United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 82-33: Control of Radiation Levels in Unrestricted Areas Adjacent to Brachytherapy Patients

                                                                 SSINS NO.: 
                                                                 IN 82-33 

                               UNITED STATES 
                       NUCLEAR REGULATORY COMMISSION 
                    OFFICE OF INSPECTION AND ENFORCEMENT 
                           WASHINGTON, D.C. 20555 

                              August 20, 1982 

Information Notice No. 82-33:   CONTROL OF RADIATION LEVELS IN 
                                   UNRESTRICTED AREAS ADJACENT TO 
                                   BRACHYTHERAPY PATIENTS 

Addressees: 

All Medical Institutions. 

Purpose: 

During the course of several inspections NRC inspectors have found radiation
levels exceeding regulatory limits in unrestricted areas adjacent to brachy 
therapy patients. This notice discusses the applicable regulatory limits and
associated requirements. It is expected that recipients of this Information 
Notice will review the information for applicability to their facilities. No
specific response to this notice is required. 

Discussion: 

Radiation levels in unrestricted areas may not exceed the limits as 
specified in 10 CFR 20.105(b)(1) and (2) unless the licensee has been 
granted an exemption by demonstrating at the time of applying for a license 
or amendment that the requirements of paragraph 20.105(a) will be met. This 
exemption must be stated as a specific condition of the license. 

Treatment of patients with brachytherapy sources may result in a situation 
where the public may be exposed to unnecessary radiation. Insufficient 
distance between the restricted and unrestricted areas and a lack of 
shielding material in brachytherapy rooms has, in some cases, resulted in 
the existence of levels of radiation greater than the permissible limits 
specified in 10 CFR 20.105(b)(1) and (2). "Adjacent areas" may include 
adjacent rooms and hallways as well as areas on floors above and below the 
brachytherapy patient's room,. 

The regulations require that, unless an exemption under paragraph 20.105(a) 
has been granted, radiation levels may not exist in unrestricted areas so 
that, if an individual were continuously present in the area, it could 
result in that individual receiving a dose in-excess of 2 millirem in any 
one hour or 100 millirem in any seven consecutive days. It is important to 
note that compliance must be established with both paragraph 20.105(b)(1) 
and (2). As an example, if a hospital treated a sufficient number of 
brachytherapy patients to maintain continuous occupancy in one room and 
radiation levels in adjacent unrestricted areas were greater than 0.6 
millirem/hour, the facility would be in violation of paragraph 20.105(b)(2). 
Specifically, a situation would exist where an individual who continuously 
occupied the unrestricted area might receive more than 100 millirems in 
seven consecutive days. 

8204210411  
.

                                                           IN 82-33  
                                                           August 20, 1982 
                                                           Page 2 of 2 

In establishing compliance with paragraph 20.105(b)(1) and (2), it is 
necessary to conduct a survey as required by paragraphs 20.201(a) and (b). 
An evaluation of the radiation hazard must be made that, if appropriate, 
would include measurements of the levels of radiation. In the event that 
radiation levels greater than permissible levels are encountered, action 
must be taken to reduce the level. Action might include increasing the 
distance between the patient and the unrestricted area or the use of 
portable shields. After employing such methods, a survey must again be 
performed to assure that radiation levels in adjacent areas are below the 
permissible limits. Records of these surveys must be maintained as required 
by paragraph 20.401(b). 

No written response to this information notice is required. If you need 
additional information regarding this subject, you should contact the 
Regional Administrator of the appropriate regional office. 



                              L. I. Cobb, Director 
                              Division of Fuel Facilities, Materials 
                                and Safeguards, IE 

Technical Contact:  C. Yaczko 
                    301-492-9748 

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