7. Procedures for Work with Radiation Producing Machines

• Notify the RSO before bringing an RPM onto campus. The RSO must register most machines with the CDPH within 30 days. However, in the case of machines with an operating potential of greater than 500kVp or which are capable of producing a significant radiation hazard, UC Berkeley must notify the CDPH at least 60 days before taking possession of the machine or before starting construction or reconstruction of the room where the machine will be housed (whichever comes first.)
• Apply for an RUA before acquiring or operating the machine, regardless of the means of acquisition (purchase, lease, gift, loan, “in-house” fabrication) and regardless of ownership.
• All individuals must complete the RPM Safety Training to be listed on an RUA. Electron Microscope users are the exception and they do not require RPM training or to be listed on the RUA. They only require machine-specific training by the RH or Lab Contact. The Electron Microscope RH and Lab Contact are required to have RPM training.
• Notify the RSO before removing an RPM from campus. The RSO must notify the CDPH within 30 days.
• Notify the RSO if you deactivate an RPM or render it incapable of producing radiation. The RSO must notify the CDPH within 30 days. Label machines that are deactivated but left on campus with the words:

DEACTIVATED RADIATION PRODUCING MACHINE

Do Not Move or Operate or Reactivate Without Notifying EH&S Radiation Safety.

CALL (510) 642-3073

• Operate RPMs in accordance with a valid RUA. Among other items, the RUA lists the RH and other users and describes the machine, operating parameters, procedures, locations, dosimetry, and safety precautions to be used.
• Immediately notify the RSO of intended changes in personnel, machine location, machine repair, operating parameters, or other items in the RUA.
• Do not bypass safety interlocks except as specified on the approved RUA SOP (usually for test and/or alignment purposes). Record authorized bypass operations in the “Use Log”.
• Notify the RSO immediately if any safety interlocks fail to operate as intended or if you suspect an accidental exposure.

• Each RPM is controlled by an RH, who is responsible for ensuring compliance with applicable rules and procedures by all operators.
• The RH and users must have adequate knowledge to ensure safe operation and RUA compliance with the RSM.
• Operators of cabinet x-ray machines and portable units meeting the definition of industrial x-ray machines must pass written examinations addressing operation, safety, and emergency procedures.
• Machines may only be used by, or under the direct supervision of, an approved operator listed on the RUA.
• A qualified authorized repair person may operate a machine during setup, testing, and repair, and does not need to be on the RUA. If there is any question as to the work to be done or the qualifications of the repairperson, contact the campus RSO.

PPE should be used when it will effectively protect parts of the body that may be exposed to X-rays. In general, PPE such as leaded aprons, gloves, and/or goggles are useful only for low-energy (<100 kVp) X-ray sources. PPE does not substitute for required engineering controls.

As a general safety precaution, locate an RPM in a dedicated room or in an area that can be controlled and secured, away from high-occupancy areas.

Observe the following precautions when installing or relocating an RPM:

• Intercept primary beams by use of a primary barrier (unless the beams are confined or limited by other means).
• Locate RPMs in controlled areas so that personnel are not irradiated.
• Control scatter/secondary radiation to reduce radiation exposure.
• Obtain prior approval from the RSO for any change in location of an RPM (unless the RUA specifies otherwise, this requirement applies to portable as well as other RPMs.)
• Rooms containing RPMs must be locked or under the control of RUA personnel such that measures can be effectively taken to prevent the unauthorized use or removal of the RPM. If non-RUA authorized users are permitted to be in the room, then the RPM must be either under constant surveillance by RUA personnel or locked such that it cannot be used, operated, or removed by an unauthorized individual.

• Each machine must clearly display a valid RUA or a posting noting where a copy of the RUA can be found.
• Each machine must be clearly and visibly labeled to caution individuals that radiation is produced during operation.
• “Radiation Area” or “High Radiation Area” must be posted as required.
• A copy of the UC Berkeley “Radiation Producing Machine Emergency Procedures” must be posted in the immediate vicinity of each machine.

EH&S conducts surveys of every campus RPM as follows:

• Before routine use starts
• Following any major changes in configuration or repair
• Routine surveys including testing for radiation leakage and power/shutter status indicators are done over a range of time periods based on the hazard associated with the machine and use. The specific survey frequency for each RPM is noted in the RUA. All RPMs shall be surveyed at minimum annually. The typical survey frequency range for the different class RPMs is as follows:
  • Class 1 RPM - annually to semi-annually
  • Class 2 RPM - semi-annually to quarterly
  • Class 3 RPM - quarterly to monthly

The required documentation on surveys and tests are specified in the RUA.

The RSO or RSO-designated EH&S staff does the following:

• Reviews all campus building plans that include RPMs.
• Inspects new or modified RPMs or facilities before operation starts, to determine their safety for the intended use and their compliance with federal, state, local, and campus regulations.
• Performs frequent inspections to ensure the machines’ ongoing safety and compliance including verification of interlocks, when required.

Most Class 2 and 3 machines may require the use of dosimetry. The dosimeters are issued by EH&S and must be worn as specified by the RUA. Dosimetry is not normally required for personnel whose radiation-related duties are limited to working around electron microscopes, X-ray fluorescence units, and other self-contained low-"current/potential" machines. The RSO will determine when dosimetry is required.

Federal, state, and local regulations for radiation producing machines require that they be equipped with certain safety devices. These typically include a fail-safe warning light, fail-safe interlocks, beam enclosures, and shielding. In addition, a radiation survey meter may be needed.

The following procedures apply to all RPMs:

• Safety devices must be in working order before the machine is operated.
• Only authorized repair persons may operate an RPM without using specified, operable shielding and other safety devices.
• Any changes to these safety devices must be reviewed by the RSO. Do not replace or modify safety devices without pre-approval.
• No safety device is absolutely fail-safe or foolproof. Interlocks, like those on the door of a cabinet x-ray unit, should not be relied on to automatically close the beam shutter. If an interlock is used to secure a beam, a radiation survey should be performed each time to verify the absence of radiation before placing a part of the body where the beam (or scatter from the beam) might be expected.
• Safety devices must not be purposely defeated, even when their use makes operating the machine difficult or impossible. If the design of a safety device prevents or inhibits operation, the RSO may approve an alternate safety device or method of equal protective value. (If safety devices are modified, it may be necessary to modify existing operating procedures or the RUA, and to retrain operators.)
• Do not operate a machine if a required safety device fails. Do not use the unit until it has been repaired and then checked by EH&S.
• Immediately notify EH&S if an unexpected personnel radiation exposure occurs or is suspected to have occurred. Any overexposed dosimeter is considered presumptive evidence of exposure to the individual to whom the dosimeter was assigned.

An SOP for each RPM must be established that describes in adequate detail how the machine is used and all safety measures that must be observed. Each user of an RPM must read the unit-specific SOP.

Maintain a “Use Log” for all RPMs. This log can be helpful when investigating incidents and/or determining a machine’s operating status and reliability. At minimum, the Use Log must note the following information each time the machine is used:

• Date of use
• Name of the operator(s) and RH if more than one RUA/person is using this machine
• Description of use
• Beam voltage
• Beam current
• Time beam turned on
• Time beam turned off
• Operational abnormalities, repairs, etc.

The RH is responsible for the ongoing custody and security of any RPM listed on the RUA. Any loss or potential loss of an RPM must be reported to EH&S at (510) 642-3073 as soon as possible after the loss is suspected.

Rooms containing an RPM must be locked or under the control of RUA personnel such that measures can be effectively taken to prevent the unauthorized use or removal of the RPM. If non-RUA authorized users are permitted to be in the room where the RPM is present, the RPM must be either under constant surveillance by RUA personnel or locked such that it cannot be used, operated, or removed by an unauthorized individual.

The requirements in this section cover a range of radiation producing machines commonly used on campus. Be sure to identify and meet the listed conditions that pertain to the RPM(s) covered by your RUA.

7.14.1. Electron Microscopes

• Valid and current RUA with operator name
• Training
• Operating log
• Adherence to RUA requirements
• Notification to EH&S of any changes to use, machine, personnel, or protocol.

7.14.2. Diagnostic Medical Machines

• Valid and current RUA with operator name
• Posting of CDPH certificate
• Training
• Operating log
• Dosimetry, as assigned
• Adherence to RUA requirements
• Notification to EH&S of any changes to use, machine, personnel, or protocol
• Regular documented service

Note: All human-use machine operations, installation designs, etc., must be in accordance with published CDPH regulations and the recommendations of the National Council of Radiation Protection (NCRP) EH&S provides oversight of these operations, installation designs, etc. to make sure this requirement is met.

7.14.3. Cabinet X-ray Machines

• Valid and current RUA with operator name
• All operators must pass the RPM Safety Training and practical examination for that machine
• Operating log
• Dosimetry, as assigned
• Adherence to RUA requirements
• Enclosure. These units must use shielded boxes or be used in shielded rooms such that (1) no radiation levels outside the shield exceed 2 mrem per hour, (2) no person is within the shield at any time while the machine is producing X-rays, and (3) all shield entrances are interlocked in some manner so that any attempt to enter will shut off the machine.
• X-ray indicator(s). Each unit must have a conspicuous fail-safe warning light or device that indicates whether the X-ray tube is energized. The light must be placed near the X-ray tube assembly and labeled “X-ray on.”
• Safety-device approval. All interlocks, indicators, and other safety devices must be checked and approved by the RSO or RSO-designated EH&S staff prior to use.
• Survey. The RUA indicates if any surveys are required, and the required schedule.
• Notification to EH&S Radiation Safety of any changes to use, machine, personnel, or protocol.
• Interlocks shall be annually tested to ensure they function as designed and the results documented. Failure of any interlock to function must be documented, reported to the RSO, and power to the machine locked out until repairs are made and the RSO inspects the effectiveness of corrective actions.

7.14.4. X-ray Diffraction and Fluorescence Analysis Machines

• Valid and current RUA with operator name
• Training
• Operating log
• Dosimetry, as assigned
• Adherence to RUA requirements
• Procedures and records: Normal operating and alignment procedures are to be documented and readily available.
• Beam stop. Each port must have a beam stop that limits the dose rate immediately behind it to less than 2 mrem per hour at maximum settings.
• Locks. Secure unused ports with key-operated power switches so that the key cannot be removed during operation. Do not leave the key in the port lock when the machine is not in operation.
• X-ray indicator(s). Each machine must have a conspicuous fail-safe warning light or device that indicates whether the X-ray tube is energized. The light must be placed near the X-ray tube assembly and labeled “X-ray on”.
• Safety-device approval. All interlocks, indicators, and other safety devices must be checked and approved by the RSO prior to use.
• Beam enclosure. During routine operation, the primary beam path must be enclosed in a chamber that cannot be entered by any part of the body. The enclosure should be interlocked with the tube high-voltage supply or shutter so that the beam cannot be available unless the enclosure is in place.
• Shutter interlock. If an interlocked beam enclosure is not used, each port’s beam shutter must be interlocked with the accessory apparatus coupling or collimator so that the port can only open if the accessory is in place.
• “Shutter open” indicator. If an interlocked beam enclosure is not used, each port must be provided with a fail-safe “shutter open” indicator.
• Allowable radiation levels. The radiation level outside a beam enclosure typically is limited so that dose is 2 mrem per hour or less.
• Survey instrument. An operable radiation-survey instrument must be easily accessible for use with each machine at all times. This instrument must be used to monitor each initial setup and each significant modification thereof for excessive leakage, unsuspected beams, and other hazardous radiation conditions.
• Notification to EH&S Radiation Safety of any changes to use, machine, personnel, or protocol.
• Interlocks shall be annually tested to ensure they function as designed and the results documented. Failure of any interlock to function must be documented, reported to the RSO, and power to the machine locked out until repairs are made and the RSO inspects the effectiveness of corrective actions.

7.14.5. Field Radiography

Special controls are required for field radiography (as stated in 17 CCR§30336.1.)

7.14.6. Miscellaneous Machines

Any machine that does not fall into the categories above is considered a miscellaneous machine. Particle accelerators, demonstration Crookes tubes, and high-voltage supplies are examples of miscellaneous machines. Specific regulations for such machines are listed on the RUA, and may be similar to those required for the other machine categories.