4731 RADIATION SAFETY

4731.6110 IRRADIATOR POOLS. Irradiator pools initially licensed after July 1, 1993, must: A. have a watertight stainless steel liner or a liner metallurgically compatible with other components in the pool or be constructed so that there is a low probability of substantial leakage…

4731.6120 SOURCE RACK PROTECTION. If the product to be irradiated moves on a product conveyor system, the source rack and the mechanism that moves the rack must be protected by a barrier or guides to prevent products and product carriers from hitting or touching the rack or mecha…

4731.6130 POWER FAILURES. A. If electrical power at a panoramic irradiator is lost for longer than ten seconds, the sources must automatically return to the shielded position. B. The lock on the door of the radiation room of a panoramic irradiator may not be deactivated by a powe…

4731.6140 DESIGN REQUIREMENTS. Subpart 1. Applicability. This part applies to irradiators whose construction began after July 1, 1993. Subp. 2. Panoramic irradiators. For panoramic irradiators, a licensee must: A. design shielding walls to meet generally accepted building code re…

4731.6150 CONSTRUCTION MONITORING AND ACCEPTANCE TESTING. Subpart 1. Applicability. This part applies to irradiators whose construction began after July 1, 1993. The requirements of this part must be met prior to loading sources. Subp. 2. Panoramic irradiators. For panoramic irra…

4731.6160 TRAINING. Subpart 1. Required instruction. Before an individual is permitted to operate an irradiator without a supervisor present, the individual must be instructed in: A. the fundamentals of radiation protection applied to irradiators, including: (1) the differences b…

4731.6170 OPERATING AND EMERGENCY PROCEDURES. Subpart 1. Operating procedures. A licensee must have and follow written operating procedures for: A. operation of the irradiator, including entering and leaving the radiation room; B. use of personnel dosimeters; C. surveying the shi…

4731.6180 PERSONNEL MONITORING. Subpart 1. Irradiator operators. Irradiator operators must wear a personnel dosimeter while operating a panoramic irradiator or while in the area around the pool of an underwater irradiator. The personnel dosimeter must be capable of detecting high…

4731.6190 RADIATION SURVEYS. Subpart 1. Panoramic irradiators. For panoramic irradiators, the following radiation surveys must be conducted: A. before the facility starts to operate, in the area outside the shielding of the radiation room, with the sources in the exposed position…

4731.6200 DETECTION OF LEAKING SOURCES. Subpart 1. Dry-source-storage sealed sources. Each dry-source-storage sealed source must be tested for leakage at intervals not to exceed six months using a leak test kit or method approved by the commissioner, the NRC, or an agreement stat…

4731.6210 INSPECTION AND MAINTENANCE. Subpart 1. Required checks. A licensee must perform inspection and maintenance checks that include, as a minimum, each of the following at the frequency specified in the license or license application: A. operability of each aspect of the acc…

4731.6220 POOL WATER PURITY. A. A pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water conductivity rises above 20 microsiemens per centimeter, a licen…

4731.6230 ATTENDANCE DURING OPERATION. A. An irradiator operator and at least one other individual who is trained in how to respond and prepared to promptly render or summon assistance if the access control alarm sounds must be present on site: (1) whenever the irradiator is oper…

4731.6240 ENTERING AND LEAVING THE RADIATION ROOM. Subpart 1. Entry. Upon first entering the radiation room of a panoramic irradiator after an irradiation, the irradiator operator must use a survey meter to determine that the source has returned to its fully shielded position. Th…

4731.6250 IRRADIATION OF EXPLOSIVE OR FLAMMABLE MATERIALS. A. Irradiation of explosive material is prohibited unless a licensee has received prior written authorization from the commissioner. Authorization shall not be granted unless the licensee can demonstrate that detonation o…

4731.6260 RECORDS AND RETENTION PERIODS. A licensee must maintain the following records at the irradiator for the periods specified: A. a copy of the license, license conditions, documents incorporated into a license by reference, and amendments thereto, until superseded by new d…

4731.6270 REPORTS. Subpart 1. Required reports. If not reported under other parts of this chapter, a licensee must report the following events: A. source stuck in an unshielded position; B. any fire or explosion in a radiation room; C. damage to the source racks; D. failure of th…

4731.7000 LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING. Subpart 1. Applicability. Parts 4731.7000 to 4731.7280 provide for the issuance of a license authorizing the use of licensed materials including sealed sources, radioactive tracers, radioactive markers, and ur…

4731.7010 APPLICATION. A person must file an application for a specific license authorizing the use of licensed material in well logging on an application for material license form prescribed by the commissioner. An application for a license, other than a license exempted from Co…

4731.7020 SPECIFIC LICENSE; WELL LOGGING. The commissioner shall approve an application for a specific license for the use of licensed material in well logging if the applicant: A. satisfies the general licensing requirements under parts 4731.0575 for special nuclear material, 47…

4731.7030 AGREEMENT WITH WELL OWNER OR OPERATOR. Subpart 1. Agreement required. A. A licensee may perform well logging with a sealed source only after the licensee has a written agreement with the employing well owner or operator. The written agreement must be kept for three year…

4731.7040 REQUEST FOR WRITTEN STATEMENTS. A license is issued with the condition that the licensee shall, at any time before expiration of the license, upon the commissioner's request, submit written statements, signed under oath or affirmation, to enable the commissioner to dete…

4731.7050 LABELS, SECURITY, AND TRANSPORTATION PRECAUTIONS. Subpart 1. Labeling. A. A licensee may not use a source, source holder, or logging tool that contains licensed material unless the smallest component that is transported as a separate piece of equipment with the licensed…

4731.7060 RADIATION DETECTION INSTRUMENTS. Subpart 1. Required survey instruments. A licensee must keep a calibrated and operable radiation survey instrument capable of detecting beta and gamma radiation at each field station and temporary job site to make the radiation surveys r…

4731.7070 LEAK TESTING; SEALED SOURCES. Subpart 1. Testing and record keeping requirements. A licensee that uses a sealed source must have the source periodically tested for leakage. The licensee must keep a record of leak test results in units of microcuries and retain the recor…

4731.7080 PHYSICAL INVENTORY. A. A licensee must conduct a semiannual physical inventory to account for all licensed material received and possessed under the license. The licensee must retain records of the inventory for three years from the date of the inventory for inspection …

4731.7090 RECORDS OF MATERIAL USE. Subpart 1. Use records. A licensee must maintain records for each use of licensed material showing: A. the make, model number, and a serial number or a description of each sealed source used; B. in the case of unsealed licensed material used for…

4731.7100 DESIGN AND PERFORMANCE CRITERIA FOR SOURCES. Subpart 1. General requirements. A licensee may only use sealed sources in well logging applications that: A. are doubly encapsulated; B. contain licensed material whose chemical and physical forms are as insoluble and nondis…

4731.7110 INSPECTION AND MAINTENANCE; OPENING SOURCE OR SOURCE HOLDER. Subpart 1. Checks before use. A. Before each use, a licensee must visually check source holders, logging tools, and source handling tools for defects to ensure that the equipment is in good working condition a…

4731.7120 SUBSURFACE TRACER STUDIES. A. A licensee must require all personnel handling radioactive tracer material to use protective gloves and, if required by the license, other protective clothing and equipment. The licensee must take precautions to avoid ingestion or inhalatio…

4731.7130 RADIOACTIVE MARKERS. A licensee may use radioactive markers in wells only if the individual markers contain quantities of licensed material not exceeding the quantities specified under part 4731.3145. The use of markers is subject only to the requirements of part 4731.7…

4731.7140 URANIUM SINKER BARS. A licensee may use a uranium sinker bar in well logging applications only if it is legibly impressed with the words "CAUTION: RADIOACTIVE-DEPLETED URANIUM. NOTIFY CIVIL AUTHORITIES (or company name) IF FOUND." Statutory Authority: MS s 144.1202; 144…

4731.7150 USE WITHOUT A SURFACE CASING. A licensee may use a sealed source in a well without a surface casing for protecting freshwater aquifers only if the licensee follows a procedure for reducing the probability of the source becoming lodged in the well. The procedure must be …

4731.7160 ENERGY COMPENSATION SOURCE. A. A licensee may use an energy compensation source (ECS) that is contained within a logging tool or other tool components only if the ECS contains quantities of licensed material not exceeding 100 microcuries (3.7 MBq). B. For well logging a…

4731.7170 TRITIUM NEUTRON GENERATOR TARGET SOURCE. A. Use of a tritium neutron generator target source, containing quantities not exceeding 30 curies (1,110 MBq) and in a well with a surface casing to protect freshwater aquifers, is subject to parts 4731.7000 to 4731.7270, except…

4731.7200 TRAINING. Subpart 1. Logging supervisor. A licensee must not permit an individual to act as a logging supervisor until the individual: A. completes training in the subjects under subpart 5; B. receives copies of and instruction in: (1) the applicable provisions of parts…

4731.7210 OPERATING AND EMERGENCY PROCEDURES. Subpart 1. Requirement. A licensee must develop and follow written operating and emergency procedures. Subp. 2. Operating and emergency procedures. A licensee's written operating and emergency procedures must address: A. the handling …

4731.7220 PERSONNEL MONITORING. A. A licensee may not permit an individual to act as a logging supervisor or logging assistant unless the individual wears a personnel dosimeter at all times during the handling of licensed radioactive materials. Each personnel dosimeter must be as…

4731.7230 RADIATION SURVEYS. Subpart 1. Requirement. A licensee must make radiation surveys, including but not limited to the surveys required under subpart 2, of each area where licensed materials are used and stored. Subp. 2. Safety surveys. A. Before transporting licensed mate…

4731.7240 RADIOACTIVE CONTAMINATION CONTROL. A. If a licensee detects evidence that a sealed source has ruptured or licensed materials have caused contamination, the licensee must immediately initiate the emergency procedures required under part 4731.7210. B. If contamination res…

4731.7250 SECURITY. A. A logging supervisor must be physically present at a temporary job site whenever licensed materials are being handled or are not stored and locked in a vehicle or storage place. The logging supervisor may leave the job site to obtain assistance if a source …

4731.7260 DOCUMENTS AND RECORDS; FIELD STATIONS. A licensee must maintain the following documents and records at a field station: A. a copy of parts 4731.1000 to 4731.2950 and 4731.7000 to 4731.7280; B. the license authorizing the use of licensed material; C. the operating and em…

4731.7270 DOCUMENTS AND RECORDS; TEMPORARY JOB SITES. A licensee conducting operations at a temporary job site must maintain the following documents and records at the temporary job site until the well logging operation is completed: A. the operating and emergency procedures requ…

4731.7280 NOTIFICATION OF INCIDENTS AND LOST SOURCES; ABANDONMENT PROCEDURES. Subpart 1. Notification; ruptured source. A licensee must immediately notify the commissioner by telephone according to part 4731.0200, subpart 5, and subsequently, within 30 days, by confirmatory lette…

4731.8000 PHYSICAL PROTECTION OF CATEGORY 1 OR CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL. A. Parts 4731.8010 to 4731.8090 apply to any person who, under the regulations in this chapter, possesses or uses at any site, an aggregated category 1 or category 2 quantity of radioact…

4731.8005 EXEMPTION FOR WASTE. A licensee that possesses radioactive waste that contains category 1 or category 2 quantities of radioactive material is exempt from the requirements of parts 4731.8010 to 4731.8125. Except that any radioactive waste that contains discrete sources, …

4731.8010 PERSONNEL ACCESS AUTHORIZATION REQUIREMENTS FOR CATEGORY 1 OR CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL. Subpart 1. General. A. Each licensee that possesses an aggregated quantity of radioactive material at or above the category 2 threshold must establish, implement…