Table 6 -3. Radiation Dose Limits for DOE and DOE Contractors

DOE-STD-1136-2004

Guide of Good Practices for Occupational Radiation Protection in Uranium Facilities

geometries. Conversion coefficients for mono- directional beams of neutrons can be found in an article by

Stewart (Stewart et al. 1994). Conversion coefficients for photons in various irradiation geometries,

including planar sources, can be found in a report by Zankl (Zankl et al. 1994). This approach will provide

more accurate values of effective dose equivalent, as opposed to numerically setting the value of effective

dose equivalent equal to dose equivalent.

Table 6 -3. Radiation Dose Limits for DOE and DOE Contractors

Type of Radiation Exposure

Limit

Occupational Exposures of

Adults

Stochastic Effects

5-rem total per year (sum of effective dose equivalent from external exposures and

CEDE received during year)

Non-Stochastic Effects

Lens of eye

15-rem dose equivalent per year

Extremity

50-rem dose equivalent per year

Skin

50-rem dose equivalent per year

Individual organ or tissue

50-rem dose equivalent per year (sum of dose equivalent from external exposures and

CDE received during the year)

Occupational Exposures of

Minors

Stochastic Effects

0.1-rem per year (sum of effective dose equivalent from external exposures and CEDE

received during year)

Non-Stochastic Effects

10% of occupational dose limits for adults

(Lens of eye, extremity,

skin, individual organ or

tissue)

Embryo/fetus of a

0.5-rem effective dose equivalent per gestation period

Declared Pregnant Worker

Planned Special Exposure

Same as routine occupational dose limits in a year (but accounted for separately )

5 times the routine occupational dose limits over an individual's lifetime

6.1.2 Operational Quantities

Because of the difficulties in determining effective dose equivalent from direct measurements, the

concept of operational quantities has been introduced to be more closely related to measurable quantities.

Operational quantities include ambient dose equivalent used for area monitoring and personal dose

equivalent used for personnel dosimetry. Operational quantities are designed to be a conservative estimator

of effective dose equivalent, i.e., the values of the operational quantities will be equal to or higher than the

effective dose equivalent specified for the limiting quantities.

The ambient dose equivalent, H*(d), is the dose equivalent at a depth, d, in a 30-cm-diameter

sphere of tissue, where: a) the radiation field has the same fluence and energy distribution as the point of

reference for the measurement; and b) the fluence is unid irectional (i.e., the sphere can be viewed as being

in an aligned radiation field). Most survey instruments are designed to measure ambient dose

6-3