IE Circular No. 80-06, Control and Accountability Systems for Implant Therapy Sources
SSINS No.: 6830
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
WASHINGTON, D.C. 20555
April 14, 1980
IE Circular No. 80-06
CONTROL AND ACCOUNTABILITY SYSTEMS FOR IMPLANT THERAPY SOURCES
Several incidents have been reported to the Nuclear Regulatory Commission
(NRC) during the past two years regarding inadequate control of sealed
radiation therapy sources which contain NRC-licensed byproduct materials.
These incidents were the result of poor licensee management and failure to
comply with the NRC Regulations. All individuals in your institution
involved in the use of such sealed sources, as well as the management,
should review the contents of this Circular.
DESCRIPTION OF SEVERAL INCIDENTS REPORTED TO THE NRC:
1.(a) 20 ribbons containing 135 Ir-192 seeds were implanted in a patient.
The radiation therapist removed twelve ribbons in the patient's room
but did not count the seeds. The removed seeds were left in a lead
container in the patient's room until two days later when the
remaining seeds were removed. When the seeds from both removals were
counted, it was determined that some seeds were missing. Subsequent
surveys have not found all of the missing seeds.
(b) 182 Ir-192 seeds were removed from a patient and placed in a lead
container which was located on a hospital cart. A ten seed ribbon
later became displaced from the container, fell to the floor and was
swept up by a vacuum cleaner. One seed was ripped out of the ribbon
by a rotating brush of the vacuum cleaner and became lodged in the
mechanism. The remaining nine seeds were found intact in the ribbon
outside of the hospital near where the contents of the vacuum bag are
The above licensees were in violation of 10 CFR 20.207(a) and (b)
which require that licensed material stored in an unrestricted area
be secured from unauthorized removal from the place of storage, and
if not in storage, be under the constant surveillance and immediate
control of the licensee.
2. A patient had twelve Ir-192 seeds implanted but only eight removed at
the desired time. The remaining four iridium seeds were noticed
missing about three months later. Licensee follow-up revealed that
these seeds were still in the patient.
This is in violation of 10 CFR Part 35.14 (vii) which requires that
implant patients remain hospitalized until a source count and a
radiation survey confirm that all implants have been removed.
IE Circular No. 80-06 April 14, 1980
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3. An applicator containing two 79 mCi Cs-137 sources was removed from a
patient and returned to the storage room, but not immediately
dismantled. A routine inventory two weeks later revealed that one of
the two sources was missing. The hospital was unable to either
locate the missing source or determine who had disassembled the
4. One hospital reported that a 40 mCi Cs-137 uterine implant was
dislodged from a patient and only after an extensive search was it
found in a laundry room floor drain trench.
NOTICE TO LICENSEES
NRC recommends that the following actions be considered by each licensee
authorized to use sealed sources in topical, interstitial or intracavitary
treatment of cancer. These recommended actions may already be a part of
your program and may be conditions of your license. If you change any
procedures which are conditions of your license, you must notify the
Radioisotope Licensing Branch of NRC so that your license may be amended.
Review the adequacy of your procedures for the use and control of sealed
therapy sources. Such procedures should include:
a. Written instructions covering all phases of use and control. These
instructions should be readily available to all individuals involved
with the use of sealed therapy sources. In addition all users should
be trained in the implementation of these procedures.
b. Establishment and maintenance of a source inventory log book. This
should contain a running inventory of all sources, based on physical
counting, as they are received from the supplier, removed from
storage for use in patients, and placed back into storage. The
inventory records should clearly indicate the total number of sources
in storage at all times.
c. Verification, by physical counting, the number of sources used in a
treatment before they are implanted and immediately after their
removal from a patient.
d. Written instructions for survey of patients by a qualified person
using proper radiation detection instruments. This radiation survey
should be performed as soon as practicable after the source removal,
but in any case before the patient is released from the hospital. In
addition, the patient's room, all linen, clothing and other materials
should be surveyed prior to removal from the room and upon
termination of treatment to determine if any sources may have become
e. Requirement for frequent management audit of source inventory records
for completeness and accuracy.
No written response to this Circular is required. If you require additional
information regarding this matter, contact the Fuel Facility and Materials
Safety Branch of the appropriate NRC Regional Office.
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