SIGMA projetor - Manual (Page 68)

DEFINITIONS AND TERMS
6.2
Exposure head
Device which locates the sealed source included in the source assembly, in the selected working position
and prevents the source assembly from projecting out of the projection sheath. Also known as: source
stop, end stop, snout and head-hose.
Locked position
Describes the condition when the lock on a radiographic exposure device or transport container is fully
engaged to lock the source assembly in place and the key is removed from the lock. This condition
prevents unauthorized personnel access to the sealed source assembly locked within the device.
Maximum rating
The maximum activity expressed in bequerels and curies that cannot be exceeded, of a sealed source
specified by radionuclide by the manufacturer when contained within a radiographic exposure device or a
transport container.
Plunger lock
A mechanical device with a key used to lock or unlock the radiographic exposure device or transport
container.
Projection sheath
A flexible or rigid tube for guiding the source assembly from the radiographic exposure device to the
working position, having the necessary connections for attachment to the radiographic exposure device
and the exposure head or including the exposure head itself. The projection sheaths also provide
protection of the source assembly and attached control cable from water, dirt, sand and other foreign
materials usually present at radiography environments. Also known as: source guide tubes, guide tubes,
source tubes, head-hoses. Examples of rigid projection sheaths include j-tubes, probes, jet engine
probes.
Remote control
The mechanical device that enables the source assembly to and from a working position by operation
from a distance away from the radiographic exposure device. The remote control includes the control
crank mechanism (normally a hand-crank), and where applicable, also the control cable, the control cable
sheath and the necessary connections and attachments. See additional description under ‘control crank’.
Reserve sheath
Remote control sheath (conduit) containing the length of control cable, necessary for the projection of the
source assembly.
Sealed source
Radioactive source sealed in a capsule or having a bonded cover, the capsule or cover being strong
enough to prevent contact with and dispersion of the radioactive material under the conditions of use and
wear for which it was designed. Commonly referred to as: the ‘source’ or the ‘pill’.
Secured position (shielded position)
Condition of the radiographic exposure device and source assembly, when the sealed source is fully
shielded and restricted to this position within the radiographic exposure device.
Note:
When in the secured position during radiographic operations, the radiographic exposure device
may be unlocked.
Simulated source
A sealed source whose structure is such as that of the sealed radioactive source, but not containing any
radioactive material. Also known as: mock source, dummy source, phantom source, dummy pill.