GE Discovery NM/CT 670 - Scan Room Shielding

Special Construction Requirements 3.1 Radiation Protection and Shielding Requirements
3.1.2 Scan Room Shielding
Discovery NM/CT 670 – Standard Integration Instructions
5483063-1EN, Rev.2, ©2015 GE Healthcare 3-3
3.1.2 Scan Room Shielding
Shielding of the Scan Room includes walls, lead-shielded glass, lead shields, etc. and must be
sufficient to protect staff from unnecessary exposure to radiation. The shielding requirements must
be determined by a qualified radiological health physicist, taking into consideration:
 Local regulatory requirements
 Facility policy
 CT scatter radiation levels within the scanning room (see Figure 3-1, p.3-5)
 Patient location and level of radiation from patients after intake of radionuclides
 Equipment placement
 Materials used for construction of walls, floors, ceiling, doors, and windows
 Weekly projected work-loads (# patient/day technique (kvp*ma))
 Access to areas surrounding the Scan Room
 Equipment in areas surrounding the Scan Room (for example: film developer, film storage)
 Protection of operator room, included leaded window, walls and door
Figure 3-1, p.3-5 depicts measurable CT radiation levels within the scanning room while scanning
a 32 cm CTDI phantom (body) and a 20 cm water phantom (head), with the technique shown.
The mAs, kV and aperture scaling factors shown in Table 3-1, p.3-4 can be used to adjust exposure
levels to the scan technique used at the site.