Information Notice No. 94-09: Release of Patients with Residual Radioactivity from Medical Treatment and Control of Areas due to Presence of Patients Containing Radioactivity Following Implementation of Revised 10 CFR Part 20

                                 UNITED STATES
                         NUCLEAR REGULATORY COMMISSION
                            WASHINGTON, D.C. 20555

                               February 3, 1994

Information Notice No. 94-09:  RELEASE OF PATIENTS WITH RESIDUAL
                                   RADIOACTIVITY FROM MEDICAL TREATMENT AND
                                   CONTROL OF AREAS DUE TO PRESENCE OF
                                   IMPLEMENTATION OF REVISED 10 CFR PART 20


All U.S. Nuclear Regulatory Commission medical licensees.


NRC is issuing this information notice to notify addressees of the
Commission's intent for release of patients pursuant to 10 CFR 35.75.  It is
expected that licensees will review this information for applicability to
their operations and distribute it to appropriate staff.  The information
contained in this notice does not include new NRC requirements; therefore, no
specific action nor written response is required.

Description of Circumstances

NRC's current patient release criteria, adopted in 1986, are contained in 10
CFR 35.75, "Release of patients containing radiopharmaceuticals or permanent
implants."  Specifically, this section states:

  (a)  A licensee may not authorize release from confinement for medical care
       any patient administered a radiopharmaceutical until either:

       (1)  The measured dose rate from the patient is less than 5
            millirems (mrem) per hour at a distance of one meter; or

       (2)  The activity in the patient is less than 30 millicuries

  (b)  A licensee may not authorize the release from confinement for medical
       care of any patient administered a permanent implant until the measured
       dose rate is less than 5 millirems per hour at a distance of one meter.

In the discussion of the proposed 10 CFR 35.75 in 1985, the Commission stated
that the proposed limits (30 millicuries (mCi) of activity or 6 milliroentgens
per hour dose rate at 1 meter, based on the exposure rate from 30 mCi iodine-
131), provided an "... adequate measure of safety for the general public, and
that further reductions in public exposure are not reasonably achievable


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                                                            February 3, 1994
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considering the cost and potential for detrimental effect from an
unnecessarily long hospital confinement."  Subsequently, the 1986 Statements
of Consideration for the revision to 10 CFR Part 35 discuss that the release
criteria, specified in 10 CFR 35.75 (30 mCi of residual activity or
5 millirems per hour (mrem/hr) dose rate at 1 meter) are based, in part, on
the considerations addressed in NCRP Report No. 37, "Precautions in the
Management of Patients who Have Received Therapeutic Amounts of
Radionuclides."  Again, the Commission reiterated that the release limit
provided an adequate measure of public health and safety.

On May 21, 1991, NRC published a final rule (56 FR 23360) that amended 10 CFR
Part 20, "Standards for Protection Against Radiation."  Licensees are required
to implement the revised Part 20 by January 1, 1994.  10 CFR 20.1301(a)
requires, in part, that a licensee conduct operations so that:  1) the total
effective dose equivalent to any individual member of the public from licensed
activities does not exceed 1 millisievert (mSv) (0.1 rem) in a year; and
2) the dose in any unrestricted area from external sources does not exceed
0.02 mSv (0.002 rem) in any 1 hour.  There has been some concern, in the
medical community, that a licensee, assuming compliance with 10 CFR 35.75 and
other applicable Part 35 requirements, in releasing, from confinement, a
patient containing byproduct material, could be in violation of the revised
Part 20, if the dose limits specified in 10 CFR 20.1301(a) are exceeded as a
result of radiation emitted from a patient undergoing a medical procedure.


The adoption of 10 CFR 35.75 in 1986 was based on an independent NRC public
health and safety judgment specific to patient release, and was neither tied
to, nor designed to implement, the more general Part 20 dose limits that were
later revised in 1990.  When Part 20 was revised, there was no discussion in
the "Statements of Consideration" on whether or how the provisions of 10 CFR
20.1301 would apply to the release of patients.  Since a general and a
specific regulation of the Commission both address the same subject, the
staff, in consultation with the Commission, has taken an interim position that
the more specific regulation prevails in this case, pending action to formally
resolve the issue in response to pending rulemaking petitions.

Therefore, licensees should continue past practices regarding radiation
exposure to individual members of the public from radioactive materials
administered to patients, whether inpatients or outpatients.  The provisions
of 10 CFR 20.1301(a) should not be applied to radiation received by a member
of the general public from patients released from confinement in accordance
with 10 CFR 35.75 and other applicable requirements in Part 35.  Furthermore,
if a patient is not required to be confined, pursuant to 10 CFR 35.75,
licensees are not required to limit the radiation dose to members of the
public (e.g., visitor in a waiting room) from a patient to 0.02 mSv (2 mrem)
in any one hour.  Patient waiting rooms or hospital rooms need only be
controlled for those patients not meeting the release criteria in 10 CFR


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This information notice requires no specific action nor written response.  If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate regional office.

                                          /S/'D BY CJPAPERIELLO

                                          Carl J. Paperiello, Director
                                          Division of Industrial and
                                            Medical Nuclear Safety
                                          Office of Nuclear Material
                                            Safety and Safeguards

Technical contacts:     Patricia K. Holahan, NMSS
                        (301) 504-2694

                        Catherine T. Haney, NMSS
                        (301) 504-2628

1.  List of Recently Issued NMSS Information Notices
2.  List of Recently Issued NRC Information Notices

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