Washington State University
SAFETY POLICIES AND PROCEDURES MANUAL

RADIATION SAFETY
9.22
Revised 3-02
Radiation Safety Office
335-8916

Radiation Machines

PDF link

OVERVIEW

The University regulates and supervises all activities associated with radiation machines in order to promote safety. (WAC 246-220, -221, -222, -224, -225, -227, -228, -229, and -254)

This section provides University regulations regarding the procurement, operation, maintenance and disposition of radiation machines.

Electron Microscopes

Electron microscopes, which are not covered by these safety regulations, must nonetheless be reported to the Radiation Safety Office (RSO) so that WSU can pay appropriate use fees to the Washington Department of Health.

Scope

These regulations apply to the use of all radiation machines located on University property (including all campuses or authorized field locations) and all radiation machines operated by University employees.

Authorization

Each WSU employee who seeks to use one or more radiation machines must obtain authorization from the Radiation Safety Committee by filing an Application to Use Radiation Machines and attached Radiation Machine Registration with the Radiation Safety Office. See the PDF forms 9.20.13-14 and 9.20.15.

The Radiation Safety Committee reviews and approves the procurement, registration, and utilization of all University radiation machines. Approval is considered on a case-by-case basis.

In its review, the committee considers the following:

Upon approval by the committee, the RSO issues a Radiation Machine Approval Sheet. See below.

PROCUREMENT

After approval by the RSO, authorized users may procure radiation machines by the following methods:

To purchase, submit a completed Departmental Requisition to Purchasing Services. See BPPM 70.10. NOTE: Do not use Department Orders or purchasing cards to procure radiation machines.

Prior Notification

Each individual who plans to procure a radiation machine must provide the Radiation Safety Office with the following data at least six weeks prior to scheduled arrival:

The individual must also file a completed Application to Use Radiation Machines and attached Radiation Machine Registration at the Radiation Safety Office at least two weeks in advance of the next Radiation Safety Committee meeting. See the PDF forms 9.20.13-14 and 9.20.15. The Radiation Safety Office may issue a temporary authorization to use the radiation machine(s).

Upon notification of intent to procure a radiation machine, the Radiation Safety Office conducts a preliminary safety check of the proposed location.

Radiation Safety Office Responsibilities

The Radiation Safety Office is responsible for notifying the Washington Department of Health within 30 days of receipt, transfer out of WSU, or disposal of any radiation machine. The Radiation Safety Office renews registration of all University radiation machines as required by the Department of Health (DoH).

University Inventory

The Radiation Safety Office records each radiation machine on the WSU inventory upon notification of arrival.

The Controller's Office inventories all University equipment with an acquisition cost of more than $5000. See BPPM 20.50.

Machine Location

Place the equipment in an area that is not in the main traffic pattern of the laboratory or near continuously occupied work areas. A room devoted solely to the radiation machine which may be locked when not in use or during unattended operation is desirable.

HAZARDS

Authorized users and operators are to be aware of hazards associated with the operation of radiation machines. See also below for more information about machine-specific hazard prevention.

Nonradiation Hazards

Nonradiation hazards which may be associated with radiation machines are primarily electrical or physical. The safety precautions below must be followed:

Contact Environmental Health and Safety for more assistance; telephone 335-3041.

Radiation Hazards

Typical radiographic (diagnostic) X-ray tubes and cabinets operated at 30-50 kVp or higher can generate dose rates of over 105 rem (103 sieverts) per minute.

Radiation skin damage can occur at doses as low as 500 rem (5 sieverts) and delayed effects can be caused by much lower doses. Exposure to the direct beam for even a fraction of a second can therefore cause serious injury.

DOSIMETRY

The Radiation Safety Office (RSO) requires dosimetry for operation of a radiation machine. All personnel must wear their dosimeters whenever they work with or near the operating radiation machine. See also 9.45.

EMERGENCIES

Immediately notify the Radiation Safety Office if above-normal radiation exposure is suspected.

Follow emergency procedures in 9.35.

If unusual circumstances occur, such as malfunctioning controls, indicator lights, or interlocks, inform the RSO and the manufacturer.

Carefully note and preserve procedures and machine parameters and configuration in order to permit recreation of the incident with radiation-measuring devices in place.

In the case of highly collimated beams, personnel dosimetry may not give an accurate account of maximum radiation dose to the affected area of the body. (Calculations may be required.) Extremity dosimetry, however, can give a good indication of whether or not an exposure to the beam occurred. It is therefore important to submit dosimetry to the Radiation Safety Office for immediate processing if any exposure is suspected. Prompt notification may prevent additional overexposures.

USING RADIATION MACHINES

General Requirements

Users of radiation machines must:

The Radiation Machine Approval Sheet lists the authorized user, describes the machine, and specifies conditions of use.

Written Procedures

All personnel are to be aware of specific safety requirements for the machines operated and campus radiation safety regulations included in this chapter (Chapter 9) of the Safety Policies and Procedures Manual and in the Radiation Safety Office programs.

To view the Radiation Safety Office programs, go to the Radiation Safety Office web site at:

http://www.rso.wsu.edu/

The authorized user is responsible for preparing and providing written operating procedures explaining the use of each radiation machine under his or her control in a given laboratory. A safe operational procedure is carefully prepared, making use of built-in safety devices and correct techniques.

The authorized user places the procedures in the laboratory in which the equipment is located. A copy of these written procedures must be on file in the Radiation Safety Office.

Assistance

Contact the Radiation Safety Office for explanation of regulations and advice regarding safety procedures.

Contact the machine manufacturer for warranty and machine-specific issues.

Use Record

Users must maintain a record (use log) of the use of each piece of equipment. The record (use log) must include:

The record must be available for inspection.

Operating Personnel

The authorized user is responsible for ensuring operator compliance with all applicable regulations.

Only an approved operator may use a radiation machine or directly supervise the use of each machine. Approval is contingent on the operator demonstrating adequate knowledge and ability for safe use of the machine.

The authorized user is required to maintain a detailed training log, which includes written certification by the authorized machine user that the individual is adequately trained.

An authorized repairman may operate a machine during setup, testing, and repair.

These records, logs, and associated documentation must be available for inspection at all times.

Radiation Exposures

Radiation dose limits listed in 9.45 apply to all personnel involved in radiation machine use.

Regardless of compliance with the above item, and in keeping with ALARA, no person may incur an unwarranted radiation dose. See 9.10.

Safety Devices

Other than by authorized repair personnel, a radiation machine must never be operated unless all required shielding and safety devices are in place and functioning properly.

Certain safety devices are required for each campus radiation machine. Examples are:

The function of a safety device is to act as a backup rather than a replacement for proper procedure or caution.

All users must:

If the design of a radiation machine makes a desired operation inconvenient or impossible, the Radiation Safety Office and the manufacturer of the radiation machine must approve and substitute another safety device providing the same degree of protection prior to operation.

If a required safety device becomes nonfunctional, users must not operate the machine until the safety device is repaired and checked by the manufacturer.

Diagnostic tube operators must wear lead aprons.

In some cases, lead shielding may be added to reduce scatter. Such material must be permanently mounted so as not to pose a drop hazard. In cases when very low energy X-rays are emitted, shielding may be made from lighter materials, e.g., Lucite. Radiation levels must be verified by the RSO.

Posting and Labeling

Clearly label all radiation machines, declaring that the machines are capable of generating radiation. The Radiation Safety Office (RSO) supplies appropriate labels.

Post "Emergency Procedures." Obtain copies of these procedures from the Radiation Protection Program Manual or the RSO.

Post a "Notice to Employees," Washington Department of Health form RHF-3. Obtain copies of the form from the Radiation Safety Office.

Post radiation areas, high radiation areas, and very high radiation areas as defined and required in 9.32.

Post a valid Radiation Machine Approval Sheet near each machine.

Radiation Surveys

Radiation Safety Office personnel survey each machine prior to the commencement of routine use.

Radiation Safety Office personnel inspect and survey each radiation machine at various time intervals.

Following any major changes in configuration or repairs Radiation Safety Office personnel must survey each machine before it may be used again.

Self-Monitoring

Radiation survey meters are required for use of some radiation machines. In such cases, the survey meter must be appropriate for the type of radiation encountered. Since most equipment emits low-energy X-rays, a thin window probe or a thin crystal NaI probe is appropriate. (Metal window probes do not respond to X-ray energies of less than 50 keV.) The probe should be small enough to fit into cramped areas without disturbing delicate machinery.

Special survey meters may be required for use with accelerators where high-intensity X-ray and neutron beams may be present.

The Radiation Safety Office must approve the purchase of survey meters in advance.

Survey meter users must:

MACHINE-SPECIFIC HAZARD PREVENTION

Analytical Radiation Machines

Hazard Discussion

X-ray diffraction, fluorescence, and crystallography machines usually put out a highly collimated and intense X-ray beam. The primary beam produces a high dose rate near the port.

After the beam strikes the sample, the diffracted beam may be scattered at any angle. Scatter of the primary beam off the sample holder or beam stop must be evaluated by the RSO.

Safety Precautions

Departments must take the following steps to safeguard against hazards in using analytical radiation machines:

Contact the Radiation Safety Office for more information.

Open Beam

Open-beam configuration is defined as a mode of operation of an analytical X-ray system in which an individual could accidentally place some part of his or her body into the primary beam during normal operation if no further safety devices are incorporated. (WAC 246-228-010)

A shielding evaluation is required for all open beams.

Beam Stop

Each port must have a beam stop in place which limits the dose rate immediately behind it to less than 5 mrem/hour (0.05 mSv/hour) at maximum settings.

Unused Ports

All unused ports must be secured in such a way that tools are required to open them.

X-ray Indicators

There must be a conspicuous failsafe light or device near the X-ray tube assembly, for the power switch, which indicates whether the tube is energized. This light or device is to be labeled "X-ray on."

Machine Security

Each machine should have a key-operated power switch. The lock should be constructed so that the key cannot be removed during operation.

Do not leave the key in the lock when the machine is not in operation.

A custodian of the key must be assigned the responsibility of controlling access for operation of the radiation machine.

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 or shutter so that the beam cannot be available unless the enclosure is in place.

Shutter Interlock

Provide each port with a beam shutter which is interlocked with the accessory apparatus coupling or collimator in such a way that the port will be open only if the coupling or collimator is in place. Departments must provide such a device if there is to be any operation without an interlocked beam enclosure.

Shutter Open Indicator

Provide each port with a shutter-open indicator of failsafe design. Departments must provide such indicators if there is to be any operation without an interlocked beam enclosure.

Source Housing Radiation Levels

The radiation level outside a beam enclosure with all shutters closed may not exceed 2.5 mrem (0.025 mSv) in any one hour at any specified tube rating, measured at a distance of 5 cm from the surface.

Survey Instrument

An appropriate portable radiation survey instrument must be easily accessible at all times to each particle accelerator while in use. Such instruments are not required for use with any other type of radiation machine.

Records of radiation surveys must be retained and made available for inspection.

Safety Device Approval

The functions of all interlocks, indicators, and other safety devices are to be checked and approved by the Radiation Safety Office prior to use.

Cabinet X-ray Machines

Hazard Discussion

A cabinet X-ray machine usually employs a wide beam of X-rays inside a shielded, interlocked box or room. Tube potentials of up to 150 kVp are used. Radiation levels inside may be very high. Leakage radiation is not normally a problem since the enclosure must severely limit outside radiation levels. Fail-safe indicators show when the X-rays are being produced and the entry door must be interlocked.

Safety Precautions

The safety precautions described below must be followed:

Enclosure

Use machines only in shielded boxes or rooms meeting the following requirements:

X-ray Indicators

Provide each machine with a conspicuous fail-safe warning light or device and/or a power switch which indicates whether the X-ray tube is energized. Place the device near the X-ray tube assembly and label as "X-ray on."

Safety Device Approval

The Radiation Safety Office must check and approve the function of all interlocks, indicators, and other safety devices for cabinet radiation machines prior to use.

Particle Accelerators

One category of radiation machines has the capability to produce high levels of radiation. This type of radiation machine is the particle accelerator.

Particle accelerators are regulated in accordance with the provisions of Chapter 246-229 of WAC.

REPAIR AND ALIGNMENT

Most severe injuries occur during nonroutine operations such as repair and alignment.

In general, only an authorized representative of the manufacturer of the radiation machine repairs the machine.

Do not perform any of the following operations without verifying that the tube is off and will remain off until safe conditions have been restored:

Turn off the main power switch prior to repairs. Do not rely on safety interlocks.

Do not operate an X-ray tube without a suitable housing to restrict the radiation to a well-defined beam.

Use alignment procedures recommended by the manufacturer of the specific X-ray system being utilized, if available.

Do not use customized or ad hoc alignment procedures unless approved by the manufacturer and the Radiation Safety Office.

Temporary Increase in Dose

If an alignment procedure may result in a temporary increase in the dose rate in an area, the person in charge must erect temporary barriers and warning signs as required, and the RSO must be notified in advance. RSO personnel can evaluate the anticipated dose rate increase. The area is to be kept under strict surveillance until normal operation is restored.

Assembly

Conduct repairs and assembly on an uncluttered surface. Any pieces that are left out during assembly will then be conspicuous.

After assembly, Radiation Safety Office personnel or other personnel authorized by the Radiation Safety Office must check the X-ray system or radiation machine. Give particular attention to the alignment of shielding, shutters, and collimators. Inspect lead parts for damage or distortion which could result in radiation leakage. Lead parts should be mounted in a manner that will prevent cold-flow caused by the weight of the parts.

It is also recommended that a new accessory not be aligned or operated until procedures have been reviewed and a radiation survey carried out.

DISPOSITION

No radiation machine may be removed from campus or deactivated without prior approval of the Radiation Safety Office (RSO).

See below for the detailed policy on the surplus and/or transfer of radiation machines or X-ray tubes. See also BPPM 20.80.

See BPPM 40.16 for information concerning transfers of sponsor-acquired equipment to other institutions.

Inventory Control Report

The department must complete an Inventory Control Report for the surplus or transfer of each radiation machine. See BPPM 20.50.

Send the original form to the recipient department and a copy to Property Inventory.

Surplus

Disconnect the X-ray tubes on all radiation machines which are to be offered for surplus as scrap or off-campus for X-ray uses.

Scrap

Authorized users of machines which are sold for scrap must arrange to have the X-ray tube disconnected and turned over to the RSO.

For state billing purposes, the RSO is required to adjust the state's tube count when the tubes are placed in an inactive status.

Reuse

Notification of Change in Responsibility

The RSO or the authorized user must complete Section 1 of the Notification of Change in Responsibility for a Radiation Machine form for each machine to be sent to Surplus Stores for sale and possible reuse.

Submit the original notification and the Inventory Control Report with the machine sent to Surplus Stores. See BPPM 20.50.

Submit a copy of the Notification of Change in Responsibility to the Radiation Safety Office (RSO).

Print the PDF master form on 9.22.16 or complete onscreen and print to make copies of the Notification of Change as needed.

Reactivation Notice

The RSO posts a Radiation Machine Reactivation Notice on all radiation machines destined for surplus or sale. The reactivation notice states that the RSO must be informed if the radiation machine is to be brought back into service.

Print the PDF master form on 9.22.17 or complete onscreen and print to make copies of the reactivation notice as needed.

Off-Campus Use

Disconnect the X-ray tube on those machines to be sent to Surplus Stores and designated for sale and possible reuse to entities outside WSU.

The tube may remain with the machine in the event of possible reuse. It is the responsibility of the purchaser to reconnect the tube.

If the equipment is to be used in the state of Washington, the purchaser is also responsible for notifying the Department of Health, Radiation Protection Division by telephone at 1-800-299-9729. (WAC 246-224-0020).

Surplus Stores completes Section 2 of the Notification of Change in Responsibility for a Radiation Machine and submits the form to the RSO.

Transfer Within WSU

Departments must directly coordinate with the RSO to transfer radiation machines within WSU.

The authorized machine user transferring the radiation machine must notify the RSO prior to the transfer.

The receiving user must complete and submit an Application to Use Radiation Machines and attached Radiation Machine Registration to obtain authorization to use the transferred radiation machine. See the PDF forms 9.20.13-14 and 9.20.15.

Inactive Radiation Machines

Inactive radiation machines, that were formally active under an authorized radiation machine user, are assigned to that machine user if the machine user continues to maintain other active radiation machines (including electron microscopes).

Other inactive radiation machines that are not the responsibility of an active authorized machine user must be assigned to a designated radiation machine contact person or authorized machine user. The responsible department must make this designation.

If the department is unable to assign an authorized machine user or machine contact the responsibility for the inactive radiation machine, then the machine must be transferred to another authorized recipient (on or off-campus) or surplused.

Coordinate all transfers and surplus efforts through the RSO.

STATE REGULATIONS

Applicable state regulations regarding these radiation machines include:

Copies of the state regulations are available for review at the Radiation Safety Office (RSO) or may be viewed at the Washington Administrative Code web site at:

http://apps.leg.wa.gov/wac/

Select Title 246: Health, Department of

WSU Certification

The Department of Health, Division of Radiation Protection, of the State of Washington issued Certification of Registration of Radiation Machine Facility #03783 to WSU.

Definitions

Washington State regulations are the defining authority. Radiation machines are classified in WAC Title 246 according to the following definitions:

Radiation Machine

"Radiation machine" means any device capable of producing ionizing radiation except those devices with radioactive materials as the only source of radiation. (WAC 246-220-010(96))

Cabinet Radiography (X-Ray)

"Cabinet radiography" means industrial radiography employing radiation machines conducted in an enclosure or cabinet so shielded that every location at the exterior of the enclosure or cabinet meets radiation dose limitations for individual members of the public, as specified in WAC 246-221-060. (WAC 246-227-020(1)(a))

Diagnostic X-Ray System

"Diagnostic X-ray system: means an X-ray system designed for irradiation of any part of the human or animal body for the purpose of recording or visualization for diagnostic purposes. (WAC 246-225-010(26))

Other Definitions

For definitions of other terms used in this section refer to WAC 246-220-010, WAC 246-225-010, WAC 246-227-020, and WAC 246-228-010.

See the PDF master forms:
9.22.16: Notification of Change in Responsibility for a Radiation Machine
9.22.17: Radiation Machine Reactivation Notice
Print or complete onscreen and print as needed