T.O. 33B-1-1
e.
All installations must display suitable Warning signs as given below:
(1)
The interior of the exposure room shall be posted with sufficient ‘‘Danger, High Radiation Area’’
or ‘‘Danger, Very High Radiation Area’’ signs as applicable, so as to be visible from any location.
The interior of a cabinet installation must be posted with an identical sign which must be visible
with the access door open.
(2)
The entrance to the exposure room and cabinet of cabinet type installations housing X-ray
equipment shall be posted with radiation marking signs, either ‘‘Caution, Radiation Area’’,
‘‘Warning, High Radiation Area’’ or ‘‘Warning, Very High Radiation Area’’, as applicable. In
addition, gamma radiography sources and cabinet type installations containing a radioactive
source shall; have a ‘‘Caution, Radioactive materials’’ sign attached to the outside and a label or
sign ‘‘Caution, Produces X-rays when energized’’ (or equivalent) shall be affixed to the X-ray tube
head.
(3)
The area accessible to personnel in which radiation doses could exceed 5 mrem (50 mSv) in any
one hour shall be posted with a ‘‘Caution, Radiation Area’’ sign.
f.
No person, either within the controlled area or in the environs of the installation, is exposed to more
than the radiation protection standard applicable to members of the public unless exposure is
approved in writing, in advance, by the Radiation Safety Officer.
6.9.18.2.3
Operating Instructions.
The following are mandatory operating instructions that must be adhered to in ‘‘enclosed installations’’:
a.
Since the safe operation of an ‘‘enclosed’’ installation is based on the normal operating conditions
specified in the applicable radiation protection survey report, the equipment shall be operated only
within the indicated limits. A copy of the survey report shall be readily available during radiographic
exposures.
b.
When the operating conditions have changed so that there is a probability that the exposure of any
person may be increased, a radiation protection resurvey or evaluation shall be conducted. In case of
doubt, a health physicist or nuclear medicine science officer shall be consulted.
c.
Personnel access to areas where radiography is in progress shall be limited to that which is absolutely
required. All entries into the enclosure must be monitored.
d.
A thorough search for personnel working within the enclosure shall be conducted prior to activating
the source.
e.
The tube head or gamma radiography source, as applicable, should be placed as close as possible to
the center of the room. Whenever possible the beam should be directed toward the f loor, and a piece
of 1/8-inch thick lead plate should be placed on the f loor so as to interrupt the entire primary beam in
order to reduce scatter radiation.
f.
The installation shall be inspected by the radiographers each day the facility is to be used to verify the
proper operation of audible alarms, red visible warning signals, interlocks, delay switches, and other
devices that have a bearing on radiation protection. Interlocks shall be tested by verifying that they
do indeed de-energize the tube head when tripped. Interlocks will be subjected to detailed testing at a
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