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[Federal Register Volume 76, Number 16 (Tuesday, January 25, 2011)]
[Proposed Rules]
[Pages 4258-4260]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-1500]

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DEPARTMENT OF ENERGY

10 CFR Part 835

[Docket No. HS-RM-09-835]
RIN 1901-AA-95

Occupational Radiation Protection; Revision

AGENCY: Department of Energy.

ACTION: Proposed rule and opportunity for public comment.

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SUMMARY: The Department of Energy (DOE) proposes to revise the values 
in an appendix to its Occupational Radiation Protection requirements. 
The derived air concentration values for air immersion are calculated 
using several parameters. One of these, exposure time, is better 
represented by the hours in the workday, rather than the hours in a 
calendar day, and is therefore used in the revised calculations.

DATES: Public comments on the proposed revisions must be received on or 
before February 24, 2011.

ADDRESSES: You may submit comments, identified by Docket No. HS-RM-09-
835 and/or RIN 1901-AA-95, by any of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the instructions for submitting comments.
     E-mail: Judy.Foulke@hq.doe.gov. Include Docket Number HS-
RM-09-835 and/or RIN 1901-AA-95 in the subject line of the message.
     Mail: Dr. Judith D. Foulke, Office of Worker Safety and 
Health Policy (HS-11), U.S. Department of Energy, 1000 Independence 
Avenue, SW., Washington, DC 20585.

FOR FURTHER INFORMATION CONTACT: Judith Foulke, (301) 903-5865, e-mail: 
Judy.Foulke@hq.doe.gov.

SUPPLEMENTARY INFORMATION:

Background

    The requirements in title 10, Code of Federal Regulations, part 835 
(10 CFR part 835), Occupational Radiation Protection, are designed to 
protect the health and safety of workers at DOE facilities. One 
situation that must be addressed is the exposure of workers to 
radioactive material dispersed in the air.

[[Page 4259]]

Based on calculations involving doses to the organs of the body, levels 
of contamination in the air that will not cause the dose limits for 
workers to be exceeded are established for specified radionuclides. 
These values are given in appendix C.
    DOE first published, a final rule on December 14, 1993, (58 FR 
65485), amending 10 CFR part 835. In the June 8, 2007, (72 FR 31903) 
amendment to part 835, DOE revised the values in appendix C to part 
835, Derived Air Concentration (DAC) for Workers from External Exposure 
during Immersion in a Cloud of Airborne Radioactive Material. The 
calculations done for the 2007 amendment were based on a 24-hour day. 
However, to be consistent with other occupational exposure scenarios, 
such as those used in developing the appendix A DACs, an 8-hour per day 
exposure scenario is more reasonable.

Need for Revisions

    This proposed rule revises the values in appendix C to part 835, 
Derived Air Concentration (DAC) for Workers from External Exposure 
during Immersion in a Cloud of Airborne Radioactive Material.

List of Subjects in 10 CFR Part 835

    Federal buildings and facilities, Nuclear energy, Nuclear 
materials, Nuclear power plants and reactors, Nuclear safety, 
Occupational safety and health, Radiation protection, and Reporting and 
recordkeeping requirements.

    Issued in Washington, DC, on January 11, 2011.
Glenn S. Podonsky,
Chief Health, Safety and Security Officer, Office of Health, Safety and 
Security.

    Accordingly, for the reasons set forth in the preamble, part 835 of 
Chapter III of 10 CFR is proposed to be amended as set forth below:

PART 835--OCCUPATIONAL RADIATION PROTECTION

    1. The authority citation for part 835 continues to read as 
follows:

     Authority:  42 U.S.C. 2201, 7191; 50 U.S.C. 2410.

    2. Amend appendix C to part 835, by revising the table to read as 
follows:

Appendix C to Part 835--Derived Air Concentration (DAC) for Workers 
From External Exposure During Immersion in a Cloud of Airborne 
Radioactive Material

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                                                Air Immersion DAC
----------------------------------------------------------------------------------------------------------------
             Radionuclide                       Half-Life                ([micro]Ci/mL)            (Bq/m\3\)
----------------------------------------------------------------------------------------------------------------
Ar-37.................................  35.02 d..................  3E+00...................  1E+11
Ar-39.................................  269 yr...................  1E-03...................  5E+07
Ar-41.................................  1.827 h..................  3E-06...................  1E+05
Kr-74.................................  11.5 min.................  3E-06...................  1E+05
Kr-76.................................  14.8 h...................  1E-05...................  3E+05
Kr-77.................................  74.7 h...................  4E-06...................  1E+05
Kr-79.................................  35.04 h..................  1E-05...................  6E+05
Kr-81.................................  2.1E+05 yr...............  7E-04...................  2E+07
Kr-83m................................  1.83 h...................  7E-02...................  2E+09
Kr-85.................................  10.72 yr.................  7E-04...................  2E+07
Kr-85m................................  4.48 h...................  2E-05...................  1E+06
Kr-87.................................  76.3 min.................  4E-06...................  1E+05
Kr-88.................................  2.84 h...................  1E-06...................  7E+04
Xe-120................................  40.0 min.................  1E-05...................  4E+05
Xe-121................................  40.1 min.................  2E-06...................  8E+04
Xe-122................................  20.1 h...................  8E-05...................  3E+06
Xe-123................................  2.14 h...................  6E-06...................  2E+05
Xe-125................................  16.8 h...................  1E-05...................  6E+05
Xe-127................................  36.406 d.................  1E-05...................  6E+05
Xe-129m...............................  8.89 d...................  2E-04...................  7E+06
Xe-131m...............................  11.84 d..................  5E-04...................  1E+07
Xe-133................................  5.245 d..................  1E-04...................  5E+06
Xe-133m...............................  2.19 d...................  1E-04...................  5E+06
Xe-135................................  9.11 h...................  1E-05...................  6E+05
Xe-135m...............................  15.36 min................  1E-05...................  3E+05
Xe-138................................  14.13 min................  3E-06...................  1E+05
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[FR Doc. 2011-1500 Filed 1-24-11; 8:45 am]
BILLING CODE 6450-01-P
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