Sep 17 Sep Dirty cleaning of powder rooms

Concrete dust, grinders and full suits. Much of the time looks like decommissioning quite a lot of time. The powder room where Risø handled uranium for fuel rods has been thoroughly sanded down on all surfaces.

R The room is foggy with concrete dust, and the grinders make noise through hearing protectors and masks. Here in the former powder room, uranium powder was measured with the utmost care for decades. The uranium was pressed into pieces and rolled into plates, which became fuel rods for Denmark's largest research reactor . Now the entire room is filled with a thick layer of moon dust with traces of wheels and cover cutters.

Uranium powder is fine as icing sugar, and the many years of handling the powder may have spread uranium dust in the room. When fuel production was discontinued in 2000, the room was measured for radioactivity and all surfaces painted over. Our projectants have been prepared for the space to be contaminated or contaminated behind the paint. Therefore, grinding DD 's craftsmen the whole room down and removes the flooring.

The entrance to the powder room is via a double-door lock, where all employees are dressed in boiler suits, masks, gloves and cover shoes before being allowed to enter the dust mists. The ceiling has first been sanded with a remote-controlled machine, which is mounted on rails. After that, it was followed by a giraffe grinder. The dust is sucked up with a special vacuum cleaner and both dust and vacuum cleaner are measured for radioactivity.

It requires a thorough measurement of the entire room before we can be sure that there are no traces of radioactivity left. Therefore, when the powder room is finished, all surfaces are measured by DD 's release function, which consists of specially trained personnel from, inter alia, the radiation and nuclear safety section. The work takes place with a handheld measuring instrument, which we call a CoMo – a contamination monitor.

Fortunately, as work progresses, it has become apparent that there is limited pollution in walls and ceilings. The worktable where Risø's laborers measured uranium powder has been removed and a drain in the floor underneath was contaminated to drill up the entire drain well. The room drain and ventilation must also be cleaned and controlled before the room can be released.