16 Del. Admin. Code § 4465-H-8.0

Current through Register Vol. 28, No. 7, January 1, 2025
Section 4465-H-8.0 - Additional Requirements for Open Beam RGDs
8.1 In addition to the requirements in Part H, Section 6.0, the following requirements apply to all open beam RGDs not otherwise addressed in this Part.
8.2 Safety Device.
8.2.1 The registrant shall document their justification of the use of open-beam instead of closed-beam systems.
8.2.2 If the registrant needs to use an open-beam system, the registrant shall consider a safety device which prevents the entry of any portion of the operator's body into the path of the primary beam or which causes the primary beam to be shut off upon entry into its path.
8.2.3 If the registrant's use of the open-beam RGD does not permit the use of a safety device to prevent direct body exposure, the registrant shall maintain a written record of a description of the various safety devices that have been evaluated and reasons for why these devices cannot be used. These records shall be available onsite for inspection.
8.2.4 In lieu of the safety device described in section Part H, subsection 8.2 above, the registrant shall employ alternative methods (such as policies and procedures) to minimize the possibility of unnecessary exposure. These alternative methods shall be documented. The documentation shall include information about the absence of safety devices. This documentation shall be available for inspection as long as these methods are employed, plus an additional 5 years.
8.2.5 For portable open-beam RGDs that are manufactured to be used hand-held, or potentially used as a hand-held, without such safety devices, this safety device requirement may be met by complying with all the requirements in Part H, Section 9.0, Additional Requirements for Open-beam, Hand-held RGDs prior to use.
8.3 X-ray On Status. For open beam equipment, RGDs shall be provided with a readily discernible and active indication of:
8.3.1 X-ray tube "on-off" status located near the radiation source housing. The warning lights as required by Part H, subsection 6.2.2 can meet this requirement if the warning lights are readily discernible and viewable by anyone near the primary beam;
8.3.2 Shutter "open-closed" status located at the control panel and near each beam port on the radiation source housing, if the primary beam is controlled with a shutter. The shutter status device shall be clearly labeled as to the meaning of the status device (i.e., whether the shutter is open or closed). The status light at the control panel can meet the requirement for the status light at the beam port if the status light at the control panel is readily discernible and viewable by anyone near the primary beam; and
8.3.3 The x-ray tube "on-off" status indicator and the shutter "open-closed" status indicators shall be of a fail-safe design.
8.4 Labeling. Each unit will be labeled at or near the x-ray exit beam port to identify the location of the beam with the words, "CAUTION - X-RAY BEAM", "CAUTION - HIGH INTENSITY X-RAY BEAM", or words having a similar intent.
8.5 Beam Ports. Unused beam ports on radiation source housings shall be secured in the closed position in a manner which will prevent inadvertent opening.
8.6 Shutters. On open-beam RGD configurations that are designed to accommodate interchangeable components, each beam port on the radiation source housing shall be equipped with a shutter that cannot be opened unless a collimator or a component coupling has been connected to the beam port.
8.7 Radiation Emission Limits. The local components of an open-beam RGD shall be located and arranged and shall include sufficient shielding or access control such that no radiation emissions exist (exclusive of the primary beam) in any area surrounding the local component group which could result in a dose to an individual present therein in excess of the dose limits as outlined in Part D, Section 13.0 (Dose Limits for Individual Members of the Public) of these regulations. These emissions shall be met at any specified tube rating.
8.8 Primary Beam Attenuation. In cases where the primary x-ray beam is not intercepted by the detector device under all conditions of operation, protective measures shall be provided, such as auxiliary shielding or administrative procedures, to avoid exposure to any individual from the transmitted primary x-ray beam.
8.9 Operator Attendance. The operator shall be in immediate attendance at all times when the equipment is in operation except when the area is locked or the equipment is secured to protect against unauthorized or accidental entry.
8.10 Control of Access. If the RGD is not in a restricted area (as defined in Part A of these regulations), the operator shall be able to control access to the RGD at all times during operation. If the RGD is not in a restricted area (as defined in Part A) and the RGD is capable of creating a radiation area or a high radiation area (as defined Part A), the operator shall be able to control access to the RGD at all times during operation, and:
8.10.1 Radiation areas shall be conspicuously identified. The radiation source shall be within a conspicuous perimeter (e.g., rope, tape, or other barrier) that identifies the area in which the dose equivalent exceeds 0.05 millisieverts (mSv), or 5 milliRem (mRem) in one hour. The area described by the temporary barricade shall be suitably posted with "CAUTION -RADIATION AREA" signs. The operator shall ensure that no one is inside or enters the radiation area during operation of the RGD;
8.10.2 High radiation areas shall be conspicuously identified. The radiation source shall be within a conspicuous perimeter (e.g., rope, tape, or other barrier) that identifies the area in which the dose equivalent exceeds 1 millisieverts (mSv), or 100 milliRem (mRem) in one hour. The area described by the temporary barricade shall be suitably posted with "CAUTION - HIGH RADIATION AREA" signs. The operator shall ensure that no one is inside or enters the high radiation area during operation of the RGD;
8.10.3 The operator shall perform a visual check of the controlled area to ensure it is free of all unauthorized personnel immediately prior to activating or exposing the radiation source;
8.10.4 Surveillance of the exposure area shall be maintained during operation, either by visual or by other reliable means to ensure that no person enters the area;
8.10.5 With the exception of hand-held x-ray systems, following the conclusion of an exposure, the operator shall use a suitable calibrated and operable radiation detection instrument to verify that the radiation source is in its fully shielded condition or that the x-ray tube has been de-energized; or,
8.10.6 A personal alarming dose rate meter may be worn to approach the work area if the device is appropriately designed and calibrated for the type of x-ray emitted (i.e., pulse or continuous), set at an appropriate level to detect the presence of the source, for example 0.02 millisieverts (mSv), or 2 milliRem (mRem) per hour, and has been source-checked prior to use. The radiation in the work area must be reasonably uniform so that the device responds to radiation exposure to any part of the body. It may not be used to measure radiation levels, nor may it be used to indicate the presence of the source for potential non-uniform exposure, such as may occur during machine maintenance or work in a RGD target area;
8.10.7 Measurement of radiation levels for a radiation survey shall be performed using an appropriate calibrated radiation survey meter (see Part D, subsections 16.2 and 17.1). A radiation survey meter shall also be used when there is potential for non-uniform exposure to personnel, such as may occur during machine maintenance or work in a RGD target area;
8.10.8 During the initial exposure, the radiation levels shall be measured around the perimeter of the controlled area. The perimeter shall be adjusted accordingly to meet the access control requirement for radiation areas or high radiation areas; and;
8.10.9 The survey around the perimeter shall be made for each new operating condition and the perimeter adjusted accordingly. The area of operation shall be monitored periodically if radiation levels are variable.
8.10.10 Instruction and Training. In addition to the requirements in Part H, Section 6.0, no individual shall be permitted to operate or maintain an open-beam RGD unless such individual has received more specific and detailed instruction in and documented, demonstrated competence as to:
8.10.10.1 Sources and magnitude of common radiation exposure;
8.10.10.2 Units of radiation measurement;
8.10.10.3 Radiation protection concepts of time, distance, shielding, and ALARA;
8.10.10.4 Procedures and rights of a declared pregnancy;
8.10.10.5 Regulatory requirements and area postings;
8.10.10.6 Worker, embryo/fetus, and public dose limits;
8.10.10.7 Proper use of survey instruments and dosimetry; and
8.10.10.8 The policies and procedures required by Part H, subsection 6.6.
8.10.11 Personnel Monitoring. In addition to the requirements of Part D, Section 6.0 of these regulations (Occupational Dose Limits for Adults), extremity dosimetry shall be provided and used by:
8.10.11.1 Personnel working with or routinely working near and having potential for exposure to, the primary beam of an open-beam RGD; and
8.10.11.2 Personnel maintaining RGDs if the maintenance procedures require the presence of a primary radiation beam when any local component in the RGD is disassembled or removed.

16 Del. Admin. Code § 4465-H-8.0

22 DE Reg. 401( 11/1/2018) (Final)