For over ten years now, Energiewerke Nord GmbH (EWN) has been relying on Tyvek® protective coveralls from DuPont to protect its staff during demolition of the decommissioned nuclear power plant at Lubmin on the Baltic coast. The coveralls, initially Tyvek® 600 but more recently its successor Tyvek® 500 Xpert, are used wherever staff may come into contact with solid airborne particles, hazardous liquid substances and residual radioactive particles. They meet the requirements applicable to Category III chemical protective clothing, Types 5 (particle-tight) and Type 6 (limited splash protection), and to protective clothing against radioactive contamination (EN 1073-2:2002, Class 2/3).
During the clearance (dismantling of plant parts) or clean-up of buildings, staff can come into contact with Kamilit mineral wool insulation, asbestos fibres, mineral and fine particles. Protective garments made from Tyvek® provide an extremely high, abrasion-resistant barrier to airborne particles, even those within the range size of >1 µm in diameter, and so provide reliable protection against contamination by these hazardous substances. The product particle barrier performance by far exceeds the minimum requirements of the Type 5 whole suit inward leakage test. Being single-use protective clothing, contamination is not transferred to other locations; once they have been removed by the wearer, they are immediately sent for disposal. To complement the protection provided by the coveralls, staff wear gloves, full-face or half masks and safety shoes.
Crucial factors in the selection of Tyvek® protective coveralls were their elevated resistance to tearing and tear propagation, the material's good air and water vapour permeability, the low weight of the garment (< 180 g) and its ergonomic design. As Hartmut Timpf, head safety engineer at EWN says: "Our staff sometimes have to work in areas which are difficult to access, so elevated freedom of movement and breathability were decisive criteria when it came to selecting protective garments. DuPont's garments fit like a second skin and do not restrict our staff in carrying out their work. We were also impressed by the quality of the products in terms of their manufacture and material."
Tyvek® protective coveralls are put to many and varied uses at EWN. They are worn when required during dismantling of plant parts from the nuclear power plant. The garments are also used at the various disassembly sites when airborne pollutants are present and in the Central Active Workshop (ZAW) during wet chemical cleaning of disassembled, radioactively contaminated plant parts.