16 Del. Admin. Code § 4465-H-6.0

Current through Register Vol. 28, No. 7, January 1, 2025

Section 4465-H-6.0 - General Regulatory Provisions

6.1 Unless otherwise provided in this Part, this Section applies to all Radiation Generating Devices (RGDs). Certified and Certifiable Cabinet X-ray Systems as defined in this Part shall also meet the requirements of 21 CFR 1020.40.

6.2 Warning Devices.

6.2.1 Warning devices shall be labeled so that their purpose is easily identified.

6.2.2 An easily visible warning device light labeled with the words "X-RAY ON," or words having a similar intent, shall be located a) near any switch that energizes an x-ray tube or b) in a conspicuous location near the radiation source housing and radiation beam and visible from all instrument access areas and shall be illuminated only when the tube is energized. This warning light shall be of a fail-safe design.

6.3 Labeling.

6.3.1 All RGD equipment shall be labeled with a readily visible and discernible sign or signs bearing the radiation symbol (defined in Part D.901 of these regulations) and the words: "CAUTION RADIATION - THIS EQUIPMENT PRODUCES RADIATION WHEN ENERGIZED," or words having a similar intent, near any switch that energizes an x-ray tube.

6.3.2 For RGDs with designed openings, for object entries (such as baggage units), the following shall be posted at or near each opening: "CAUTION - X-RAY HAZARD: DO NOT INSERT ANY PART OF THE BODY WHEN SYSTEM IS ENERGIZED", or words having similar intent.

6.4 Radiation Source Housing. Each x-ray tube housing shall be subject to the following requirements:

6.4.1 Interlock. When the x-ray tube housing is the primary shielding for the x-ray tube, and is intended to be opened for normal use or maintenance, the housing shall be equipped with an interlock that shuts off the high voltage to the x-ray tube if the housing is opened; and

6.4.2 Radiation Emission Limit. Each x-ray tube housing shall be so constructed that, with all shutters closed, the leakage radiation measured at a distance of 5 centimeters from the x-ray tube housing surface does not exceed 0.025 millisieverts (mSv), or 2.5 milliRem (mRem) per hour. This limit shall be met at the maximum tube rating. For closed-beam systems, this requirement can be met by complying with Part H, subsection 7.4, Radiation Emission Limit. For a RGD in a shielded room, this limit can be met by measuring from any accessible surface outside the room housing the RGD. For hand-held, open-beam RGDs, this requirement can be met by complying with the limits in Part H, subsection 9.3, Radiation Emission Limit.

6.5 Generator Cabinet or High Voltage Source Radiation Emission Limits. Each x-ray generator or high-voltage source shall be supplied with a protective cabinet which limits leakage radiation to 0.025 millisieverts (mSv), or 2.5 milliRem (mRem) per hour at a distance of 5 centimeters measured at the nearest accessible surface. For closed-beam systems, this requirement can be met by complying with subsection 7.1.4. Radiation Emission Limit. For a RGD in a shielded room with the high-voltage generator also inside the shielded room, this limit can be met by measuring from any accessible surface outside the room housing the RGD. For hand-held, open-beam RGDs, this requirement can be met by complying with the limits in Part H, subsection 9.3, Radiation Emission Limit.

6.6 Surveys.

6.6.1 Radiation surveys of all RGDs shall be sufficient to show compliance with radiation emission requirements of this Part, and as required by Part D, Section 6.0 (Occupational Dose Limits for Adults) and Part D, Section 13.0 (Dose Limits for Individual Members of the Public) of these regulations. The radiation surveys shall be sufficient to evaluate the magnitude and extent of radiation emissions and the potential radiological hazards that could be present. At a minimum, surveys shall be performed:

6.6.1.1 Upon installation of the equipment, and at least annually thereafter;

6.6.1.2 Following any change in the initial arrangement, number, or type of local components in the system;

6.6.1.3 Following any maintenance requiring the disassembly, removal, or repair of a local component in the system;

6.6.1.4 During the performance of maintenance, calibration and other procedures if the procedures require the presence of a primary x-ray beam while any local component in the system is disassembled or removed;

6.6.1.5 Post bypass of a safety device or interlock as required by Part H, subsection 6.6.7.2;

6.6.1.6 Any time a visual inspection of the local components in the system reveals an abnormal condition;

6.6.1.7 Whenever a personnel monitoring device shows a significant increase over previous monitoring period or readings are approaching the limits specified in Part D, Section 6.0 (Occupational Dose Limits for Adults) of these regulations.

6.6.2 The registrant shall have access to sufficiently calibrated, appropriate and operable radiation survey instruments to make physical radiation surveys as required by this Part. The instruments shall be capable of detecting and measuring the types and levels of radiation involved (including primary, scattered, and leakage radiation).

6.6.3 The registrant shall assure the maintenance and calibration of all monitoring and survey instruments per Part D, subsection 16.2 of these regulations.

6.6.4 Radiation survey measurements shall not be required if a registrant can otherwise demonstrate compliance with the requirements of this Part to the satisfaction of the Agency.

6.6.5 Posting. Each area or room containing an RGD where an individual may receive 0.02 millisieverts (mSv), or 2 milliRem (mRem) in any one hour or 1 millisieverts (mSv), or 100 milliRem (mRem) per year shall be conspicuously posted with a sign or signs bearing the radiation symbol (as defined in Part D, Section 28.0 of these regulations) and the words "CAUTION - X-RAY EQUIPMENT," "CAUTION - RADIATION GENERATING DEVICE" or words having a similar intent.

6.6.6 Security. RGDs shall be secured in such a way as to be accessible to, and operated by only authorized and trained personnel.

6.6.7 Operating Requirements.

6.6.7.1 Procedures. Normal operating procedures shall be written and available to all RGD workers. No individual shall be permitted to operate a RGD in any manner other than that specified in the procedures unless such individual has obtained the written approval of the radiation safety officer.

6.6.7.2 Bypassing.

6.6.7.2.1 No individual shall bypass a safety device, interlock, or remove shielding unless such individual has obtained the written approval of the radiation safety officer. Such approval shall be for a specified period of time.

6.6.7.2.2 When a safety device or interlock has been bypassed, a readily discernible sign bearing the words "SAFETY DEVICE NOT WORKING," or words having a similar intent, shall be placed on the radiation source housing and at the control switch.

6.6.7.2.3 A record of any bypass of a safety device or interlock shall be maintained; the record shall contain such information as the date the alteration was made, type of alteration, length of time the unit remained in the altered condition, post bypass survey and signed by the RSO, individual who made the alteration, and the individual who restored the unit to original condition.

6.6.7.3 Control Panel.

6.6.7.3.1 The RGD can only be activated from a control panel.

6.6.7.3.2 All indicators and controls that control the primary beam shall be identifiable and discernible through the use of labels, symbols, software displays or the equivalent.

6.6.7.4 Interlocks.

6.6.7.4.1 An interlock shall not be used to de-activate the x-ray tube or RGD, except in an emergency or during testing of the interlock system.

6.6.7.4.2 After triggering any interlock, it shall be possible to reset the RGD to full operation only from a control panel.

6.6.7.4.3 All interlocks shall be of a fail-safe design.

6.6.7.5 Multiple Sources. If more than one x-ray tube assembly(s) or focal spot can be operated sequentially or simultaneously from a control panel, visual indicators shall identify which tube assembly(s) or focal spot has been selected. The selectors shall be identified as to their function. If a letter or number is used, a reference card or table explaining the code shall be affixed to the control panel.

6.6.8 Repair or Modification of X-Ray Tube or RGD Systems. Only trained internal personnel authorized by the registrant's senior management, or state-registered Radiation Service Providers shall be permitted to install, repair, or make modifications to the RGD. No operation involving removal of covers, shielding materials or tube housings or modifications to shutters, collimators, or beam stops shall be performed without ascertaining that the tube is off and will remain off until safe conditions have been restored. The main power switch with a lock-out / tag-out, rather than interlocks, shall be used for routine shutdown in preparation for repairs. It is the responsibility of the registrant to assure that qualified personnel install, repair, or make modifications to the RGD.

6.6.9 Testing of Safety Devices.

6.6.9.1 Tests of all safety devices, such as interlocks, shutters, warning lights, and required emergency shut-off switches shall be conducted at intervals not to exceed 12 months on all operable RGDs.

6.6.9.2 If any safety device fails during testing, the RGD shall be removed from service until the safety device failure is corrected or proper temporary administrative controls established and approved in writing by the RSO.

6.6.9.3 Records of safety device tests, check dates, findings and corrective actions shall be available for inspection and maintained for 5 years.

6.6.9.4 Records shall include the date of the test, a list of the safety devices tested, survey instrument information, calibration date, the results of the test, the name of the person performing the tests and corrective actions taken for safety devices that fail the required test.

6.6.9.5 Testing of safety devices may be deferred if the unit and/or installation is clearly marked and kept out of service; units and/or installations brought back into service after exceeding the 12 month interval shall be tested prior to use.

6.6.9.6 If testing of a safety device cannot be performed due to manufacturer design, the registrant shall document that the safety device will not be tested and specifically why the safety device cannot be tested.

6.6.10 Instruction and Training. The registrant shall document the scope of training required for the RGD they possess in accordance with this section. No individual shall be permitted to operate or maintain an RGD, or enter a shielded room without appropriate instruction and training. Records shall be maintained onsite of all required training and instruction, and made available for review by the Agency. Each such individual shall receive instruction in and demonstrated competence as to:

6.6.10.1 Types of radiation and identification of radiation hazards associated with the use of the RGD and associated equipment and precautions or measures necessary to minimize radiation exposure;

6.6.10.2 Significance of the various radiation warning, safety devices, and interlocks incorporated into the equipment, or the reasons they have not been installed on certain pieces of equipment and the extra precautions required in such cases;

6.6.10.3 Commensurate with potential hazards of use, biological effects of radiation, radiation risks, and recognition of symptoms of an acute localized exposure;

6.6.10.4 Normal operating procedures for each type of RGD and associated equipment, including having received hands-on training, and procedures to prevent unauthorized use;

6.6.10.5 Procedures for reporting an actual or suspected accidental exposure or other radiation safety concerns, such as any unusual occurrence or malfunction that may involve exposure to radiation; and

6.6.10.6 Performing surveys where applicable.

6.6.11 Radiation Protection Responsibility.

6.6.11.1 The registrant's senior management shall make the ultimate decision to use any Radiation Generating Devices (RGD), and be ultimately responsible for radiation safety.

6.6.11.2 The registrant's senior management shall designate an individual responsible for radiation safety, or a Radiation Safety Officer (RSO). This individual shall have direct access to senior management for radiation safety issues. This individual shall have training and experience commensurate with the scope of the radiation safety program to carry out the responsibilities as indicated below.

6.6.11.2.1 Establishing and overseeing operating and safety procedures that maintain radiation exposures as low as reasonably achievable (ALARA), and to review them periodically to ensure that the procedures are current and conform with these regulations;

6.6.11.2.2 Ensuring that individual monitoring devices are properly used by occupationally exposed personnel as required by the regulations, that records are kept of the monitoring results, and that timely notifications are made as required by Part D;

6.6.11.2.3 Investigating and reporting to the agency each known or suspected case of radiation exposure to an individual or radiation level detected in excess of limits established by these regulations and each theft or loss of source(s) of radiation, determining the cause, and taking steps to prevent its recurrence;

6.6.11.2.4 Having a thorough knowledge of management policies, administrative procedures and records of the registration permit-holder and keeping management informed on a periodic basis of the performance of the registrant's radiation protection program, if applicable;

6.6.11.2.5 Assuming control and having the authority to institute corrective actions including shutdown of operations when necessary in emergency situations or unsafe conditions;

6.6.11.2.6 Maintaining records as required by these regulations; and

6.6.11.2.7 Ensuring that personnel are adequately trained and complying with these regulations, the conditions of the certificate of registration, and the operating and safety procedures of the registered permit-holder.

6.6.11.2.8 Ensuring that safety devices, interlocks, warning signals, labels, postings, and signs are functioning and located where required.

16 Del. Admin. Code § 4465-H-6.0

23 DE Reg. 306( 10/1/2019) (final)