[Code of Federal Regulations]
[Title 10, Volume 1]
[Revised as of January 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 10CFR20.1202]

[Page 330]
 
                            TITLE 10--ENERGY
 
                CHAPTER I--NUCLEAR REGULATORY COMMISSION
 
PART 20--STANDARDS FOR PROTECTION AGAINST RADIATION--Table of Contents
 
                   Subpart C--Occupational Dose Limits
 
Sec. 20.1202  Compliance with requirements for summation of external 
and internal doses.

    (a) If the licensee is required to monitor under both Sec. Sec. 
20.1502 (a) and (b), the licensee shall demonstrate compliance with the 
dose limits by summing external and internal doses. If the licensee is 
required to monitor only under Sec. 20.1502(a) or only under Sec. 
20.1502(b), then summation is not required to demonstrate compliance 
with the dose limits. The licensee may demonstrate compliance with the 
requirements for summation of external and internal doses by meeting one 
of the conditions specified in paragraph (b) of this section and the 
conditions in paragraphs (c) and (d) of this section.
    (Note: The dose equivalents for the lens of the eye, the skin, and 
the extremities are not included in the summation, but are subject to 
separate limits.)
    (b) Intake by inhalation. If the only intake of radionuclides is by 
inhalation, the total effective dose equivalent limit is not exceeded if 
the sum of the deep-dose equivalent divided by the total effective dose 
equivalent limit, and one of the following, does not exceed unity:
    (1) The sum of the fractions of the inhalation ALI for each 
radionuclide, or
    (2) The total number of derived air concentration-hours (DAC-hours) 
for all radionuclides divided by 2,000, or
    (3) The sum of the calculated committed effective dose equivalents 
to all significantly irradiated\1\ organs or tissues (T) calculated from 
bioassay data using appropriate biological models and expressed as a 
fraction of the annual limit.
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    \1\ An organ or tissue is deemed to be significantly irradiated if, 
for that organ or tissue, the product of the weighting factor, 
wT, and the committed dose equivalent, HT,50, per 
unit intake is greater than 10 percent of the maximum weighted value of 
HT,50, (i.e., WT HT,50) per unit intake 
for any organ or tissue.
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    (c) Intake by oral ingestion. If the occupationally exposed 
individual also receives an intake of radionuclides by oral ingestion 
greater than 10 percent of the applicable oral ALI, the licensee shall 
account for this intake and include it in demonstrating compliance with 
the limits.
    (d) Intake through wounds or absorption through skin. The licensee 
shall evaluate and, to the extent practical, account for intakes through 
wounds or skin absorption.

    Note: The intake through intact skin has been included in the 
calculation of DAC for hydrogen-3 and does not need to be further 
evaluated.

[56 FR 23396, May 21, 1991, as amended at 57 FR 57878, Dec. 8, 1992]