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Radiation Personnel Monitors (Dosimeters)

June 20, 2019 4840

Employees are required to wear dosimeters unless an employer has demonstrated and documented that annual occupational exposure to radiation is less than 10% of 5 rems (0.05Sv). To determine annual occupational radiation exposure, a dentist can hire a health physicist to calculate it or dental staff can wear dosimeters for a period to calculate annual exposure.

Annual occupational radiation exposure should be reevaluated from time to time, especially after new equipment is installed or the facility is remodeled. Documentation of radiation monitoring must be made available to radiation inspectors upon request. Documentation should include type of monitoring device, exchange interval and instructions provided to employees.

Individuals utilizing portable hand-held X-ray systems are required to wear dosimeters, with the exception of users of Aribex Nomad, Aribex Nomad Pro, Nomad Pro2, Aribex Nomad eXaminer and Nomad 75kV. Users of portable hand-held X-ray systems are required to comply with Jan. 26, 2016, CDPH "Amended Exemption to California Code of Regulations Title 17, Section 30311 (6)(4), 30314(0)(5) and 30314(6)(1)."

Reports of occupational radiation exposure should be provided to employees. If an employee is occupationally exposed to radiation at other employers' sites, each employer is responsible for ensuring that the total annual occupational dose to the employee does exceed 5 rems (0.05mSv). A log and form to assist employers with this task is available. 


This list was compiled through an internet search. CDA neither endorses nor guarantees their products and services. You are encouraged to seek references from the vendors. 

Atomic Energy Industrial Labs of the Southwest Inc.
9315 Kirby Drive
Houston, TX 77054

Landauer Inc.

Mirion Technologies
2652 McGaw Ave.
Irvine, CA 92614

MP Bio
9 Goddard
Irvine, CA 92618

PL Medical Company LLC
117 West Dudley Town Road
Bloomfield, CT 06002

Radiation Detection Company
3527 Snead Drive
Georgetown, TX 78626

Stanford Dosimetry LLC
1204 Raymond Street
Bellingham, WA 98229

Regulations pertinent to Occupational Radiation Monitoring

Excerpts from code of federal regulations, Nuclear Regulatory Commission, 10 CFR 20
Incorporated by reference in Section 30253, California Code of Regulations (CCR), Title 17.

Subpart B Radiation Protection Programs Section 20. 1101. Radiation protection programs.

  1. Each licensee shall develop, document, and implement a radiation protection program commensurate with the scope and extent of licensed activities and sufficient to ensure compliance with the provisions of this part. (See § 20.2102 for recordkeeping requirements relating to these programs.)
  2. The licensee shall use, to the extent practical, procedures and engineering controls based upon sound radiation protection principles to achieve occupational doses and doses to members of the public that are as low as is reasonably achievable (ALARA).
  3. The licensee shall periodically (at least annually) review the radiation protection program content and implementation. d.... a constraint on air emissions of radioactive material to the environment ....

Subpart C Occupational Dose Limits Section 20. 1201. Occupational dose limits for adults.

  1. The licensee shall control the occupational dose to individual adults, except for planned special exposures under Section 20.1206, to the following dose limits.
    1. An annual limit, which is the more limiting of- (i) The total effective dose equivalent being equal to 5 rems (0.05 Sv); or (ii) The sum of the deep-dose equivalent and the committed dose equivalent to any individual organ or tissue other than the lens of the eye being equal to 50 rems (0.5 Sv).
    2. The annual limits to the lens of the eye, to the skin, and to the extremities, which are: (i) An eye dose equivalent of 15 rems (0.15 Sv), and (ii) A shallow-dose equivalent of 50 rems (0.50 Sv) to the skin or to any extremity.

Subpart F Surveys and Monitoring

Section 20. 1502. Conditions requiring individual monitoring of external and internal occupational dose.

Each licensee shall monitor exposures of radiation and radioactive material at levels sufficient to demonstrate compliance with the occupational dose limits of this part. As a minimum-

  1. Each licensee shall monitor occupational exposure to radiation from licensed and unlicensed radiation sources under the control of the licensee and shall supply and require the use of individual monitoring devices by--
    1. Adults likely to receive, in 1 year from sources external to the body, a dose in excess of 10 percent of the limits in Section 20.1201 (a). *
    2. Minors and declared pregnant women likely to receive, in 1 year from sources external to the body, a dose in excess of 10 percent of any of the applicable limits in Section 20.1207 or Section 20.1208, and
    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 0.1 rem (1 mSv);2 and
    4. Individuals entering a high or very high radiation area.

Section 20.2106. Records of individual monitoring results.

  1. Record keeping requirement. Each licensee shall maintain records of doses received by all individuals for whom monitoring was required pursuant to Section 20.1502, and records of doses received during planned special exposures, accidents, and emergency conditions. These records must include, when applicable-
    1. The deep-dose equivalent to the whole body, lens dose equivalent, shallow-dose equivalent to the skin, and shallow- dose equivalent to the extremities; and
    2. The estimated intake of radionuclides (see Section 20.1202);
    3. The committed effective dose equivalent assigned to the intake or of radionuclides;
    4. The specific information used to assess the committed effective dose equivalent pursuant to Section 20.1204(c); and when required by Section 20.1502;
    5. The total effective dose equivalent when required by Section 20.1202; and
    6. The total of the deep-dose equivalent and the committed dose to the organ receiving the highest total dose.
  2. Record keeping frequency. The licensee shall make entries of the records specified in paragraph (a) of this section at least annually.
  3. Record keeping format. The licensee shall maintain the records specified in paragraph (a) of this section on NRC Form 5, in accordance with the instructions for  NRC  Form  5,  or  in  clear and  legible records containing  all  the information  required by NRC Form 5.
  4. Privacy protection. (Not included in State regulations.)
  5. The licensee shall maintain the records of dose to an embryo/fetus with the records of dose to the declared pregnant woman. The declaration of pregnancy shall also be kept on file, but may be maintained separately from the dose records.

(The licensee shall retain each required form  or  record until the Commission  terminates  each pertinent  license requiring the record. This includes records required under the standards for protection against radiation in effect prior to January 1, 1994.)