105 CMR 120.226 - Conditions Requiring Individual Monitoring of External and Internal Occupational Dose

Each licensee or registrant shall monitor exposures from sources of radiation at levels sufficient to demonstrate compliance with the occupational dose limits of 105 CMR 120.200. As a minimum:

(A) Each licensee or registrant shall monitor occupational exposure to radiation from licensed and unlicensed radiation sources under its control and shall supply and require the use of individual monitoring devices by:

(1) adults likely to receive, in one year from sources external to the body, a dose in excess of 10% of the limits in 105 CMR 120.211(A);

(2) minors likely to receive, in one year from sources external to the body, a deep dose equivalent in excess of one millisievert (0.1 rem) a lens dose equivalent in excess of 1.5 millisievert (0.15 rem), or a shallow dose equivalent to the skin or to the extremities in excess of five millisieverts (0.5 rem);

(3) Declared pregnant women likely to receive during the entire pregnancy, from radiation sources external to the body, a deep dose equivalent in excess of one millisievert (0.1 rem). [Note: All of the occupational doses in 105 CMR 120.211 continue to be applicable to the declared pregnant worker as long as the embryo/fetus dose limit is not exceeded];

(4) individuals entering a high or very high radiation area;

(5) individuals working medical fluoroscopic equipment.

(a) An individual monitoring device used for the dose to an embryo/fetus of a declared pregnant woman, pursuant to 105 CMR 120.218(A), shall be located under the protective apron at the waist.

(b) An individual monitoring device used for lens dose equivalent shall be located at the neck (collar), or an unshielded location closer to the eye, outside the protective apron.

(c) When only one individual monitoring device is used to determine the effective dose equivalent for external radiation pursuant to 105 CMR 120.211(C)(2), it shall be located at the neck (collar) outside the protective apron. When a second individual monitoring device is used, for the same purpose, it shall be located under the protective apron at the waist. The second individual monitoring device is required for a declared pregnant woman.

(B) Each licensee shall monitor, to determine compliance with 105 CMR 120.214, the occupational intake of radioactive material by and assess the committed effective dose equivalent to:

(1) adults likely to receive, in one year, an intake in excess of 10% of the applicable ALI in 105 CMR 120.296: Appendix B, Table I, Columns 1 and 2; and

(2) minors likely to receive, in one year, a committed effective dose equivalent in excess of 0.1 millisievert (0.01 rem).

(3) declared pregnant women likely to receive, during the entire pregnancy, a committed effective dose equivalent in excess of 1m Sv (0.1 rem).

(C) Each licensee or registrant shall ensure that individuals who are required to monitor occupational doses in accordance with 105 CMR 120.226(A) wear individual monitoring devices as follows:

(1) An individual monitoring device used for monitoring the dose to whole body shall be worn at the unshielded location of the whole body likely to receive the highest exposure. When a protective apron is worn, the location of the individual monitoring device is typically at the neck (collar).

(2) An individual monitoring device used for monitoring the dose to an embryo/fetus of a declared pregnant woman, pursuant to 105 CMR 120.218(A), shall be located at the waist under any protective apron being worn by the woman.

(3) An individual monitoring device used for monitoring lens dose equivalent, to demonstrate compliance with 105 CMR 120.211(A)(2)(a), shall be located at the neck (collar), outside any protective apron being worn by the monitored individual, or at an unshielded location closer to the eye.

(4) An individual monitoring device used for monitoring the dose to the extremities, to demonstrate compliance with 105 CMR 120.211(A)(2)(b), shall be worn on the extremity most likely to receive the highest exposure. Each individual monitoring device shall be oriented to measure the highest dose to the extremity being monitored.

Notes

105 CMR 120.226

Amended by Mass Register Issue 1373, eff. 9/7/2018.