Introduction to RF Radiation Safety / 10 / 10.8 / 10.8.2

10.8.2 Occupational Access Within A Controlled Area

Within a Controlled Area, some locations may exceed the public limits while remaining within the occupational limits. Other locations may exceed the occupational limits and must be separately delineated and made inaccessible until appropriate controls reduce exposure.

Access above the public limits is limited to people covered by an appropriate occupational exposure category and provided with the information, training, instruction, supervision, and controls required for the proposed activity.

Contractors should be classified according to their work and potential exposure. A Supervised Visitor may transit a Controlled Area only under direct supervision and below the occupational limits; visitor status is not a substitute for the training and classification required to perform RF work.

10.8.3 Site-Defined Exclusion Zones

An exclusion zone is a site-defined area in which entry is prohibited while specified RF equipment is operating. It commonly encompasses a location where occupational limits may be exceeded, together with any margin needed to make the boundary clear and reliably controlled.

Exclusion zones may be permanent for a defined source state or established temporarily for a task.

Permanent zones may be used around high-power broadcasting antennas, radar systems, or industrial RF plant whose operating geometry is stable.

Temporary zones may be needed during testing, commissioning, maintenance, fault conditions, or unusual operating modes. Their dimensions and access conditions should be stated for the relevant transmitter power, frequency, antenna orientation, beam position, and duty cycle.

Where reasonably practicable, entry should be prevented by barriers, locked access, interlocks, isolation, or other higher-order controls rather than by signs alone.