T.O. 33B-1-1
6-143
that under practical conditions of occupancy and use, the dose received by individuals outside the
enclosure will not exceed the annual limit of 100 mrem (1 mSv) per year for members of the
general public
(2)
Shielded Installations: The exposure rate at any accessible location 2 inches (5 cm) from the
outside surface of the enclosure cannot exceed 2 mR in any one hour, and 100 mR per year at the
exterior surface of the facility.
e. All installations must display suitable warning signs as follows:
(1)
The interior of the exposure room shall be posted with sufficient "Caution, High Radiation Area"
(or "Danger, High Radiation Area" or "Danger, Very High Radiation Area") signs so as to be
visible from any location. The interior of a cabinet installation must be posted with an identical
sign that must be visible with the access door open.
(2)
The entrance to the exposure room, or cabinet of cabinet type installations, housing X-ray
equipment shall be coated 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.
f. No person, either within the controlled area or in the environs of "Protective" (“Shielded”) installations
shall receive radiation exposures exceeding the total effective dose equivalent limits for members of the
public.
6.9.18.1.2
Operating Procedures.
The following are mandatory operating procedures that must be adhered to in a “protective” and “shielded”
installations:
a. Protective Installations: No restrictions shall be imposed on the mode of operation (kVp, mA, workload,
or adjacent operations) for protective installations.
b. Shielded Installations: Facilities for shielded operations are designed to limit the exposure at the
exterior surface of facilities to 2 mR in an one hour and 100 mrem per year. Since such designs
incorporate expected workloads, use factors and occupancy factors, these “design” parameters serve as
administrative limits for the operations of shielded installations. 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 in which radiography is in progress is prohibited except as an exception to
policy that shall require MAJCOM Headquarters approval.
d. A thorough search for personnel working within the enclosure shall be conducted prior to activating the
source.
e. The installation shall be inspected by the radiographers each day the facility is to be used to verify the
proper operation of audible red visible warning signals, interlock, delay switches, and other exercises
that have a bearing on radiation protection. Interlocks shall be subject to detailed testing at intervals
not to exceed six months to assure that they function as designed. A bound log, initialed by the
individual making the inspection shall be maintained.
