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Requirements:
General (5.1)

All RF sources and all significant reconfigurations of existing sources are subject to review by the Non-ionizing Radiation Safety Committee (NIRSC). A review is initiated by contacting the NIRSC to determine if a hazard analysis is required. If the hazard analysis shows that potential RF radiation may exceed action levels, the equipment owner must develop a facility-specific radio frequency safety program (RFSP).

The RFSP is reviewed by the NIRSC and approved once all safety measures and requirements are documented, reviewed by experts, and communicated. Implementing an effective RFSP ensures that controlled RF environments are identified and that the maximum permissible exposure (MPE) limits are not exceeded either in normal operation, or in the event of a credible accident or failure. RFSPs for existing equipment are reviewed periodically.

Hazard Determination (5.1.1)

Review Requirement (5.1.1.1)

NIRSC review is required if the equipment belongs to one of the following types:

• Permanently installed RF gear capable of radiating over 1 Watt (W) at frequencies between 3 kilohertz (kHz) and 300 gigahertz (GHz). Such installations include klystrons and RF waveguide systems.
• Satellite and permanently installed communications transmitters (not receivers)
• Industrial induction heaters and large-scale ultrasonic cleaners may need to be reviewed. Contact the NIRSC for details.

NIRSC review can also be required by one or more of the following:

• Discussion of a project at a Safety Overview Committee (SOC) meeting, where the project may be referred to the NIRSC for review
• Recognition of a hazard by line management
• Results of a non-ionizing radiation survey that was conducted by a qualified person, such as an ES&H industrial hygienist or a NIRSC member

Preliminary Hazard Analysis (5.1.1.2)

A preliminary hazard analysis is key in determining if a facility-specific RFSP is required. If the hazard analysis demonstrates that the equipment poses no hazard, the NIRSC may approve the equipment for the described use at this stage. For equipment that may pose a hazard, the NIRSC will set RFSP requirements.

Radio Frequency Safety Program Development (5.1.2)

The equipment owner of RF-generating installations must ensure that all equipment is reviewed by the NIRSC for its potential to exceed the action levels indicated in IEEE Std C95.1-2005.

An RFSP includes detailed consideration of items detailed in sections 5.1.2.1 through 5.1.2.5.

Equipment Description (5.1.2.1)

A complete description of RF-generating equipment includes

• Equipment location(s)
• Intended use
• Output characteristics, including
• Frequency
• Peak power
• Average power
• Modulation characteristics
• Duty factor

Hazard Analysis (5.1.2.2)

The hazard analysis must evaluate the potential hazards associated with the RF source(s), both in normal operation and in the event of a credible accident or failure. Supporting materials must be submitted to the NIRSC along with the analysis. (For RF MPEs and action levels, see Non-ionizing Radiation: Selected Radio Frequency Exposure Limits [pdf] for thresholds that most commonly apply at SLAC, or see the IEEE Std C95.1-2005 for all thresholds.)

Hazard Controls (5.1.2.3)

The hazards control section must include a description of engineering, work practice, and administrative controls.

Engineering Controls

Insofar as possible, engineering controls such as confinement of the RF fields, shielding, and interlocks should be the preferred means of hazard control. These are the most effective in attaining the goal of eliminating hazardous levels of uncontained RF energy in occupied areas.

For example, high-power systems that generate hazardous levels of RF energy should ideally be equipped with redundant interlocks that shut the equipment off if the integrity of any of the elements or connections is damaged. All interlocks should be managed so that they are recertified periodically.

Administrative Controls for Controlled RF Environments

Administrative controls rely heavily on hazard communication and minimizing access. The following should be incorporated into the RFSP as appropriate.

• Equipment Lockout Procedure (ELP). An ELP specific to the RF source(s) must be developed so that the equipment can be serviced safely. For guidelines, see Non-ionizing Radiation: Radio Frequency Equipment Lockout Procedure Guidelines [pdf]. Any additional work practice procedures that will ensure worker safety should be developed as necessary or as required by the NIRSC.
• Warning signs. Signs must be placed to warn personnel of potential RF hazards, both in the controlled RF area and on equipment elements. Contact the NIRSC for assistance in determining appropriate signage.
• Access limitation. Program managers and facility managers must ensure that, where required by the RFSP, the operational supervisor controls access to controlled RF environments.

Hazard Awareness Training and Documentation of Training Requirements (5.1.2.4)

The RFSP must include all requirements for RF awareness training, such as a description of on-the-job training specific to the equipment or installation. For additional guidance, see IEEE Std C95.7-2005, Annex A.

Procedures and Monitoring Requirements (5.1.2.5)

The RFSP must address

• Configuring the system and bringing it online
• Ensuring that the interlocks are operational
• Monitoring the system to detect RF radiation. The RF monitoring procedure should specify the survey method and how and where results must be documented.
• Installing and using safeguards to protect against credible accidents or failures

Radio Frequency Safety Program Approval and Periodic Review (5.1.2.6)

Once an RFSP has been reviewed and approved by the NIRSC, the area, equipment, or installation will become a controlled RF environment subject to the provisions of the approved RFSP.

All RFSPs are subject to periodic NIRSC review; the frequency of the review will be determined by the NIRSC.

Operation (5.1.3)

Before an RF source is energized the following conditions must be met.

• The approved RFSP must be on file with the equipment owner and the NIRSC.
• All engineering, work practice, and administrative controls, as described in the RFSP, must be in place.

All work must be performed in compliance with the approved RFSP. If there is an actual or suspected RF overexposure, line management must ensure that the accident is handled in accordance with Chapter 28, "Incident Investigation".

Servicing, Maintenance, and Repair (5.1.4)

Any system under an RFSP must be locked out and tagged out according to requirements specific to the procedure developed for the RFSP. For general guidelines, see Non-ionizing Radiation: Radio Frequency Equipment Lockout Procedure Guidelines [pdf].

If a repair involves the engineering controls required by the RFSP, the system must be recertified according to specifications in the RFSP.

Recordkeeping (5.1.5)

Equipment Owners (5.1.5.1)

Equipment owners must keep on file

• A current inventory of potential RF hazards
• The current RFSP for their RF-generating equipment, and associated documents required by the RFSP
• Requests for operational variance and subsequent approvals

Facility Managers (5.1.5.2)

Facility managers must keep on file

• An area hazard analysis (AHA) that includes potential RF hazards

NIRSC (5.1.5.3)

The NIRSC must keep on file

• A copy of approved RFSPs
• A compilation of available inventories of potential RF hazards at SLAC

Personnel (5.1.6)

Qualifications (5.1.6.1)

Line management must ensure that persons working in controlled RF environments have completed required on-the-job training and that only qualified persons conduct surveys to measure non-ionizing radiation.

Medical (5.1.6.2)

SLAC workers, users, subcontractors, and visitors who wear a medical electronic implant such as a cardiac pacemaker, or who have ferromagnetic implants are strongly encouraged to obtain medical clearance from their treating physician (who has knowledge of the implanted device) before working at or visiting SLAC. For details from the IEEE standard, see Non-ionizing Radiation: Medical Information Guideline [pdf].

continue to Requirements, Roles & Responsibilities (5.1.7)