The DTU Department of Health Technology on DTU Risø Campus in Roskilde possesses an MDS Nordion Gamma cell 220 Irradiator S/N 220R. It serves as the national standard for high-dose dosimetry. The Gamma cell was initially installed in 2007 and it was resourced in 2014. The existing loading of the Gamma cell consists of 20 type C-198 sources of total activity 15 kCi (555 TBq) in April 2014. The number of free source positions in the source cage is 28. DTU wants to re-source the Gamma cell to achieve a total activity of 15 kCi (555 TBq) of Co-60. This may be achieved by the addition, or replacement, of sources in existing Gamma cell, or by the supply of an exchange Gamma cell with new sources.