S.C. Code Regs. § 61-63.XII app A
Table 1-Category 1 and Category 2 Threshold
Radioactive material | Category 1(TBq) | Category 1 (Ci) | Category 2 (TBq) | Category 2 (Ci) |
Americium-241 | 60 | 1,620 | 0.6 | 16.2 |
Americium-241/Be | 60 | 1,620 | 0.6 | 16.2 |
Californium-252 | 20 | 540 | 0.2 | 5.40 |
Cobalt-60 | 30 | 810 | 0.3 | 8.10 |
Curium-244 | 50 | 1,350 | 0.5 | 13.5 |
Cesium-137 | 100 | 2,700 | 1 | 27.0 |
Gadolinium-153 | 1,000 | 27,000 | 10 | 270 |
Iridium-192 | 80 | 2,160 | 0.8 | 21.6 |
Plutonium-238 | 60 | 1,620 | 0.6 | 16.2 |
Plutonium-239/Be | 60 | 1,620 | 0.6 | 16.2 |
Promethium-147 | 40,000 | 1,080,000 | 400 | 10,800 |
Radium-226 | 40 | 1,080 | 0.4 | 10.8 |
Selenium-75 | 200 | 5,400 | 2 | 54.0 |
Strontium-90 | 1,000 | 27,000 | 10 | 270 |
Thulium-170 | 20,000 | 540,000 | 200 | 5,400 |
Ytterbium-169 | 300 | 8,100 | 3 | 81.0 |
**The terabecquerel (TBq) values are the regulatory standard. The curie (Ci) values specified are obtained by converting from the TBq value. The curie values are provided for practical usefulness only.
Note: Calculations Concerning Multiple Sources or Multiple Radionuclides
The "sum of fractions" methodology for evaluating combinations of multiple sources or multiple radionuclides is to be used in determining whether a location meets or exceeds the threshold and is thus subject to the requirements of this part.
I. If multiple sources of the same radionuclide and/or multiple radionuclides are aggregated at a location, the sum of the ratios of the total activity of each of the radionuclides must be determined to verify whether the activity at the location is less than the Category 1 or Category 2 thresholds of Table 1, as appropriate. If the calculated sum of the ratios, using the equation below, is greater than or equal to 1.0, then the applicable requirements of this part apply.
II. First determine the total activity for each radionuclide from Table 1. This is done by adding the activity of each individual source, material in any device, and any loose or bulk material that contains the radionuclide. Then use the equation below to calculate the sum of the ratios by inserting the total activity of the applicable radionuclides from Table 1 in the numerator of the equation and the corresponding threshold activity from Table 1 in the denominator of the equation. Calculations must be performed in metric values (i.e., TBq) and the numerator and denominator values must be in the same units.
R1 = total activity for radionuclide 1
R2 = total activity for radionuclide 2
Rn = total activity for radionuclide n
AR1 = activity threshold for radionuclide 1
AR2 = activity threshold for radionuclide 2
ARn = activity threshold for radionuclide n
Statement of Need and Reasonableness:
The following presents an analysis of the factors listed in 1976 Code Sections 1-23-115(C)(1) -(3) and (9)-(11):
DESCRIPTION OF REGULATION: R.61-63, Radioactive Materials (Title A).
Purpose: The Department of Health and Environmental Control proposes amendments to R.61-63 for compliance with federal regulations.
Legal Authority: 1976 Code Section 13-7-40(F)(3) &(10).
Plan for Implementation: The amendments will take legal effect upon publication in the State Register. Department personnel will then take appropriate steps to inform the regulated community of the amendments. Additionally, a copy of the regulation will be posted on the Department's website, accessible at www.scdhec.gov/regulations-table. Printed copies may also be requested, for a fee, from the Department's Freedom of Information Office.
DETERMINATION OF NEED AND REASONABLENESS OF THE REGULATION BASED ON ALL FACTORS HEREIN AND EXPECTED BENEFITS:
The Department amends R.61-63 for compliance with the Commission's federal regulatory updates. The federal Atomic Energy Act of 1954 enable the Commission to enter into agreements with state governors allowing for state regulation of byproduct, source, and special nuclear material. 42 U.S.C. Section 2121. The Commission enters into such agreements if it finds the state regulatory program complies with applicable federal regulations. The amendments are needed in order to renew South Carolina's ongoing agreement with the Commission. The amendments are beneficial in that they ensure state oversight of required standards.
DETERMINATION OF COSTS AND BENEFITS:
Neither the state nor its political subdivisions will incur additional costs through implementation of these amendments. Existing staff and resources will be utilized to implement these amendments to the regulation. The amendments will not create any significant additional cost to the regulated community since requirements or changes to the regulations will be substantially consistent with the current guidelines utilized by the Department.
UNCERTAINTIES OF ESTIMATES:
None.
EFFECT ON THE ENVIRONMENT AND PUBLIC HEALTH:
These proposed amendments seek to ensure an effective regulatory program for radioactive material users under state jurisdiction and protection of the public and worker from unnecessary exposure to ionizing radiation.
DETRIMENTAL EFFECT ON THE ENVIRONMENT AND PUBLIC HEALTH IF THE REGULATION IS NOT IMPLEMENTED:
None. Federal requirements will apply to all affected users. The proposed amendments eliminate possible duplicative or redundant requirements.
S.C. Code Regs. 61-63.XII app A