ML20045A730
| ML20045A730 | |
| Person / Time | |
|---|---|
| Issue date: | 06/08/1993 |
| From: | Congel F Office of Nuclear Reactor Regulation |
| To: | Lieberman J, Miller V, Treby S NRC OFFICE OF INVESTIGATIONS (OI), NRC OFFICE OF STATE PROGRAMS (OSP), NRC OFFICE OF THE GENERAL COUNSEL (OGC) |
| References | |
| NUDOCS 9306110303 | |
| Download: ML20045A730 (32) | |
Text
7 JUN 0 81993 MEMORANDUM FOR:
Vandy L. Miller, Assistant Director, OSP Kenneth E. Raglin, Director, TTC James Lieberman, Director, 01 Stuart A. Treby, 0GC Joanna M. Becker, OGC Seymour H. Weiss, Director, ONDB, NRR Richard W. Cooper, II, Director, DRSS, Region I J. Philip Stohr, Director, DRSS, Region II Charles E. Norelius, Director, DRSS, Region III L. Joseph Callan, Director, DRSS, Region IV Ross A. Scarano, Director, DRSS, Region V FROM:
Frank J. Congel, Director Division of Radiation Safety and Safeguards Office of Nuclear Reactor Regulation
SUBJECT:
FIFTH SET OF QUESTIONS AND ANSWERS ON NEW PART 20 A fifth set of questions and answers on the major revision of 10 CFR Part 20 (new Part 20) is enclosed for your information (Enclosure 1). A draft of these questions and answers was provided earlier for your review. is a correction to the answer to question 26(a), in the fourth set of questions and answers.
This correction makes the answer to question 26(a) consistent with the answer to question 411 in the enclosed fifth set of questions and answers (under the section for 10 CFR 19.12).
These questions and answers are being made publicly available.
Urigifiallignsd by Frank J. Congel Frank J. Congel, Director Division of Radiation Safety and Safeguards Office of Nuclear Reactor Regulation
Contact:
John Buchanan, NRR pgg o f
(301) 504-3184
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Enclosures:
As stated DISLRIBUTION:
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b ENCLOSURE 1 I
FIFTH SET OF QUESTIONS AND ANSWERS ON THE NEW PART 20 following are questions and answers concerning the new 10 CFR Part 20 (10 CFR Part 20 Sections 20.1001 - 20.2401) and its implementation. These questions and answers have been compiled primarily for use in training NRC regional inspection staff members, but they are being made publicly available for information of interested organizations and to encourage communications between the public and the NRC staff concerning this new rule. Additional questions and answers are being compiled and will be made publicly available at a later date.
The questions included here were provided by individuals and organization outside the NRC and by NRC staff members. Answers to these questions have been prepared by, and reviewed by NRC staff members in the NRC Offices of Nuclear Reactnr Regulation, Nuclear Material Safety and Safeguards,' Nuclear Regulatory Research, Office of State Programs, and the five NRC Regional Offices.
The questions and answers also have been reviewed by an attorney in the NRC Office of the General Counsel.
The answers to questions do not constitute official legal interpretations, which can only be provided by the General Counsel, and they do not reflect official NRC policy as approved by the Commission. The answers do reflect NRC staff decisions and technical opinions on specific aspects of regulatory requirements.
Additional information about the questions and answers follows:
o Questions and answers are arranged in the order of appearance in Part 20 of the section of Part 20 to which the question appears to be most closely related.
Questions on Part 20 itself are followed by related questions concerning 10 CFR Part 19, reactor technical specifications, and regulatory guides, o
The questions are not in numerical order.
The number assigned to each question is merely a unique identification number. This identification number has no relationship to the subject of the question.
o Unless otherwise indicated in an answer, a reference to a Federal Register volume and page number (e.g., 56 FR 23377) refers to a page 4
number in the May 21, 1991 edition of the Federal Reaister, which contained the new Part 20 and related information, on pages 23360-23474.
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o The first four sets of questions and answers are identified by their dates of issuance and their NRC accession numbers in the following table.
The accession numbers can be used by the NRC staff to retrieve these documents from the NUDOCS system and by members of the public to obtain the documents from the NRC Public Document Room.
Set Date Accession No.
First 12/6/91 9112190258 Second 4/17/92 9205010117 Third 7/23/92 9207300261 Fourth 9/14/92 9209230012 1
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L FIFTH SET OF QUESTIONS AND ANSWERS ON NEW PART 20 10 CFR 20.1001 Purpose QUESTION 407:
(a) Does Part 20 apply to emergency response personnel such as city fire fighters?
(b) If Part 20 does apply, would the radiation dose received by the workers be considered to be an occupational dose or a public dose?
AN1W18:
(a) No. As stated in 10 CFR 20.1001, " Purpose," Part 20 applies to activities conducted under licenses issued by the NRC.
Emergency response activities such as fire fighting by employees of a city fire department are not conducted under a license issued by the NRC (even when the fire being fought is in a facility of an NRC licensee).
Furthermore, as stated in 10 CFR 21.1001, nothing in Part 20 shall be construed as limiting actions to protect health and safety.
Thus, Part 20 does not apply to emergency response activities and workers such as fire fighting by employees of a city fire department.
For NRC licensees, it is the Commission's intent that the regulations-be observed to the extent practicable during emergencies, but that conformance with the regulations should not hinder any actions that are necessary to protect public health and safety such as lifesaving or maintaining confinement of radioactive materials (56 FR 23365). Also, for nuclear power reactor licensees, a different part of the regulations,10 CFR Part 50, includes a requirement, in 10 CFR 50.47(b)(11), that the offsite emergency response plans must include means for controlling radiological exposure of emergency workers in an emergency.
(
Reference:
10 CFR 20.1001) 10 CFR 20.1003 Definitions OUESTIOJ 149:
10 CFR 20.1003 defines the shallow-dose equivalent as the dose equivalent at a tissue depth of 0.007 cm. (a) Does this mean that the dose to the skin of the whole body is the sum of the non-penetrating dose equivalent i
(beta and low energy photons) and the deep dose equivalent?
(b) Is it proper to calculate the extremity dose by summing the dose equivalent measured on an extremity dosimeter (which may only be worn for part of the monitoring period) with the deep dose equivalent?
ANSWER: General response:
10 CFR 20.1502 requires monitoring of external dose for individuals who are likely to receive, in a year, a dose in excess of 10% of the applicable limits.
Requirements to measure / assess the dose equivalent at depths of 0.007, 0.3, and I cm exist under old Part 20 as well as the new Part 20.
In old Part 20, these requirements are included in the i
instructions for item 5 of NRC Form 5.
In the new Part 20, these requirements i
are in Part 20 itself, together with new dose limits and special names, in the definitions for the dose equivalents at these three depths. The only explicit requirements concerning the precision and accuracy of personnel dosimetry are the NVLAP accreditation requirements, which are the same in old Part 20 [10 CFR 20.202(c)] and new Part 20 [10 CFR 20.1501(c)]. Methods that have been acceptable for measuring / assessing dose equivalent at these three depths in the past should continue to be acceptable in the future.
Answers to the specific questions are as follows:
(a) No. The " dose to the skin of the whole body" is the shallow dose equivalent.
The phallow-dose equivalent is the dose equivalent at a depth of 0.007 cm (7 mg/cm ) from all types of radiation, whether " penetrating" (such as gamma rays and neutrons) or "non-penetrating" (such as weak beta radiation and lower energy x-rays).
(b)
No, not in general. The question does not make it clear whether or not the dose summing is for dose during the same time period.
It is never proper to calculate an extremity dose (shallow-dose equivalent) for a particular time period by adding a deep dose equivalent to the shallow-dose equivalent.
If the question refers to a monitoring period during which an extremity dosimeter (measuring shallow-dose equi. valent) was used only part of the time, but during which a whole-body dosimeter was used all of the time, the answer depends on the circumstances of the individual's exposure.
It would be acceptable to assume, for the times during which the extremity dosimeter is not used, that the extremity dose (shallow-dose equivalent) is equal to the shallow-dose equivalent measured by the whole-body dosimeter.
If only the deep-dose equivalent is measured by the whole-body dosimeter, it would be acceptable to assume, for times during which the extremity dosimeter is not used, that the extremity dose is equal to the deep-dose equivalent (measured by the whole-body dosimeter) if it can be shown that types and levels of radiation to which the extremity was exposed would not have resulted in a significantly higher shallow-dose equivalent to the extremity than the deep dose equivalent to the whole body.
(
Reference:
OVEST10N 150:
10 CFR 20.1003 defines tissue monitoring depths of 0.007, 0.3, and I cm for shallow, eye, and deep-dose, respectively; (a) Is it important to measure at (or extrapolate the measurements to) these exact depths?
(b) could the eye and deep-dose both be determined at 0.3 cm?
i ANSWER:
See the " general response" in the answer to (fuestion 149.
t (a) As under the old Part 20, it is important to measure (or to extrapolate measurements to, or otherwise assess the dose equivalent) at a reasonable approximation of these depths.
(b) No.
The deep-dose equivalent is, by definition, the dose equivalent at a depth of I cm, not 0.3 cm. However, the dose at 0.3 cm (eye dose) would i
usually be a conservative approximation (overestimate) of the dose at I cm (deep-dose).
(
References:
?
d OVESTION 80: The revised Part 20 (520.1003) provides definitions of " member of the public," "public dose," and " occupational-dose." These definitions are not consistent with the definition of " member (s) of the public" defined (for nuclear power plants) in Generic Letter 89-01, Supplement 1. (NUREGs 1301 and 1302).
Consider that typically, one would expect any individual entering the
" restricted area" would be considered to be occupationally exposed and not classified as a " member of the public." All individuals, including utility employees, their contractors, and delivery people, outside the " restricted
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area," in the " controlled area," would be considered as " members of the public." The only exception is where a utility employee or its contractor are performing work in a portion of the " controlled area" where public access has i
been restricted due to radiological exposure considerations. This concept is consistent with the revised rule.
l t
Will the definitions of " member (s) of the public" in Generic Letter 89-01, Supplement 1 (NUREGs 1301 and 1302) be changed to be consistent with the definition of " member of the public" in the new Part 20?
ANSWER:
Yes. The NUREGs themselves will not be changed; however, in a forthcoming Generic Letter on model Technical Specifications that incorporate provisions of new Part 20, the definition of " member (s) of the public" will be changed to be consistent with new Part 20. See Question 26 and answer in the fourth set of questions and answers for clarification of the definition of
" occupational dose."
(
References:
10 CFR 20.1003, NUREG-1301, NUREG-1302).
QUESTION 119:
Is it permissible under 10 CFR Part 20 for a licensee to have a controlled area that is controlled for purposes of radiation protection but that is not a restricted area?
ANSWER:
No.
By definition, in Part 20, a " restricted area means an area, access to which is limited by the licensee for the purpose of protecting individuals against undue risks from exposure to radiation and radioactive i
materials." As stated in the answer to Question 26(a) under the heading
" Controlled Area":
...an area that satisfies both the definition of a restricted area and the definition of a controlled area is considered to be a restricted area for purposes of compliance with Part 20." (
Reference:
10 CFR 20.1003) 10 CFR 20.1101 Radiation Protection Proarams RUESTION 133:
10 CFR 20.1101(b) requires licensees to use, to the extent
" practicable," procedures and engineering controls based upon sound radiation protection principles to achieve doses that are ALARA.
The ALARA concept emphasizes dose-reduction techniques that are reasonable considering costs.
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However, " practicable" may imply something that has been proposed and seems feasible but has not been actually tested in use. " Practical" is more consistent with the ALARA concept because " practical" implies " sensible",
" involving good judgement" and " proven success in meeting the demands made by actual living or use."
In making decisions about ALARA procedures and engineering controls, will licensees be permitted to interpret " practicable" as " practical"?
ANSWER; In the context of this regulation, the word " practicable does not have the connotations attributed to it in the question.
10 CFR 20.1003 states that "ALARA...means making every reasonable effort to maintain exposures to radiation as far below the dose limits in this part as is practical..."
(emphasis added). The discussion of 10 CFR 20.1101(b) in the preamble to new
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Part 20 (56 FR 23367) includes the following statement:
" Compliance with this requirement [10 CFR 20.1101(b)] will be judged on whether the licensee has incorporated measures to track and, if necessary, to reduce exposures and not whether exposures and doses represent an absolute minimum or whether the licensee has used all possible methods to reduce exposures." Thus the use of i
the word " practicable" in 10 CFR 20.1101(b) does not imply procedures and engineering controls that are unproven.
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Reference:
OVEST10N 380: Nuclear power plant licensees are required to meet the quality assurance criteria in 10 CFR Part 50 Appendix B.
Regulatory Guide 1.33 describes a program acceptable to the NRC staff to demonstrate compliance with 10 CFR 50 Appendix B requirements and includes guidance regarding the documentation, use of procedures and periodic review of radiation protection i
programs. Does commitment to and conformance with 10 CFR Part 50 Appendix B and Regulatory Guide 1.33 fully meet the requirements of 20.1101(a) and (c)?
Note: The answer to Question 118 provided previously did not clarify if additional requirements are imposed on nuclear power plants by 20.1101(a) and (c) that are new or different from the previously applicable requirements.
ANSWER: No.
See related question 134 and answer in the fourth set of questions and answers.
10 CFR Part 50 Appendix B and 10 CFR 20.1101(a) and (c) are different requirements.
10 CFR Part 50 Appendix B establishes quality assurance requirements for the operations of nuclear power plant safety-related structures systems and components.
10 CFR 20.1101(a) requires each license to develop, document, and implement a radiation protection program commensurate with the scope and extent of licensed activities and sufficient to ensure compliance with the provisions of Part 20.
10 CFR 20.1101(c) requires periodic reviews of that radiation protection program. Although for nuclear power plants, there is some overlap between the requirements of 10 CFR 50 Appendix B and the requirements of 10 CFR 20.1101(a) and (c), they clearly are different requirements.
For example, some aspects of the radiation protection program established pursuant to 10 CFR 20.1101 (a) may not be considered " safety related" within the meaning of this term in 10 CFR 50 Appendix B.
The reference to 10 CFR Part 50 Appendix B in the answer to
i
- Question 118 (in the third set of questions and answers on new Part 20) was provided in the context of a discussion of quality assurance audits and was t
not an indication that " commitment to and conformance with Appendix B and Regulatory Guide 1.33 fully meet the requirements of 920.1101(a) and (c)."
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References:
DUESTION 381:
(a) For nuclear power facilities does conformance with Regulatory Guides 8.8 and 8.10 fully meet the requirements of 20.1101(b) regarding ALARA programs?
(b) If not, does the NRC plan to update these Regulatory guides to conform to new requirements?
ANSWER: No, to both questions. (a) Regulatory Guide 8.8 Rev. 3 is now (in 1993) 15 years old, the second proposed revision to this guide is now 11 years old, and Regulatory Guide 8.10 is 16 years old. These guides do not adequately cover all the means that the nuclear power industry.has developed and shown to be practical and cost-effective for maintaining occupational doses ALARL For example, these guides do not recognize the importance of water chemistry controls and radiation source and field controls for maintaining doses that are ALARA.
(b) The NRC staff has not yet established a schedule for updating these guides. The staff did issue Draft Regulatory Guide DG-8004, " Radiation Protection Programs for Nuclear Power Plants," to i
provide guidance on compliance with 10 CFR 20.1101, " Radiation Protection Programs," including guidance on the ALARA requirements of 10 CFR 20.1101(b).
However, representatives of the nuclear power industry stated that this guide was not needed and it has been withdrawn.
(
Reference:
10 CFR 20.1204 Determination of Internal Exposure -
OUESTION 372: When monitoring of internal exposure is required by 10 CFR 20.1502,10 CFR 20.1204(a) requires the licensee to take " suitable and timely" measurements. Will NRC define what is suitable and timely to avoid differences of opinion among inspectors?
ANSWER:
No.
Some general guidance on what is suitable and timely will be included in Regulatory Guide 8.9, Revision 1, " Acceptable Concepts, Models, Equations, and Assumptions for a Bioassay Program." Other than this general guidance, the NRC staff has no plans to provide a definition of what is -
" suitable and timely." That definition depends on the circumstances of the particular exposure. What is " suitable and timely" under new Part 20 is (as before, under old Part 20) a matter of professional judgement in a good radiation protection program. NRC management will resolve any " differences of opinion among inspectors" that are called to its attention.
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References:
10 j
CFR 20.1204, 20.1502) 1 1
[
10 CFR 20.1208 Dose to an Embryo / Fetus OVESTION 382:
Do NRC regulations allow a declared pregnant woman to
-l "undeclare" her pregnancy?
If so, does this withdrawal of a previous declaration of pregnancy also oblige the licensee to withdraw restrictive measures and enhanced monitoring established solely to comply with related embryo / fetus dose limits?
ANSWER:
Yes, to both questions.
Under the regulations (which are consistent with the Supreme Court decision in the case of UAW vs. Johnson Controls), a woman has the right to choose whether or not to declare her pregnancy, including the right to revoke her declaration.
It is the woman's right to choose, not the declaration of pregnancy, that is irrevocable. Note:
A-woman's withdrawal of her declaration of pregnancy does not alter the requirement of 10 CFR 20.2106(e) that the licensee (continue to) maintain the 1
records of dose to the embryo / fetus (that were prepared as a result of the i
woman's declaration of pregnancy).
See Regulatory Guide 8.7, Rev. 1, Section 2.3, concerning reporting of the embryo / fetus dose on request of the monitored woman.
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Reference:
10 CFR 20.1301 Dose for Individual Members of the Public OVESTION 384:
Nuclear power plant licensees are required to meet the criteria in 10 CFR 50 Appendix 1 and 40 CFR 190 with regards to maintaining doses to individual members of the public ALARA.
Related Regulatory Guides (e.g.,
1.21,1.109, and 4.1) describe programs which are acceptable to the NRC staff to demonstrate compliance with 10 CFR 50 Appendix I and 40 CFR 190 criteria.
Specific requirements for monitoring, sampling, dose calculation and reporting i
are included in each plant's Technical Specifications and related Offsite Dose l
Calculation Manual.
Does compliance with plant Technical Specifications, applicable Regulatory Guides, and the radiation standards in 40 CFR 190 fully meet the requirements of 20.130l? The purpose in asking this question is to obtain clarification that, although the revised 10 CFR 20 introduces new dose limits for individual members of the public and nc3 effluent concentration values in 10 CFR 20 Appendix B, the scope of monitoring, sampling, dose calculation and reporting are not changed for nuclear power plants by the revised 10 CFR 20 from the previously applicable requirements and guidance.
ANSWER: Not necessarily.
See previous questions and answers under 10 CFR 20.1301 and 20.1302 in the previous four sets of questions and answers.
Generally, for nuclear power plants, no Major changes are needed in "the scope of monitoring, sampling, dose calculation, and reporting" that has been adequate for compliance with plant Technical Specifications and 40 CFR 190, and for conformance with applicable regulatory guides.
However, some relatively minor changes may be needed.
For example, at some plants, changes
_g_
i may be needed for demonstrating compliance with the requirements of 10 CFR. 20.1301 as they apply in members of the public in controlled areas.
(See question 104 and answer in the third set of questions and answers.)
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References:
10 CFR 20.1301, 20.1302).
i 10 CFR 20.1502 Conditions Reauirino Individual Monitorina OVESTION 375:
In supporting a conclusion that individual monitoring of internal occupational dose is not required [10 CFR 20.1502(b)] and, therefore, that summing of-internal and external dose is not required [10 CFR 20.1202(a)], what is considered to be acceptable for bioassay frequency, DAC-hour administrative limit, and whole-body counting minimum testing level?
ANSWER: Under 10 CFR 20.1502(b), there is no required frequency for bioassay, I
DAC-hour administrative limit, or minimum testing level for whole-body counting either for individuals for whom monitoring is required or to support i
a conclusion that individual monitoring is not required.
However, the answer to question 54 (under section 20.1502 in the first set of questions and answers) provided a number of examples of measures that could be used at nuclear power plants to verify that the expected degree of' respiratory protection will be achieved so that the concentrations of radionuclides in air after credit is taken for respiratory protection may be used in making the
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prospective assessment that individual monitoring for internal dose is not.
required. These measures " include, (but are not limited to) measurements of nasal smears from workers who have used respirators and whole body counting, relatively soon after a job, of one or more workers among a group of workers who wore respiratory protective equipment while working on the job and j
periodic whole-body counting (e.g., annually) of all workers who wear respiratory protective equipment."
It should be recognized that in addition to the bioassay requirements of 10 CFR 20.1502(b), there is the bioassay requirement of 10 CFR 20.1703(a)(3)(ii),
i which is related to the use of individual respiratory protection equipment.
If whole body counting is to be used to verify the effectiveness of the respiratory protection program, it must be able to demonstrate that estimates of intake based on exposure calculations (i.e., on air concentrations and on taking credit for protection factors) are consistent with estimates of intake 3
based on bioassay. The licensee should take into account the fact that demonstrating effectiveness of the respiratory protection program'may have to be based on exposures over durations much shorter than a year, particularly for materials that are expected to be cleared rapidly from the body.
Some general guidance on air sampling is provided in Regulatory Guide 8.25, Rev.1, (which states that this guide does not apply to reactor facilities), and general guidance on bioassay will be provided in Regulatory Guide 8.9, Rev.1.
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References:
10 CFR 20.1502, 20.1202, 20.1703, Regulatory Guide 8.9) i i
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.. l OUEST10N 398:
Regulatory Guide 8.7 (Section C.2.2) states that "if during the j
course of the year the dose to date for the year exceeds 1 rem CEDE [ committed effective dose equivalent) or the individual receives an overexposure in another dose category, the CDE [ committed dose equivalent) to the maximally exposed organ must be calculated, recorded and reported."
If an individual arriving from work at another (previous) licensee's facility within the current year has a CEDE that exceeds 1 rem, does the guidance imply requirements for monitoring, recording or reporting of internal dose, even if the present licensee's prospective evaluation shows that the individual is not I
"likely to exceed" 10% of an annual limit on intake (ALI)?
ANSWER:
For the situation described in the question, the quoted section of the Regulatory Guide 8.7 indicates that the previous licensee should have calculated, recorded, and should report the CDE to the maximally exposed organ.
However, as indicated in Section C.I.1 of Regulatory Guide 8.7, in performing the prospective evaluation (under 10 CFR 20.1502) to determine if monitoring is required "for individuals who received exposure at other facilities in the current year, the previous dose need not be considered in prospective evaluation. Only the dose that could be received at the facility performing the evaluation need be considered when determining the need for monitoring and, therefore, the recordkeeping and reporting requirements."
(
References:
10 CFR 20.1502, Reg. Guide 8.7).
OVESTION 126:
Individuals performing assigned duties are often exposed to small amounts of radiation from plant effluents at licensees' sites under i
normal operating conditions.
(a) If these individuals are likely to receive, or have already received, in excess of 10% of an occupational dose limit from i'
external sources, does the licensee have to determine, record, and report doses from the effluents to comply with the revised Part 207 (b) If so, what are the monitoring thresholds for the external and internal components of the dose?
ANSWER:
(a) Yes.
In-this case, the licensee would have to monitor and record i
the external dose from the effluents, since the individuals are in excess of 10% of the occupational dose limit from all external sources (20.1502(a)).
However, the licensee is not required to monitor the effluent dose separately from other external doses.
(b) The licensee must monitor and record the internal occupational dose only if the individuals are likely to receive in i
excess of 10% of the applicable ALIs from all occupational intakes of radioactive material. Note:
For nuclear power plants., the preceding answer does not mean that all workers for whom monitoring of external dose is required must wear their personal dosimeters at all times while on site.
Such workers in controlled areas (outside restricted areas) need not wear personal t
dosimeters to measure external doses from effluents. However, they should wear personal dosimeters in a controlled area when performing work that has the potential for significant occupational exposure (e.g., performing a radiation survey of a vehicle loaded with a shipment of radioactive material.)
(
Reference:
10 CFR 20.1502) i I
m
h 10 CFR 20.1601 Control of Access to High Radiation Areas OUEST10N 373: What are the minimum requirements for height and access restrictions of barriers used to prevent entry to locked high radiation areas (HRAs) and very high radiation areas (VHRAs) at nuclear power plants?
i ANSWER:
The NRC has prepared Regulatory Guide 8.38 that details control measures that should be implemented for such areas. This regulatory guide provides guidance on the following program elements as related to control of locked HRAs and VHRAs: management controls, procedural controls, training, communications and physical controls.
In general there are no prescriptive, specific minimum height requirements for barriers used to prevent entry to locked HRAs and VHRAs.
It is required that physical controls (such as barriers) provide assurance that individuals are not gaining unauthorized access to locked HRAs.
For VHRAs, 10 CFR 20.1602 requires " additional measures to ensure that an individual is not able to gain unauthorized or inadvertent access." The NRC staff realizes that tools (wrenches, wire cutters, cutter torches) are readily available in a nuclear power plant and that it is virtually impossible to prevent determined willful circumvention of physical barriers. However, physical controls can and should
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be established so that any such willful acts are detectable (i.e., they result in cut locks or fencing, wall panels removed, etc).
For example, the use of a fence to prevent access to a VHRA would not satisfy the requirements of 10 CFR 20.1602 if an individual could gain access to the VHRA by climbing over the fence.
(
References:
10 CFR 20.1601, 20.1602)
P OUESTION 385:
Do licensees have discretion regarding the form and applicability of additional posting and barriers for individual high radiation areas (HRAs) that are located within a larger area posted and barricaded (e.g., with a locked door) as an HRA or inside a posted HRA control point?
If licensees must post and barricade such individual HRAs at each area's entrance, then " double posting" results. Double posting has long been a concern due to the confusion that it might create for workers. The need to clearly identify to workers areas with high radiation levels might be accomplished through posted survey maps, " hot spot" stickers, or other means.
In addition to effectively accomplishing the need for notifying workers of high radiation areas, these methods may be preferable to posting and barricading each HRA, located as described above, due to potential dose savings that could result from fewer entries into the area solely for the purpose of verifying the secondary postings and barriers.
This question is intended to establish flexibility in implementation, appropriate to the circumstances, to maintain control over access and inform workers in an effective and efficient manner.
ANSWFR:
Power reactor licensee discretion and flexib'ility;with respect to posting and barriers for high radiation areas is the same under new Part 20 and applicable Technical Specifications as it has been under old Part 20 and applicable Technical Specifications.
Existing guidance on control and posting of high radiation areas is contained in the Health Physics Positions (HPPOS)
e Data Base (NUREG/CR-5569). The particular question of individual HRAs that are located within a larger posted and barricaded HRA or inside a posted HRA control point is addressed in the documents identified as HPPOS-14 and HPPOS-66 in NUREG/CR-5569. HPPOS-66 is IE Information Notice No. 84-82, " Guidance for Posting Radiation Areas," dated November 19, 1985. Other related guidance is contained in HPPOS-036, HPPOS-234, HPPOS-242, and HPPOS-210. This guidance will continue to be applicable under the new Part 20.
Regulatory Guide 8.38 also contains guidance on this subject for nuclear power plants.
For most material licensees, posting and access control requirements contained in 10 CFR Parts 20, 34, 35, and 36 should be adequate.
More detailed information and requirements would be contained in individual licenses and license applications.
(
References:
10 CFR 20.1601, 20.1902).
10 CFR 20.1702 Use of Other Controls QUESTION 386:
The question relates to the following example.
In evaluating whether to require the use of respirators to limit intakes it is determined that wearing a respirator will likely increase the total effective dose equivalent (TEDE).
However, the workers request that they be allowed to wear respirators to limit intakes, despite the results of the evaluation.
With regard to NRC regulation, what discretion may the licensee exerci:e in this circumstance?
ANSWER:
10 CFR 20.1702 provides for the use of respirators consistent with maintaining the TEDE as low as is reasonably achievable. Assuming that the licensee has provided appropriate t-aining to the workers in question, the licensee may exercise discretion on a case-by-case basis in determining whether to grant approval to a worker's request for using a respirator when the TEDE-ALARA determination dictates that respiratory protection not be used.
The NRC staff realizes that the significant " culture shift"/" paradigm shift" (i.e., changing from the traditional operational philosophy of not allowing any worker intakes to one of allowing some intakes when this is consistent with the goal of maintaining the TEDE ALARA) may not take place quickly.
Furthermore, acceptance of this change will certainly be difficult for some individuals. Therefore, the NRC staff realizes that during this transition period licensees will need reasonable flexibility to allow for individual needs and problems in making this shift. However, the staff expects that over time the transition to ALARA-TEDE will be made and this worker acceptance problem will become an exceptional occurrence.
In the meantime, when assigning a respirator to the requesting worker, the licensee should make every reasonable effort to provide the worker with a respirator that minimizes the loss of worker efficiency.
Note: The NRC staff is aware of existing state OSHA regulations that reauire an employer to provide a worker with a respirator upon request; compliance with such state regulations is acceptable to the NRC staff.
See related question 387.
(
Reference:
10 CFR 20.1702, 20.1703).
l
. OVEST10N 387:
In evaluating the use of respirators to limit intakes, in addition to determining the total effective dose equivalent (TEDE), should the evaluation and subsequent decision on whether to use respirators also consider industrial safety hazards associated with wearing respirators? For example, added effort increasing the probability of heat stress, limited range of vision while climbing, or difficulty of maneuvering readily while working in confined spaces due to wearing a respirator may pose potentially greater safety risks than does the potential dose from uptake of airborne radioactive material to which an individual might be exposed by not wearing a respirator.
l ANSWER:
10 CFR 20.1702 provides for the use of respirators consistent with maintaining the TEDE as low as is reasonably achievable. A reduction in the TEDE for a worker is not reasonably achievable if an attendant increase in the worker's industrial health and safety risk would exceed the benefit to be i
obtained by the reduction in the radiation risk associated with the reduction in the TEDE. The NRC has never maintained that application of the ALARA principle requires ignoring factors other than radiation that may have an adverse impact on public health and safety.
(
References:
10 CFR 20.1702, 20.1703).
OVESTION 388:
In regard to Question 91 (previously answered in the third set of Q&As), can NIOSH approved respiratory equipment which makes use of a combination particulate filter and iodine sorbent with a protection factor for particulates be used in a mixed particulate and iodine atmosphere to limit intakes? This practice would seem valid for equipment that is NIOSH approved and has a protection factor for particulates.
ANSWER:
Yes.
However, there is no assigned protection factor for radiciodine with this equipment.
[The NRC may authorize radioiodine protection factors for this equipment in accordance with 10 CFR 20.1703(b)(2) as it has previously authorized them in accordance with 10 CFR 20.103(d).]
(
References:
10 CFR 20.1702, 20.1703).
10 CFR 20.1703 Use of Individual Respiratory Protection Eauipment OVESTION 374:
In general, do established respirator effectiveness programs at nuclear power plants meet the intent of the regulation in providing assurances of the effectiveness of chosen respiratory protection?
ANSWER:
Yes. There is no explicit requirement in 10 CFR Part 20 for a
" respirator effectiveness program" other than the requirement of 10 CFR 20.1703(a)(3)(ii) for " surveys and bioassays, as appropriate, to evaluate actual intakes."
10 CFR 20.1704 specifies that the Commission may impose additional restrictions to ensure that the respiratory protection program is adequate and to limit the extent to which a licensee may use respiratory protection equipment instead of process or other engineering controls.
The NRC staff does not anticipate a need to impose further restrictions on the use of respiratory protection equipment at nuclear power plants pursuant to 10 CFR
i 20.1704. Also as indicated in the (revised) answer to Question 54,
~
information from a " respirator effectiveness program" can be used to justify j
the assumption that the concentrations of radionuclides in air to be used for 1
determining whether or not monitoring is required [ pursuant to 10 CFR 20.1502(b)] are the concentrations that include credit for the assigned protection factors when respirators are to be used, rather than the concentrations without that credit. See related question 376.
(
References:
- 20. 1703, 20.1704, 20.1502) 10 CFR 20.1902 Postina Reauirements OVESTION 379:
Should radioactive noble gas concentrations be excluded (a) with regard to evaluating and posting Airborne Radioactivity Areas and (b) in determining Derived Air Concentration-hours (DAC-hours)7 The definition of Airborne Radioactivity Area refers to areas where airborne radioactivity concentrations exceed the DAC values or where an individual could exceed 12 DAC-hours in a week. DAC is defined as the " concentration of a specific radionuclide in air which, if breathed...results in an intake of one ALI
[ Annual Limit on Intake]." The values listed for radioactive noble gases in the DAC column in 10 CFR 20 Appendix B are identified as " submersion" values that apply to external, rather than internal, exposure. Also, there are no ALI values listed in 10 CFR 20 Appendix B for radioactive noble gases.
From this, it appears that radioactive noble gas concentrations do not apply to evaluating and posting Airborne Radioactivity Areas or to DAC-hour determinations.
ANSWER:
(a) Radioactive noble gas concentrations should not be excluded with regard to evaluating and posting airborne radioactivity areas.
See the.
discussion below.
(b) Radioactive noble gases of the " submersion" class (which have no inhalation ALI) should be excluded in determining DAC hours for use in determining the committed effective dose' equivalent (CEDE).
In other words, the DACs for noble gases are based on external dose and should not be used to assess internal dose.
Discussion:
The following discussion relates to the posting question.
Although the definition of DAC in 10 CFR 20.1003 does not include concentrations calculated on the basis of the external dose resulting from
" submersion," Appendix B clearly states that the DAC values listed in Table 1 of Appendix B " relate to one of two modes of exposure:
either external submersion or the internal committed dose equivalents resulting from inhalation of radioactive materials." The definition of " airborne radioactivity area" refers to "... concentrations - (1) In excess of the derived air concentrations (DACs) specified in Appendix B...."
Thus, the definition of " airborne radioactivity area" includes the DACs in Appendix B that are noble gases and that are based on " submersion." The preamble to new Part 20 (56 FR 23379, second and third columns) also indicates that areas that meet the definition of " airborne radioactivity area" because of the presence of noble gases are required to be posted.)
(
References:
10 CFR 20.1902, 20.1003).
\\
10 CFR 20.2001 Waste Disposal - General OVESTION 376:
" Decay in storage" is one means of waste disposal authorized in the new Part 20 [10 CFR 20.2001(a)(2)]. How can " decay in storage" be used for wastes (a) at nuclear power plants and (b) at materials facilities?
ANSWER:
(a) The inclusion of the " decay in storage" option in new Part 20 l
does not provide any new options for waste disposal at nuclear power plants.
See the discussion of " decay in storage" in the preamble to new Part 20 (56 FR 23380-23381).
" Decay in storage" is a practical means of disposal only for radionuclides with short half lives. Wastes from nuclear power reactors usually include radionuclides whose half lives are too long for application of the " decay in storage" option.
In any case, wastes that are to be released to unrestricted areas after having decayed in storage must meet the requirements of one of the other allowed forms of waste disposal in Part 20, or the requirements of 535.92, " Decay in-storage," of 10 CFR Part 35 or the specific requirements given in the applicable NRC or Agreement State License conditions. However, the requirements of $35.92 of Part 35 are not applicable to Part 50 licensees.
(b) As indicated in the answer to part (a) of this question, wastes that are to be released to unrestricted areas after having decayed in storage must meet the requirements of one of the other allowed forms of waste disposal in Part 20, or the requirements of 635.92, " Decay in Storage," of 10 CFR Part 35 or the specific requirements given in the applicable NRC or Agreement State License conditions.
For medical licensees (under 10 CFR Part 35), requests for specific license amendments providing exemptions from 10 CFR 35.92 may be considered by the NRC for approval based on extraordinary circumstances, in accordance with 10 CFR 35.19, provided that the licensee demonstrates a real need for the requested exemption. These exemption requests to NRC Regional Offices will be reviewed at NRC Headquarters on a case-by-case basis under a technical assistance request from the Regional Office.
See The answer to Question 389 for additional discussion of decay in storage.
(
Reference:
4 00ESTION 389: The revised 10 CFR 20 includes a new provision that allows disposal of licensed material "...by decay in storage..." What criteria should be used in implementing this provision? Is the NRC planning to develop generic guidance for " decay in storage"?'
ANSWER:
See the answer to question 376 for a discussion nf " decay in storage." As indicated in that answer, " decay in storage" is not a practical means of disposal of licensed material at nuclear power plants (and at some other facilities). Therefore, the NRC is providing no criteria to be used in implementing this provision at nuclear power plants and is not planning to develop (additional) generic guidance for " decay in storage" at nuclear power plants. As noted in the statement of considerations for new Part 20 (56 FR 23380, third column, and 23381, first column), technically, the " decay in
t -
storage" option has always been available to licensees as an allowed waste disposal option. This option was formally included in the proposed and final rules because the list of disposal options is exclusive and there had been questions as to whether this option is allowed under 5520.1-20.601 (in old Part 20).
It should be noted that this option does not allow material that has " decayed in storage" to be released to an unrestricted area unless it meets the requirements of one of the other allowed forms of waste disposal in part 20, or the requirements of 535.92, " Decay in Storage," of 10 CFR Part 35, or the specific requirements given in any NRC or Agreement State license.
(
References:
10 CFR 20.2104 Determination of Prior Occupational Dose QUESTION 371:
10 CFR 20.2104(c)(1) states that a licensee may accept, as a record of the occupational dose that the individual received during the current year, a written signed statement from the individual.
If this was done and the statement is false, would a resulting exposure greater than 5 rem l
in the year be considered an overexposure and a violation?
r ANSWER: The exposure would be an " overexposure" (an occupational dose in excess of the annual limit). However, as indicated in the statement of considerations for the new Part 20 (56 FR 23384, first column) if the i
individual deliberately falsifies the statement, the licensee would not be i
penalized for a resulting overexposure.
Furthermore, the staff believes that the licensee should not be penalized for false information provided by the individual even if the falsification was not deliberate. However, as indicated in Regulatory Guide 8.7, Rev. 1, although not required by the regulations, it is considered good health physics practice to verify the information on prior exposure provided by the individual.
Such verifications should reduce the likelihood of overexposure resulting from false information on prior exposures.
If an individual deliberately provides false information on the prior dose, that individual would be in potential violation of the new regulations covering the " deliberate misconduct" (56 FR 40664, 8/15/91) that caused the licensee to be in violation of the regulatory limit.
(
Reference:
10 CFR 20.2104) l Dl!ESTION 390: During 1993, there may be radiation workers transiting between licensees that have, and have not, implemented the revised Part 20.
(a) In the case of a worker whose. dose was monitored earlier in the year at a licensee that has implemented the revised Part 20 and is now inprocessing at a licensee that has not implemented the revised Part 20:
(1) Should "whole body 1
1 dose" be taken as the " total effective dose equivalent" (TEDE) or as the " deep dose equivalent" (DDE) recorded by the previous licensee?
(2) If the individual has received dose in excess of an "old" Part 20 limit for the current quarter, but less than the respective revised Part 20 limit for the year (e.g., shallow dose equivalent to an extremity of 20 rems for both the
. current quarter and year to date), is the individual unavailable for any i
further exposure in that dose category for the remainder of the quarter?
(3) 1 If the individual has received dose in excess of the " implied annual limit" of the "old" Part 20, but less than the respective annual limit in the revised Part 20 (e.g., shallow dose equivalent to the skin of 35 rems in the current quarter and year to date), is the individual unavailable for further exposure in that dose category for the remainder of the year?
(4) If the individual has received a planned special exposure (PSE) at the previous workplace in the current quarter, how should the PSE dose be accounted for as prior occupational dose by the present licensee under the "old" Part 207 Should the PSE dose be subtracted from the available current quarter dose for that dose category?
(b) In the case of a worker whose dose was monitored earlier in the year at a licensee that has not implemented the revised Part 20 and is now inprocessing at a licensee that has implemented the revised Part 20:
if the individual has received recorded internal dose (in terms of rem) or internal exposure (in terms of MPC-hrs) or internal uptake (in terms of organ burden), how should this data be considered with regard to revised Part 20 requirements (i.e.,
ANSWER:
(a) (1) DDE.
(2) Yes, the individual is " unavailable for any further exposure in that dose category for the remainder of the quarter-because the individual has already exceeded the applicable dose limit for the quarter.
(3) The individual is unavailable for further exposure in that dose category for the remainder of the quarter (because the individual has exceeded the applicable dose limit for the quarter), but is available for further exposure in that dose category for the remainder of the year after the end of the quarter.
(4) The PSE dose should be accounted for as occupational dose received during the quarter and should be subtracted from the available current quarter dose for the dose category.
(b) CEDE.
(
Reference:
RUESTION 64: The following question relates to the requirements of 10 CFR 20.2104(a)(2), 20.2104(c), and 20.2104(d) concerning records of lifetime cumulative occupational dose. Assuming that (1) the licensee has obtained, by electronic media, a printed report (or reports) containing the Form 4 information on an individual's lifetime cumulative dose, (2) the individual who received the dose signed Form 4, or equivalent, in accordance with 10 CFR 20.2104(d), and (3) there is no other signature attesting to the authenticity of the Form 4 record.
Is the licensee in compliance with the requirements in 10 CFR 20.2104 concerning records of lifetime cumulative occupational dose?
ANSWER:
Yes. As stated in Regulatory Guide 8.7, Section C.l.3, to
[
demonstrate compliance with the requirement of 10 CFR 20.2104(a)(2) (to attempt to obtain the records of lifetime cumulative occupational radiation dose), the individual to be monitored may provide a written estimate of the cumulative lifetime dose or an up-to-date NRC Form 4 signed by the individual.
I
. This information does not need to be verified so long as the individual does not participate in a planned special exposure. However, in the unlikely event that it was the individual _ who provided the licensee with the report by electronic media, Regulatory Guide 8.7, Section C.I.3, also states that "Although not required by the regulations, it is considered good health
)
physics practice to verify the information provided by the individual."
(
Reference:
OUESTION 408:
Background
10 CFR 20.2104 states that for each individual for whom monitoring is required, the licensee must-
- 1) Determine the occupational radiation dose for the current year; and
- 2) Attempt to obtain the records of lifetime cumulative occupational radiation dose.
" Records of lifetime cumulative occupational radiation dose" refers to occupational dose records prior to the current year. These records are only used when implementing the planned special exposure option.
Some licensees may use prior year's TEDE to control an individual's lifetime dose in compliance with NCRP-91 recommendations or average annual exposure in compliance with ICRP-60 recommendations. However, i
other prior year's dose quantities such as shallow dose equivalent (SDE) and lens (eye) dose equivalent (LDE) are not useful to licensees and provide no additional protection to individuals.
Therefore, it was i
reasonable and compliant to obtain only TEDE for prior years.
1 Can a licensee seek only to obtain the TEDE occupational dose quantity for prior years to comply with the 20.2104(a)(2) requirement to " attempt to obtain the records of lifetime cumulative occupational radiation dose"?
ANSWER: Yes, provided the licensee does not intend to authorize planned special exposures for the individuals for whom the licensee attempts to obtain only the TEDE.
For planned special exposures, the provisions of 10 CFR l
20.1206(e) that limit " lifetime" exposures apply to all occupational doses having annual limits in 10 CFR 20.1201(a) (TEDE, organ dose, eye dose, skin dose and extremity dose), not just the TEDE. The reasons for this requirement j
other than for use in cases of planned special exposures are given in the i
answer to question 142(b).
(
Reference:
.l i
10 CFR 20.2106 Records of Individual Monitorina Results DUESTION 399: The NRC Form 5 (Item No. 8) provides for entry of multiple NRC license numbers.
Some licensees may hold multiple licenses and provide common monitoring (e.g., a single set of dosimeters) for personnel working under any 1
l
.?
~
& ~
or all of the licenses.
In such cases, it is proposed that only a single NRC form 5 would be generated for each individual, listing all licenses under which they were monitored under 20.1502.
Is this acceptable to satisfy regulatory requirements?
ANSWER:
Yes, in general.
For one nuclear power station, it is acceptable for the licensee to provide a single NRC Form 5 for an individual who works at one or more units at the station.
However, a nuclear utility that has two or more power stations should not use a single NRC Form 5 for an individual who works at two or more different stations; a separate form should be used for each station at which the individual works.
(
References:
10 CFR 20.2106, 20.2206, Reg. Guide 8.7).
{
00ESTION 400: NRC Form 5 (Item No.10B) includes the symbol "V", which is not defined in Regulatory Guide 8.7, Revision 1.
(a) Does the "V" signify " vapor" as used in Federal Guidance Report No. 11?
(b) If so, how is this lung clearance class to be applied in operational air sampling and internal dosimetry programs?
ANSWER:
(a) "V" in Item 10B of Form 5 is an abbreviation for the lung clearance class " vapor" in Appendix B to 10 CFR 20.1001 - 20.2401.
" Vapor" is listed as a lung clearance " class" for only two elements, sulfur and nickel.
(However, the " water" inhalation class for hydrogen-3 indicates water vapor.)
(b) The " vapor" inhalation class should be used when the radionuclides are present in the form of a vapor in the air and the associated air sampling l
should be appropriate for sampling the radionuclides in this form.
(
References:
10 CFR 20.2106, 20.2206, Reg. Guide 8.7).
OUESTION 401:
NRC Form 5 (Item No. 20) provides for the signature of the licensee's authorized representative responsible for the data and is not noted as " optional" as is the licensee signature block on NRC Form 4.
Appendix A of Regulatory Guide 8.7, Rev.1, " Instructions for Recording and Reporting Occupational Radiation Exposure Data," provides for the licensee to sign the l
transmittal letter for electronic transmission of exposure data to the NRC and
~
thereby certify the database.
If a letter certifying the database is maintained on file, can the licensee so note NRC Form 5's which are generated from the database, e.g., " signature on file," rather than signing each individual NRC Form?"
In particular, this would facilitate the providing of individual exposure reports annually to each worker, as required by 10 CFR Part 19.
i ANSWER:
Yes, if the exposure data are reported to the NRC by electronic transmission, the form 5 exposure report prepared from the data base and provided to the worker need not be signed (" signature on file" is acceptable).
However, if the exposure data are provided to the NRC on Form 5, rather than by electronic transmission, the form must be signed. As noted in the question, the signature block on Form 5 is not optional.
(
References:
10 CFR 20.2106, 20.2206, Reg. Guide 8.7, Rev. 1).
i
l OVEST10N 402: NRC Form 5 (Item No. 21, " Comments") implies that dose from a
" hot particle" should be added to the shallow dose equivalent, maximum extremity (SDE, ME - Block 14). However, I&E Notice 90-48 states that " hot i
particle exposure will not be added to skin doses from sources other than hot particles."
(a) Should hot particle doses be added to the shallow dose equivalent as implied?
(b) If so, should this dose be subtracted from the applicable dose category with regard to remaining available shallow dose equivalent (skin or extremity) for the year? Based on our understanding of the intent of I&E Notice 90-48, we believe that " hot particle" doses should not be subtracted from the remaining available shallow dose equivalent (skin or extremity) for the year.
ANSWER: The intent of the " hot particle" example in the instructions for Item i
21 on Form 5 is simply to give one an example of how this space on the form might be used. There is no intention to imply that hot particle doses should be added to other doses. The question of adding hot particle skin doses to other skin doses was addressed in IE Information Notice 90-48, " Enforcement policy for Hot Particle Exposures," and the enforcement policy enclosed with that notice, and in Health Physics Position (HPPOS) 246 (in NUREG/CR-5569).
The NRC policy and staff positions in these documents have not been changed by new Part 20 or the instructions for Form 5 in Reg. Guide. Answers to the specific questions are as follows:
(a) As indicated in HPPOS-246, licensees may choose whether or not to add a hot particle dose to other skin or extremity doses. However, in either case, the record should be clear as to the amount of the hot particle dose.
In determining whether or not an overexposure has occurred, the NRC will consider the hot particle dose alone, without adding it to other doses.
(b) The hot particle dose should not be subtracted from the remaining available shallow dose equivalent (skin or extremity) for the year.
(
References:
10 CFR 20.2106, 20.2206, Reg. Guide 8.7).
i i
OUESTION 403:
NRC Form 5 (Item No.10) provides for listing of specific radionuclides in intakes that contribute to the recorded committed effective dose equivalent (CEDE). When determining the CEDE only significantly I
irradiated organs need be included in the calculations [10 CFR 20.1202(b)(3)].
An organ is considered to be significantly irradiated if the product of the weighting factor and committed dose equivalent, per unit intake, is greater
)
than 10% of the maximum weighted value of committed dose equivalent (CDE), per unit intake [ Footnote I to 20 CFR 20.1202(b)(3)].
Similarly, an isotope need not be considered to be in an airborne mixture if the concentration of any '
radionuclide is less than 10% of its DAC, and the sum of the percentages of 1
the disregarded radionuclides is less than 30% [10 CFR 20.1204(g)].
Given i
these two examples of cut off levels, can a licensee disregard the contribution a radionuclide makes to the CEDE, with regard to recording and reporting specific radionuclides, if it is less than 10% of the total CEDE i
resulting from uptake of a mixture, and the sum of the disregarded radionuclides is less than 30%? In this way insignificant doses, the addition i
of which imply greater precision than exists for internal dosimetry, can be i
disregarded without compromising sound radiological practices.
1 l
i
ANSWER:
No. The statements concerning significantly irradiated organs [in 10 CFR 20.1202(b)(3) and Footnote 1) apply to compliance with requirements for summation of external and internal dose and are not relevant to cutoffs.of radionuclides used in intake calculations. The statement in the question l
concerning the provisions of 10 CFR 20.1204(g) is incorrect; it does not include the necessary condition of 10 CFR 20.1204(g)(1) concerning use of the
" total-activity" in demonstrating compliance.
[See the answer to question 121, in the third set of questions and answers, for clarification of 10 CFR 20.1204(g).] There is no basis in the regulations for the proposed cutoff in the calculation of the CEDE. (
References:
10 CFR 20.2106, 20.2206, Reg. Guide 8.7).
i
_Q_UESTION 404: NRC Form 5 (Item No.10) provides for reporting of individual radionuclides involved in an intake. How does the NRC plan on using this data (i.e., what is the NRC's purpose in collecting this data)?
ANSWER: NRC Form 5 (Item 10) provides for recording / reporting of individual radionuclides involved in an intake because 10 CFR 20.2106, records of individual monitoring results, requires that the records include, when applicable, the estimated intake or body burden of radionuclides.
There are several reasons for inclusion of intake information on Form 5.
One reason is that if the internal dose models and weighting factors are changed at some l
i future date, the NRC can recalculate the reported doses using the new models and weighting factors. Another reason, of benefit to licensees, is to make it l
possible for a licensee to determine the CDE to the maximally exposed organ for an individual who has organ doses reported from previous employers.
For example, consider an individual, who, during a year, was employed by licensee A and received a CDE of 20 rem to the lung, then was employed by licensee B i
and received a CDE of 20 rem to the bone, and finally was employed by licensee C and received a CDE of 20 rem to the thyroid.
NRC Form 5 does not provide a space for recording which organ is the maximally exposed organ (unless the
" Comments" space is used for this purpose).
In the absence of information on which organ was maximally exposed and on the intakes of individual radionuclides, the total CDE to the maximally exposed organ in this example l
would be considered to be the total of these three 20-rem doses (to different organs), or a total of 60 rem, which would appear to be a potential violation i
of the organ dose limit. With the individual radionuclide intake information, the CDE to the maximally exposed organ could be recalculated and very likely j
would be below the limit. The NRC will also use the intake data from some of the earlier reports to the NRC under new Part 20 to recalculate the doses to I
i ensure that the reported doses are reasonably consistent (within a factor of 2 or so).
Finally (as explained in the answer to. Question 142 in the fourth set of questions and answers and in SECY-88-315, which is available in the NRC Public Document Room), the recordkeeping and reporting requirements of new l
Part 20 are consistent with implementing an NRC staff recommendation to establish a registry of radiation workers and their radiation doses.
Such a registry will be of value for a number of reasons, one of which is to facilitate epidemiological studies of potential radiation-induced health effects. The inclusion of the radionuclide intake data in the dose records provides a better basis for these studies than records of dose alone.
(
References:
10 CFR 20.2106, 20.2206, Reg. Guide 8.7).
~_
~ 10 CFR 20.2107 Records of Dose to Individual Members of the Public OUEST10N 391: (a) Are records maintained by nuclear power plants that satisfy the requirements of 10 CFR Part 50, Appendix I, and related regulatory
~
guidance sufficient to demonstrate compliance with the requirements of 20.2107? (b) If not, what additional records are required?
ANSWER:
(a) Not necessarily.
(b) For example, additional records may be needed to demonstrate compliance with the limits for individual members of the public in controlled areas.
See related question 384 and answers (
References:
10 CFR 20.2206 Reports of Individual Monitorina 00ESTION 383:
Reports of planned special exposures (PSEs) are required by 10
[
CFR 20.2204 to be submitted within 30 days of the PSE to the NRC Regional Office. Complete records of PSEs are required to be maintained in accordance with 10 CFR 20.2105 and the monitoring results for PSEs should be recorded on NRC Form 5 or equivalent in accordance with the guidance in Regulatory Guide 8.7, Revision 1.
(a) Are the PSE dose reports also required to be submitted to NRC annually in accordance with 20.22067 (b) If so, is only the NRC Form 5 equivalent required to be submitted, or does the other information required by 10 CFR 20.2105 also have to be included?
(c) Should separate NRC Form 5s, i.e., one for routine dose and one for PSE dose, be submitted for each applicable individual?
ANSWER:
(a) Yes.
(b) Only the information on Form 5._
The information required by 10 CFR 20.2105 does not have to be included in the reports required by 10 CFR 20.2206.
(c) Two separate forms, one for routine dose and i
one for PSE dose should be submitted for each individual who had both routine and PSE doses.
Separate reports are needed because completion of Item 9B on Form 5 requires indicating whether the reported occupational exposure is for routine exposure or for PSE.
In other words, the design of the Form 5 does not allow both routine exposures and PSEs to be reported on the same form.
f
(
References:
10 CFR 20.2206, 20.1206, 20.2204, Reg. Guide 8.7).
OVESTION 392: What monitoring period should be used in annual individual monitoring reports submitted, in accordance with 10 CFR 20.2206, following the j
first year of revised 10 CFR Part 20 implementation, if the period of implementation did not encompass the full year? For example, if a licensee implements the revised 10 CFR Part 20 on July 1,1993, is the licensee required to provide annual individual monitoring reports early in 1994 that cover the entire year, or only for the final six months of the year during
(
which monitoring was provided to individuals under 10 CFR 20.1502?
i f
t ANSWER: This annual report should cover the entire year, preferably using the j
format of Regulatory Guide 8.7, Rev.1 (Form 5) for the entire year. However, if it is impractical to use this format for the portion of the year under 10 CFR 20.1-20.601, the format previously used for reports in compliance with 10 CFR 20.403 (" termination reports") may be used for that portion of the year.
+
(
Reference:
OVESTIOM 393:
Is it acceptable for regulatory purposes that occupational dose data that are being provided on a voluntary basis (i.e., the results of dose monitoring provided that is not required by regulation) be recorded and reported only in part? The purpose in asking this question is to establish whether or not the revised Part 20 provides the flexibility for licensees.to record and report the results of " monitoring performed but not required" without also incurring implied requirements with regards to NRC Forms 4 and 5, or equivalents. The intent is to be able to provide useful information, that is not required by the regulation, on a voluntary basis to the worker and/or the NRC without unduly taxing available licensee resources. The specific example outlined below is provided to illustrate the more general issue of flexibility in recording and reporting occupational dose information that is not necessary for compliance with regulatory requirements.
Some licensees intended to voluntarily record and report the calculated Committed Effective Dose Equivalent (in rem), even when internal monitoring is not required by 10 CFR 20.1502. However, it is not intended that related radionuclide intake data will also be recorded and reported because of the resources which would be needed to track and transfer the specific radionuclide data to the NRC Form 5 or equivalent.
For example, the licensee may only have tracked Derived Air Concentration hours (DAC-hrs), using the appropriate most restrictive DAC, without assessing specific radionuclide 4
intakes. Accordingly, the " Intake" section of the NRC Form 5 would be noted as "NR" for "not required," and no specific radionuclide data would be l
recorded. However, the " Instructions and Additional Information Pertinent to the Completion of NRC Form 5," items 10A-D require that intake data be recorded "...for each radionuclide that resulted in an internal exposure recorded for the individual." The issue is that these instructions should not be considered applicable for recording and reporting performed that is not required. This approach to the partial recording and reporting of occupational dose data, when done on a voluntary basis, appears to be consistent with the flexibility that is implied in the revised Part 20 and i
related regulatory guidance. Note that Regulatory Guide 8.34, Section C.I.4, states "the results of monitoring provided when not required by 10 CFR 20.1502 are not subject to [the] dose recording requirements."
ANSWER: Yes. The instructions for Form 5 do not apply to recording and reporting that is not required by Part 20 and that is being done voluntarily.
1 NRC encourages licensees to report CEDE voluntarily when monitoring is performed even though not required.
If the intake information is omitted when reporting voluntarily, licensees should footnote the CEDE entry with a l
notation in the comments section that " monitoring was not required."
(
Reference:
OVESTION 394:
(a) Are the results of dose monitoring of minors and declared i
pregnant woman performed in accordance with 20.1502 required to be reported to NRC as part of the annual reporting of individual monitoring results?
(b) If so, are the records of dose to the embryo / fetus, which may differ from records of dose to the declared pregnant woman, required to be submitted as part of the annual reporting of individual monitoring results? It would seem that embryo / fetus dose records are not required to be included in the annual report, because the embryo / fetus dose records are developed in accordance with 20.1208, " Dose to the Embryo / Fetus," and not 20.1502, " Conditions Requiring Individual Monitoring of External and Internal Occupational Dose," which is the base reference for the annual reporting requirement.
ANSWER:
(a) Yes.
For a declared pregnant woman, the dose to be reported in accordance with 10 CFR 20.1502 is the dose to the woman herself, not the dose to the embryo / fetus.
(b) No. See Section 2.3 of Reg. Guide 8.7, Rev.
1, concerning reporting of embryo / fetus dose.
(
Reference:
10 CFR 20.2206, 20.1502,20.1208).
OUESTION 395:
If an individual is monitored several times during a year by the same licensee (e.g., during two monitoring periods separated in time), how should the monitoring period (s) be designated in the annual individual monitoring report required by 10 CFR 20.2206 (i.e., on the NRC Form 5 or equivalent)? Due to the possible limitations in the format and structure in licensee's computerized occupational dose recordkeeping systems, it seems that there should be flexibility in meeting the intent of the requirements.
i Alternatives might include the following:
1 (a) Issue one NRC Form 5 or equivalent with a single monitoring period' that begins on the first day of the year and ends on the last day of.the year.
(b) Issue one NRC Form 5 or equivalent with single monitoring period i
that begins on the first day of the first monitoring period and ends on the last day of the last monitoring period.
(c) Issue a separate NRC Form 5 or equivalent for each individual monitoring period (i.e., issue two or more NRC Form 5s for the same individual in the same year).
i Would any or all of these approaches be acceptable in meeting the intent of the regulatory requirements? Would other approaches be acceptable? If so, please describe.
i ANSWB: All three options are acceptable (option B is preferable) provided
.i that the separate " monitoring period (s)" in the question fall within the year used to demonstrate compliance.
10 CFR 20.2206 requires an annual report of monitoring for individuals for whom monitoring was required by 10 CFR 20.1502 during that year (emphasis added).
10 CFR 20.1502 requires monitoring sufficient to demonstrate compliance with the limits. The year as defined-in 10 CFR 20.1003 is the period of time used to demonstrate compliance. Thus,
~
i
the time period for reporting under 10 CFR 20.2206 must be the year as defined in 10 CFR 20.1003 that is used to demonstrate compliance.
(
Reference:
10 CFR 20 Appendix B OVESTION 396:
The Appendix B tables of the revised Part 20 include Alls and DACs for daughter radionuclides, in contrast to the Appendix B tables in the "old" Part 20, which do not include these daughter radionuclides.
For example, ALIs and DACs for rubidium-88 and cesium-138 are listed. Are the listed ALIs and DACs expected to be considered separately with regard to posting and other requirements in the revised Part 20?
ANSWER:
Yes. However, the statements preceding the question itself may.
reflect misunderstandings; these possible misunderstandings are addressed in the following discussion.
The Appendix B tables of both "old" and "new" Part 20 do include many
" daughter radionuclides." The tables of "new" Part 20 include more radionuclides, and therefore more daughter radionuclides, than the tables of "old" Part 20.
Although rubidium-88 and cesium-138 (daughters of krypton-88 and xenon-138, respectively) are not included in "old" Part 20, they do need to be " considered separately with regard to posting and other requirements..."
of "old" Part 20; the relevant concentrations for rubidium-88 and cesium-138 are those listed at the end of Appendix B for "Any single radionuclide not listed above with decay mode other than alpha emission or spontaneous fission and with radioactive half-life less than two hours." The "old" Part 20 does include the rubidium-87 daughter of krypton-87 and the cesium-135 daughter of xenon-135, as well as many other daughters whose parent radionuclides are listed in the tables.
Some very short-lived daughters of long-lived radionuclides are not included in either "old" or "new" Part 20 (e.g., the 2.55-min barium-137m daughter of 30-year cesium-137).
The tables in Appendix B of "old" and "new" Part 20 are consistent with respect to treatment of daughter radionuclides in the dose modeling used to derive the ALIs and DACs listed in the tables. When a listed radionuclide has a radionuclide daughter, the value in the table for that parent radionuclide takes into account the dose from the daughter radionuclide produced in the body from the decay of the parent following intake of the parent (unless a
" submersion" value is listed for the parent). However, the value in the table for a parent radionuclide does not take into account any simultaneous intake i
of the daughter radionuclide. Thus the Alls and DACs for daughter
~
radionuclides need "to be considered separately" from their parent radionuclides "with regard to the posting and other requirements of Part 20."
(
Reference:
- 10 CFR 19.12 Instructions to Workers DUESTION 411:
Under 10 CFR 19.12, what is the minimum training that licensees must provide to visitors who will enter a restricted area (where the occupational dose limits apply)?
ANSWER:
10 CFR 19.12, " Instructions to Workers," requires that training (instruction) be provided to "all individuals working in or frequenting any portion of a restricted area." Frequenting an area means'to pay frequent visits to the area or to be in the area often. Therefore, 10 CFR 19.12 does not apply to infrequent visitors who will not be working in the restricted area.
However,10 CFR 19.12 does apply to visitors or other individuals (a) who will be working in the restricted area pr (b) who are expected to be in the area often.
(Thus, 10 CFR 19.12 does require instruction of anyone working in a restricted area, even if_ that work is infrequent.)
Licensees have the responsibility to determine which individuals are frequent visitors and which are not. Although not required by 10 CFR 19.12, in accordance with good radiation protection practice, infrequent visitor (s) should be provided with a trained escort who will provide the visitor (s) with the information i
needed for protection from any potential radiological hazards.
(
Reference:
o 10 CFR 19.12) 10 CFR 19.13 Notification and Reports to Individuals OVESTION 377: Are licensees required by 10 CFR 19.13 to report to individuals the results of monitoring performed but not required under 10 CFR 20.15027 10 CFR 19.13 states that radiation exposure data shall be reported to the i
individual, and that "the information reported shall include data and results obtained pursuant to Commission regulations orders or license conditions. as shown in records maintained by the licensee pursuant to Commission i
regqul ations.
From this, it appears that the results of monitoring performed
)
but not required by NRC regulations is not required to be reported to individuals.
ANSWER: No. The results of monitoring performed but not required by NRC regulations are not required to be reported to individuals.
(
References:
10 CFR 19.13, 20.1502).
l QUESTION 378:
If a worker formerly monitored at the licensee's facility as a
" declared pregnant woman," requests that her exposure records be forwarded to her current employer, should related embryo / fetus dose records also be forwarded if not specifically requested?
ANSWER: No.
Regulatory Guide 8.7, Rev.1, includes the following statement in Section 3.2.
" Licensees should be sensitive to the issue of personal privacy with regard to embryo / fetus dose.
If requested by a monitored woman,
.. =
a letter report may be provided to document prior embryo / fetus dose."
Otherwise, the embryo / fetus dose records should not be provided.
(
Reference:
10 CFR 19.13, 20.1208).
QUESTION 409:
In complying with the 10 CFR 19.13(c) report request, is it acceptable to report on a Form 4 dose received in the current year as one monitoring period and dose received in prior years as another monitoring period even if the prior years monitoring period exceeds one year?
ANSWER:
Yes. However, it should be recognized that this report should include records of doses received during planned special exposures, accidents, and emergency conditions as shown in the records maintained in accordance with 10 CFR 20.2106.
If there have been no planned special exposures or overexposures, a statement to that effect should be provided.
(
Reference:
10 CFR 19.13) l l
Reactor Technical Soecifications OVEST10N 397: After implementation of the revised 10 CFR Part 20, should nuclear power plant licensees report total effective dose equivalent (TEDE) or deep dose equivalent (DDE) as the "whole body dose" for annual reports.
submitted in accordance with reactor technical specifications and Regulatory Guide 1.167 ANSWER: Deep dose equivalent.
(
Reference:
Reactor Technical Specifications, j
Reaulatory Guide 8.25 QUESTION 405:
Regulatory Guide 8.25 (Section C.I.7) states that "to determine whether the concentration exceeds the DAC over the short term, the sample collection time should not exceed one hour. Shorter sample collection times may be used if desired, but they are not required."
(a) Does this section mean to imply that the duration of a work zone air sample should not exceed one hour if it may be used to determine whether an area needs to be posted or otherwise controlled?
(b) Under what circumstances does this one hour rule apply?
- ANSWER:
(a) No.
The one-hour criterion applies only for sampling used "to determine whether the concentration exceeds the DAC over the short term" (emphasis added).
(b) The one-hour criterion is guidance; it is not a " rule."
See answer to (a) regarding the circumstances of application.
(
References:
Reg. Guide 8.25, 10 CFR 20.1902).
Reaulatory Guide 8.36 OVESTION 406:
Regulatory Guide 8.36, " Radiation Dose to-the Embryo / Fetus,"
(Section C.1.3) states that "the determination of external dose should include all occupational exposures of the declared pregnant worker since the estimated date of conception."
(a) If declared pregnant worker has received occupational dose during this l
pregnancy while working for a previous licensee, is it intended that -the dose from the previous licensee be obtained and included in estimating and limiting the embryo / fetus dose for the gestation period?
(b) If this is the intention, what should be done if appli. cable dose records are not available because the-worker had not declared pregnancy or was not monitored (i.e., was not likely to exceed 10% of a limit) at her previous workplace? In the absence of other data, should the previous dose be assumed to be zero?
Answer:
(a) Yes.
(b) The licensee should make an effort to make a reasonable estimate of the dose using other information that the worker and her previous employer have concerning her exposure.
Even when the worker was not monitored, a well-trained worker and her employer should be able to provide some information concerning her exposure.
(c) No.
Neither should it be assumed to be the maximum possible dose.
See answer to question (b).
i
(
Reference:
l i
t I
t h
i E
fac/ost/re ' &
r woeNny At w Segue. d.n MJ Individuals enter 4*g-a restricted area must be provided training, as 3
appropriate (119.12).
Individuals entering a restricted area must be informed that they are subject to occupational dose limits. -Notet--WWM-and-+thers-who say-4 nfr+quently-en tar-a-re str4cted-a ri a-mu st44-prov44ed - s ee:
4nstruct4cnJac3uding4aing 4nformed-4 hat-they-:re abject-te
-ec< upa14onab40 se-44a44 s-614.12) m Effort must be made to maintain all doses Al.APA (120.1101).
A decision must be made as to whether monitoring is required (120.1502)..
CONTROLLED AREA Controlled areas are not required (120.1003).
~
As in'dicated in the preceding section, an area that satisfies both the definition of a restricted area and the definition of a controlled area is considered to be a restricted area for purposes of compliance with 10 CFR Part 20.
Boundaries of controlled areas may be selected by licensees but should be documented (recorded) (good practice).
Posting of a controlled area as a controlled area is not required
' (520.1902).
Doses received in controlled areas may be occupational doses or public doses. Generally doses will be public doses except when the ifcensee determines that~an individual receives exposure to radiation."in the course of employment..." [i20.1003,if20.1301(b)).
Doses are to be categorized as public doses (d practice) (except for i.e., p'ublic dose limits apply) whenever reasonable and practical (goo occupational doses).
In determining whether an individual in a controlled area is to be categorized as an individual who recefves an occupational dose, or as a member of the general public, the more difficult decisions concern individuals who may be occasionally exposed or whose assigned duties are.
not closely connected to the ifcensed activity. Such individuals include messengers, delivery men and women custodial workers, secretaries, clerical workers, hospital volunteers, etc...Usually, such individuals are considered to be members of the pubite and the doses they receive are well within the limits for members of the public.
1 Hewever, if the assigned duties of these individuals are closely and t
frequently connected to the ifcensed activity, and their doses may approach or exceed the limits for members of the public, the doses such-individuals receive are better treated as occupational doses.
t
-s-1 Only when doses are to be categorized as occupational doses (i.e., occupational dose limits apply) do the following. conditions
=;
apply:
- A decision must be made as to whether monitoring is required (520.1502).
- The licensee should have the ability to exercise positive control.
over the individual's activities in the controlled area.
- The licensee should provide appropriate instructions (cbviou:
-intent-of-61944,--
A
- The licensee should inform the individual that he/she is subject.
to occupational dose limits rather than public dose limits (il9.12-thisisanimpliedrequirement).
INDIVIDUAL MEMBERS OF THE PUBLIC 4
Individuals in controlled areas and unrestricted areas are members of l
the public unless they are receiving an occupational dose (120.1003 &
120.1301).
3 Licensees should apply lower dose limits (public dose limits) to non-workers whenever possible and reasonable (good practice).
An individual is not i member of the public when he/she enters a restricted area (120.1003).
Effort must be raa'de to achieve doses that are ALARA *
(120.1101).
DJLLSILOU6dbh Do occupational dose'11mits or pubite dose limits apply to.-
the doses received by the individuals described in the following scenarios for nuclear pow 6r plants?
1.
Assume an individual employed by a licensee, working at_ a two-unit site 1
(one nuclear plant and one fossil plant), is permanently employed at the i
fossil plant, which is inside the nuclear plant's controlled area. 'The individual does not enter any restricted areas. What dose.ltmits apply to that individual while working at the fossil plant?
2.
What dose limits apply to a pregnant taxi driver while she is picking up anddischargingpassengerswithinthecontrolledarea(outsidethe restricted area) of a nuclear power plant?
t y
y