Contractors were exposed to radioactive dust

Carlisle Crown Court heard that the incident took place on 11 July 2007 during the renovation of a room formerly used to sort and monitor materials contaminated with plutonium. The room was being refurbished to create additional office space at the site.

The room had a patch of concrete floor, which was believed to have been contaminated by a spillage of radioactive material several years earlier. Two contractors were drilling into the floor using a diamond-cutting drill, so that the contaminated area could be removed. They became contaminated with plutonium by the dust that was created by the drilling.

A contamination alarm activated when the dust was created and the work stopped immediately. One of the workers had substantial dust on his PVC suit, and inhaled some of the toxic particles when he removed his respirator while undressing. Both contractors were found to have received a significant radiation dose, but this fell beneath the annual dose limits and had no immediate impact on their health.

HSE superintending nuclear inspector, Mark Bassett, noted that the company should have erected a ventilation tent, and ensured that contractors wore pressurised suits rather. He said: “Although the radiation doses in this case were below the statutory dose limits, they could potentially have been higher – they should have been zero.

“The incident highlights the importance of Sellafield Ltd following its own arrangements for protecting workers, when undertaking potentially hazardous work with the risk of exposure to radiation. Sellafield should have properly assessed those risks, and then appropriately planned, organised, and carried out the work.”

Sellafield appeared in court on 4 December and pleaded guilty to breaching s3 of the HSWA 1974. The company was fined £75,000 and ordered to pay full costs of £26,100.

A Sellafield spokesperson said: “This incident happened more than a year before Nuclear Management Partners (NMP) took over control of Sellafield Ltd (in November 2008), bringing with them a wealth of experience and expertise from around the globe. Since arriving on site, the new management team has introduced a range of initiatives aimed at improving safety and performance.



“The entire management team of Sellafield is dedicated to reducing the risk of incidents like this happening in the future. The site is made up of many old facilities with lots of challenging plants. We are therefore applying rigorous common operational standards across all sites and we are dedicated to continuous improvement.”

Inspector Bassett concluded: “We are satisfied that Sellafield is taking the appropriate measures to improve both its arrangements and to ensure they are carried out properly. We will continue to monitor closely to ensure that these are implemented.”