Low Cost Alternative to Lead Glass Shielding in PET/CT Control/Scanner Room Window

Abstract

The aim of this work is to propose a reasonably priced alternative to expensive lead glass used in PET/CT windows connecting the control room and the scanner room. These windows can be extremely useful to detect if the patient needs quickly to be assisted, for anesthesia surveillance when needed, among several other purposes and is mandatory to exist in these facilities. The window must provide also radiation protection to the worker inside the control room. One way to accomplish this task is to use lead glass. However, lead glass is expensive and is usually manufactured as predetermined lead equivalent thicknesses (frequently 2 mm or more). It is also designed to be lead equivalent with nominal thicknesses specified for radiology energy ranges. Depending on the distances involved and on the workload, since the photon energy irradiating from PET patients is significantly higher (511 keV) than other nuclear medicine and radiology procedures, it is usually necessary to protect the professionally exposed worker with a high thickness of lead or lead equivalent glass. For a big area window, a lead glass plate can be quite expensive. In this work it is presented a less expensive solution using common glass with thickness higher than 15 cm. Calculations are presented for typical situations and workloads, assuring protection both from PET and CT.