QSA Global, Inc.
40 North Avenue Burlington, MA 01803
888.272.2242
781.272.2000
qsa-global.com
Operations Manual
MAN-038 March 2019
Page 94 of 100
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 gamma-ray source projector 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 Becquerels and Curies that cannot be exceeded, of a sealed source
specified by radionuclide by the manufacturer when contained within a radiographic gamma-ray source
projector or a transport container.
Plunger lock
A mechanical device with a key used to lock or unlock the radiographic gamma-ray source projector or
transport container.
Projection sheath
A flexible or rigid tube for guiding the source assembly from the radiographic gamma-ray source projector
to the working position, having the necessary connections for attachment to the radiographic gamma-ray
source projector 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 gamma-ray source projector. 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 gamma-ray source projector and source assembly, when the sealed source
assembly is fully shielded and restricted to this position within the radiographic gamma-ray source
projector. The SENTINEL SENTRY 330 and SENTINEL SENTRY 110 are equipped with automatic
securing mechanisms that are actuated whenever the source assembly is fully retracted into the gamma-
ray source projector’s fully shielded position.
Note: When in the secured position during radiographic operations, the radiographic gamma-ray source
projector may be unlocked.
