The licensee shall establish and submit for department approval a bioassay program used to evaluate internal doses. At a minimum an acceptable program shall include the following action levels for organ uptakes, corresponding actions taken if these levels are exceeded, frequency of measurement and maintenance of records.
    (1) Routine bioassay is required when an individual handles in open form unsealed quantities of radioactive iodine that exceed those shown in the table 1 below. The quantities shown apply to both the quantity handled at any one time or integrated as the total amount of activity introduced into a process by an employee over any 3-month period.
    TABLE 1
    I-125 or I-131 Activity Handled in Unsealed Form Requiring Bioassay
Type of Operation
Volatile or Dispersible
Bound to Nonvolatile Agent
Processes in open room or bench, with possible escape of iodine from process vessels
1.0 mCi (37 MBq)
1.0 mCi (37 MBq)
Processes with possible escape of iodine carried out within a fume hood of adequate design, face velocity, and performance reliability
1.0 mCi (37 MBq)
10.0 mCi (370 MBq)
Processed carried out within glove boxes, ordinarily closed, but with possible release of iodine from process and occasional exposure to contaminated box and box leakage
10.0 mCi (370 MBq)
100.0 mCi (3700 MBq)
    (a) A bioassay shall be taken within 72 hours of initial use of radioiodine and every 2 weeks thereafter. When radioiodine use is on an infrequent basis (less than every 2 weeks), a bioassay shall be taken within 10 days of the last day of use.
    (b) If the thyroid burden at the time of measurement exceeds 0.12 microcurie (4.44 KBq) of iodine 125 or 0.04 microcurie (1.48 KBq) of iodine 131, the following actions shall be taken:
    1. An investigation of the operations involved, including air and other facility surveys, shall be carried out to determine the cause(s),
    2. Corrective actions that will eliminate or lower the potential for further exposures shall be implemented,
    3. A repeat bioassay shall be taken within 2 weeks of the previous measurement and shall be evaluated within 24 hours after the measurement in order to confirm the presence of internal radioiodines; and,
    4. Notification reports must be provided as required by Rules 64E-5.345 and 64E-5.347, F.A.C., or as required by conditions of the license; and,
    (c) A record of each bioassay shall be maintained for inspection by the department in an auditable form for 3 years and shall include the date of the bioassay, the name of the individual, and the thyroid burden at the time of the measurement.
    (2) Routine bioassay is required when an individual handles in open form unsealed quantities of tritium that exceed those shown in table 2, below. The quantities shown apply to both the quantity handled at any one time or integrated as the total amount of activity introduced into a process by an employee over a 1-month period.
    TABLE 2
    Tritium Activity Handled in Levels or Concentrations Requiring Bioassay
Type of Operation
HTO and Other Tritiated Compounds (Including Nucleotide Precursors)
Tritium (HT or T )
Gas in Sealed Process Vessels
Processes in open room or bench with possible escape of tritium from process vessels.
0.1 Ci ( 3.70 GBq)
100 Ci (3.7 TBq)
Processes with possible escape of tritium carried out within a fume hood of adequate design, face velocity, and performance reliability.
1 Ci (37 GBq)
1,000 Ci (37 TBq)
Processes carried out within glove boxes that are ordinarily closed but with possible release of tritium from process vessels and occasional exposure to contaminated box and leakage.
10 Ci (370 GBq)
10,000 Ci (370 TBq)
    (a) A bioassay shall be taken within 72 hours of initial use of tritium and every 2 weeks thereafter. When work with tritium is on an infrequent basis (less frequent than every 2 weeks), a bioassay shall be taken within 10 days of the last day of use.
    (b) If the urinary tritium concentration exceed 5 microcuries (185 KBq) per liter at the time of the measurement the following actions shall be taken:
    1. An investigation of the operations involved, including air and other facility surveys, shall be carried out to determine the cause(s),
    2. Corrective actions that will eliminate or lower the potential for further exposures shall be implemented,
    3. A repeat bioassay shall be taken within 1 week of the previous measurement and shall be evaluated within 1 week after the measurement. Internal dose commitments shall be estimated using at least two bioassays and other survey data, including the probable times of intake of tritium; and,
    4. Notification reports must be provided as required by Rules 64E-5.345 and 64E-5.347, F.A.C., or as required by conditions of the license; and,
    (c) A record of each bioassay shall be maintained for inspection by the department in an auditable form for 3 years and shall include the date of the bioassay, the name of the patient, and the urinary tritium concentration at the time of the measurement.
Rulemaking Authority 404.051, 404.061, 404.071, 404.081 FS. Law Implemented 404.022, 404.051(1), (4), (6), (9), (10), 404.061(2), (3), 404.071(1), 404.081(1) FS. History-New 2-11-10.