Medical Shielding

Cerberus Nuclear has provided shield testing and substantiation services for the Brighton 3TS project at the Royal Sussex County Hospital. This work was in support of the installation of lead shielding in various theatres, totalling 40 rooms across five levels.
The shielding took the form of various codes of lead plasterboard, with the PET rooms requiring thicker, lead chevron block shielding. Cerberus Nuclear provided Radiological Protection Advisor (RPA) advice and inspection of the installation of this shielding to ensure that it fulfilled the design intent; also producing memos to record the details of these inspections.
In addition to this, Cerberus Nuclear provided substantiation of the shielding installation using a sealed source (for the lead plasterboard rooms) and a portable X-ray betatron (for the lead chevron blocks). Cerberus Nuclear have provided all relevant documentation for this work, including conventional and radiological risk assessments, local rules, written arrangements, method statements, and sampling plans. This has included performing simple, MicroShield and hand calculations to determine dose rates through relevant lead thicknesses for the different source terms.
 

To assist with the installation of a new biplane X-ray imaging machine, Cerberus Nuclear used Monte Carlo and hand calculation methods to determine the amount of shielding required in the catheterization laboratory to reduce external doses below a given threshold.

The shielding material was chosen to be varied codes of lead lining the walls of the laboratory; the height of which was investigated to determine whether an upper gap may be left to allow ducts and sockets to penetrate the wall. Monte Carlo scatter calculations were performed to produce a dataset of resultant dose values and contour plots, allowing X-ray penetration and scatter externally and into the control room to be reduced below the annual dose limits.

Additionally, the placement of the X-ray imaging system was analysed for all locations within the room through use of hand calculation methods and code scripting. These calculations allowed the system to be placed in the optimal position for reducing doses and hence minimizing the required shielding.