore pregnant women at work should avoid rooms with a PCB air value of over 900 ng/m³.
This value is not determined explicitly. It is a calculated value based on the precautionary value of 300 ng/m³ for which special protective measures for normal persons have to be taken. This value was defined as a limit for pregnant women for a 24 hour stay in the room. The following is applied for an 8-hour working day for a pregnant woman: 24/8 * 300 ng/m³ = 900 ng/m³.
Last Update: 8 February 2010
