Chapter DHS 157

DHS 157.22(3)(b) (b) Airborne radioactivity measurements and DAC values may not be used as the primary means to assess the deep dose equivalent when the airborne radioactive material includes radionuclides other than noble gases or if the cloud of airborne radioactive material is not relatively uniform in its distribution of radioactive material in the cloud. The determination of the deep dose equivalent to an individual shall be based upon measurements using instruments or individual monitoring devices.

DHS 157.22(4) (4) Determination of internal exposure.

DHS 157.22(4)(a) (a) For purposes of assessing dose used to determine compliance with occupational dose equivalent limits, a licensee or registrant shall, when required under s. DHS 157.25 (2), take suitable and timely measurements of all of the following:

DHS 157.22(4)(a)1. 1. Concentrations of airborne radioactive materials in work areas.

DHS 157.22(4)(a)2. 2. Quantities of radionuclides in the body.

DHS 157.22(4)(a)3. 3. Quantities of radionuclides excreted from the body.

DHS 157.22(4)(a)4. 4. Combinations of the measurements in subds. 1. to 3.

DHS 157.22(4)(b) (b) Unless respiratory protective equipment is used, as provided in s. DHS 157.27 (3), or the assessment of intake is based on bioassays, a licensee or registrant shall assume that an individual inhales radioactive material at the airborne concentration in which the individual is present.

DHS 157.22(4)(c) (c) When the physical and biochemical properties of the radionuclides taken into the body or the behavior of the material in an individual is known, a licensee or registrant may do any of the following:

DHS 157.22(4)(c)1. 1. Use that information to calculate the committed effective dose equivalent, and, if used, the licensee or registrant shall document that information in the individual’s record.

DHS 157.22(4)(c)2. 2. Upon prior approval of the department, adjust the DAC or ALI values to reflect the actual physical and chemical characteristics of airborne radioactive material, for example, aerosol size distribution or density.

DHS 157.22(4)(c)3. 3. Separately assess the contribution of fractional intakes of Class D, W or Y compounds of a given radionuclide to the committed effective dose equivalent.

DHS 157.22 Note Note: See Appendix E for a description of the pulmonary clearance times of the compounds involved in the exposure.

DHS 157.22(4)(d) (d) If a licensee or registrant chooses to assess intakes of Class Y material using the measurements given in par. (a) 2. or 3., a licensee or registrant may delay the recording and reporting of the assessments for periods up to 7 months, unless otherwise required by s. DHS 157.32 (2) or (3).

DHS 157.22 Note Note: The delay permits the licensee or registrant to make additional measurements basic to the assessments.

DHS 157.22(4)(e) (e) If the identity and concentration of each radionuclide in a mixture are known, the fraction of the DAC applicable to the mixture for use in calculating DAC-hours shall be either of the following:

DHS 157.22(4)(e)1. 1. The sum of the ratios of the concentration to the appropriate DAC value, that is, D, W or Y, from Appendix E for each radionuclide in the mixture.

DHS 157.22(4)(e)2. 2. The ratio of the total concentration for all radionuclides in the mixture to the most restrictive DAC value for any radionuclide in the mixture.

DHS 157.22(4)(f) (f) If the identity of each radionuclide in a mixture is known, but the concentration of one or more of the radionuclides in the mixture is not known, the DAC for the mixture shall be the most restrictive DAC of any radionuclide in the mixture.

DHS 157.22(4)(g) (g) When a mixture of radionuclides in air exists, a licensee or registrant may disregard certain radionuclides in the mixture if all of the following apply:

DHS 157.22(4)(g)1. 1. The licensee or registrant uses the total activity of the mixture in demonstrating compliance with the dose limits in s. DHS 157.22 (1) and in complying with the monitoring requirements in s. DHS 157.25 (2) (b).

DHS 157.22(4)(g)2. 2. The concentration of any radionuclide disregarded is less than 10% of its DAC.

DHS 157.22(4)(g)3. 3. The sum of the percentages under subds. 1. and 2. for all of the radionuclides disregarded in the mixture does not exceed 30%.

DHS 157.22(4)(h) (h) When determining the committed effective dose equivalent, the following information may be considered:

DHS 157.22(4)(h)1. 1. To calculate the committed effective dose equivalent, the licensee or registrant may assume that the inhalation of one ALI, or an exposure of 2,000 DAC-hours, results in a committed effective dose equivalent of 0.05 Sv (5 rem) for radionuclides that have their ALIs or DACs based on the committed effective dose equivalent.

DHS 157.22(4)(h)2. 2. For an ALI and the associated DAC determined by the non-stochastic organ dose limit of 0.5 Sv (50 rem), the intake of radionuclides that would result in a committed effective dose equivalent of 0.05 Sv (5 rem), that is, the stochastic ALI, is listed in parentheses in Table I of ch. DHS 157 Appendix E. The licensee or registrant may, as a simplifying assumption, use the stochastic ALI to determine committed effective dose equivalent. However, if the licensee or registrant uses the stochastic ALI, the licensee or registrant shall also demonstrate that the limit in s. DHS 157.22 (1) (a) 1. b. is met.

DHS 157.22(5) (5) Determination of prior occupational dose.

DHS 157.22(5)(a) (a) For each individual who may enter a licensee’s or registrant’s restricted area and is likely to receive, in a year, an occupational dose requiring monitoring under s. DHS 157.25 (2), a licensee or registrant shall determine the occupational radiation dose received during the current year.

DHS 157.22(5)(b) (b) Before an individual may participate in a planned special exposure, a licensee or registrant shall determine all of the following:

DHS 157.22(5)(b)1. 1. The internal and external doses from all previous planned special exposures.

DHS 157.22(5)(b)2. 2. All doses in excess of the limits, including doses received during accidents and emergencies, received during the lifetime of the individual.

DHS 157.22(5)(c) (c) In complying with the requirements of par. (a), a licensee or registrant may use either of the following means:

DHS 157.22(5)(c)1. 1. Accept, as a record of the occupational dose that the individual received during the current year, a written signed statement from the individual, or from the individual’s most recent employer for work involving radiation exposure, that discloses the nature and the amount of any occupational dose that the individual received during the current year.

DHS 157.22(5)(c)2. 2. Obtain, by telephone, facsimile, electronic media or letter, reports of the individual’s dose equivalent from the most recent employer for work involving radiation exposure, or the individual’s current employer, if the individual is not employed by the licensee or registrant. A licensee or registrant shall request a written verification of the dose data if the authenticity of the transmitted report cannot be established.

DHS 157.22(5)(d) (d)

DHS 157.22(5)(d)1. 1. A licensee or registrant shall record the exposure history, as required by par. (a), on an occupational radiation exposure form provided by the department, or other clear and legible record of all the information required on that form. The form or record shall show each period in which the individual received occupational exposure to radiation or radioactive material and shall be signed by the individual who received the exposure. For each period for which a licensee or registrant obtains reports, a licensee or registrant shall use the dose shown in the report in preparing the occupational radiation exposure form or equivalent. For any period in which a licensee or registrant does not obtain a report, a licensee or registrant shall place a notation on the occupational radiation exposure form or equivalent indicating the periods of time for which data are not available.

DHS 157.22 Note Note: An occupational radiation exposure history form may be obtained by writing to: Department of Health Services, Radiation Protection Section, P.O. Box 2659, Madison WI 53701-2659; or by downloading the form from the Department website at: http://dhs.wisconsin.gov/radiation/Index.htm.

DHS 157.22(5)(d)2. 2. A licensee or registrant is not required to partition historical dose between external dose equivalents and internal committed dose equivalents. Further, occupational exposure histories obtained and recorded on the department’s occupational radiation exposure form or equivalent before the effective date of August 1, 2002, may not have included effective dose equivalent, but may be used in the absence of specific information on the intake of radionuclides by the individual.

DHS 157.22(5)(e) (e) If a licensee or registrant is unable to obtain a complete record of an individual’s current and previously accumulated occupational dose, a licensee or registrant shall assume all the following:

DHS 157.22(5)(e)1. 1. In establishing administrative controls under sub. (1) (f) for the current year, that the allowable dose limit for the individual is reduced by 12.5 mSv (1.25 rem) for each quarter for which records were unavailable and the individual was engaged in activities that could have resulted in occupational radiation exposure.

DHS 157.22(5)(e)2. 2. That the individual is not available for planned special exposures.

DHS 157.22(5)(f) (f) A licensee or registrant shall retain the records on the department’s occupational radiation exposure form or equivalent until the department terminates each pertinent license or registration requiring this record. A licensee or registrant shall retain records used in preparing the occupational radiation exposure form or equivalent for 3 years after the record is made.

DHS 157.22 Note Note: The Department’s occupational radiation exposure history form may be obtained by writing to: Department of Health Services, Radiation Protection Section, P.O. Box 2659, Madison WI 53701-2659; or by downloading the form from the Department website at: http://dhs.wisconsin.gov/radiation/Index.htm.

DHS 157.22(6) (6) Planned special exposures. A licensee or registrant may authorize an adult worker to receive doses in addition to and accounted for separately from the doses received under the limits specified in sub. (1) provided that each of the following conditions is satisfied:

DHS 157.22(6)(a) (a) A licensee or registrant authorizes a planned special exposure only in an exceptional situation when alternatives that might avoid the dose estimated to result from the planned special exposure are unavailable or impractical.

DHS 157.22(6)(b) (b) A licensee or registrant and employer, if the employer is not the licensee or registrant, specifically authorizes the planned special exposure, in writing, before the exposure occurs.

DHS 157.22(6)(c) (c) Before a planned special exposure, a licensee or registrant ensures that each individual involved has been informed and instructed in all the following:

DHS 157.22(6)(c)1. 1. The purpose of the planned operation.

DHS 157.22(6)(c)2. 2. The estimated doses and associated potential risks and specific radiation levels or other conditions that might be involved in performing the task.

DHS 157.22(6)(c)3. 3. The measures to be taken to keep the dose ALARA considering other risks that may be present.

DHS 157.22(6)(d) (d) Prior to permitting an individual to participate in a planned special exposure, a licensee or registrant ascertains prior doses as required by sub. (5) (b) during the lifetime of the individual for each individual involved.

DHS 157.22(6)(e) (e) Subject to sub. (1) (b), a licensee or registrant may not authorize a planned special exposure that would cause an individual to receive a dose from all planned special exposures and all doses in excess of any of the following limits:

DHS 157.22(6)(e)1. 1. The numerical values of any of the dose limits in sub. (1) (a) in any year.

DHS 157.22(6)(e)2. 2. Five times the annual dose limits in sub. (1) (a) during the individual’s lifetime.

DHS 157.22(6)(f) (f) A licensee or registrant maintains records of the conduct of a planned special exposure under s. DHS 157.31 (6) and submits a written report under s. DHS 157.32 (4).

DHS 157.22(6)(g) (g) A licensee or registrant records the best estimate of the dose resulting from the planned special exposure in the individual’s record and informs the individual, in writing, of the dose within 30 days from the date of the planned special exposure. The dose from planned special exposures may not be considered in controlling future occupational dose of the individual under sub. (1) (a) but shall be included in evaluations required by pars. (d) and (e).

DHS 157.22(7) (7) Occupational dose limit for a minor.

DHS 157.22(7)(a) (a) The annual occupational dose limit for a minor is 10% of the annual occupational dose limits specified for adult workers in sub. (1).

DHS 157.22(7)(b) (b) A minor may not work in an area where the minor could receive a deep dose equivalent in excess of .02 mSv (2 mrem) in any one hour unless authorized in writing by the department.

DHS 157.22(8) (8) Dose equivalent to an embryo or fetus.

DHS 157.22(8)(a) (a) A licensee or registrant shall ensure that the dose equivalent to an embryo or fetus during the entire pregnancy, due to occupational exposure of a declared pregnant woman, does not exceed 5 mSv (500 mrem).

DHS 157.22 Note Note: See DHS 157.31 (7) for record keeping requirements.

DHS 157.22(8)(b) (b) A licensee or registrant shall make efforts to avoid substantial variation above a uniform monthly exposure rate to a declared pregnant woman so as to satisfy the limit in par. (a).

DHS 157.22 Note Note: The National Council on Radiation Protection and Measurements recommended in NCRP Report No. 91, “Recommendations on Limits for Exposure to Ionizing Radiation,” June, 1, 1987, that no more than 0.5 mSv (50 mrem) to the embryo or fetus be received in any one month.

DHS 157.22(8)(c) (c) The dose equivalent to an embryo or fetus is the sum of all of the following:

DHS 157.22(8)(c)1. 1. The deep dose equivalent to the declared pregnant women.

DHS 157.22(8)(c)2. 2. The dose equivalent to the embryo or fetus resulting from radionuclides in the embryo or fetus and radionuclides in the declared pregnant woman.

DHS 157.22(8)(d) (d) If the dose equivalent to the embryo or fetus is found to have exceeded 5 mSv (500 mrem), or is within 0.5 mSv (50 mrem) of this dose, by the time the woman declares the pregnancy to a licensee or registrant, a licensee or registrant shall be deemed to be in compliance with par. (a) if the additional dose equivalent to the embryo or fetus does not exceed 0.5 mSv (50 mrem) during the remainder of the pregnancy.

DHS 157.22 History History: CR 01-108: cr. Register July 2002 No. 559, eff. 8-1-02; CR 06-021: am. (1) (a) 2. (intro.), b., and (8) (c) (intro.), r. and recr. (1) (c) 1., Register October 2006 No. 610, eff. 11-1-06; CR 09-062: am. (1) (c) 1. Register April 2010 No. 652, eff. 5-1-10; CR 16-078: am. (4) (h) 2., (5) (d) 1. Register January 2018 No. 745, eff. 2-1-18; correction in (1) (d), (4) (h) 2. made under s. 35.17, Stats., Register January 2018 No. 745.

DHS 157.23 DHS 157.23 Radiation dose limits for individual members of the public.

DHS 157.23(1) (1) Dose limits for individual members of the public.

DHS 157.23(1)(a) (a) A licensee or registrant shall conduct operations to meet all of the following:

DHS 157.23(1)(a)1. 1. The total effective dose equivalent to individual members of the public from the licensed or registered operation may not exceed one mSv (100 mrem) in a year, exclusive of the dose contribution from background radiation, medical radiation exposure, exposure to individuals administered radioactive material and released in accordance with s. DHS 157.62 (8), voluntary participation in medical research programs and the licensee’s or registrant’s disposal of radioactive material into sanitary sewerage under s. DHS 157.30 (3). Facilities with radiation machines installed prior to the effective date of August 1, 2002, that meet the requirements of 5 mSv (500 mrem) in a year are exempt from this requirement.

DHS 157.23(1)(a)2. 2. The dose in any unrestricted area from external sources does not exceed 0.02 mSv (2 mrem) in any one hour, exclusive of the dose contributions from patients administered radioactive material and released in accordance with s. DHS 157.62 (8).

DHS 157.23(1)(b) (b) If a licensee or registrant permits members of the public to have access to controlled areas, the limits under par. (a) 1. for members of the public continue to apply to those individuals.

DHS 157.23(1)(c) (c) A licensee or a registrant or an applicant for a license or registration may apply for prior department authorization to operate up to an annual dose limit for an individual member of the public of 5 mSv (500 mrem). The application shall include all the following information:

DHS 157.23(1)(c)1. 1. Demonstration of the need for and the expected duration of operations exceeding the limit in par. (a).

DHS 157.23(1)(c)2. 2. A licensee’s or registrant’s program to assess and control dose within the 5 mSv (500 mrem) annual limit.

DHS 157.23(1)(c)3. 3. The procedures to be followed to maintain the dose ALARA.

DHS 157.23(1)(d) (d) In addition to the requirements of this section, a licensee or registrant subject to the provisions of the U.S. environmental protection agency’s generally applicable environmental radiation standards in 40 CFR 190 shall comply with those standards.

DHS 157.23(1)(e) (e) The department may impose additional restrictions on radiation levels in unrestricted areas and on the total quantity of radionuclides that a licensee or registrant may release in effluents to restrict the collective dose.

DHS 157.23(1)(f) (f) A licensee or registrant may permit visitors to individuals who cannot be released under s. DHS 157.62 (8). A visitor may receive a radiation dose greater than one mSv (100 mrem) if both of the following conditions are met:

DHS 157.23(1)(f)1. 1. The radiation dose received by the visitor does not exceed 5 mSv (0.5 rem).

DHS 157.23(1)(f)2. 2. The authorized user has predetermined that the visit is appropriate.

DHS 157.23(2) (2) Compliance with dose limits for individual members of the public.

DHS 157.23(2)(a) (a) A licensee or registrant shall make or cause to be made, as appropriate, surveys of radiation levels in unrestricted and controlled areas and radioactive materials in effluents released to unrestricted and controlled areas to demonstrate compliance with the dose limits for individual members of the public in sub. (1).

DHS 157.23(2)(b) (b) A licensee or registrant shall show compliance with the annual dose limit in sub. (1) by either of the following means:

DHS 157.23(2)(b)1. 1. Demonstrating by measurement or calculation that the total effective dose equivalent to the individual likely to receive the highest dose from the licensed or registered operation does not exceed the annual dose limit.

DHS 157.23(2)(b)2. 2. Demonstrating both of the following: