10.10.4 Isolation Of RF Sources
Where reasonably practicable, exposure should be eliminated for the task by de-energizing, isolating, and verifying the relevant RF sources before access to a location where the occupational limits could otherwise be exceeded.
- The isolation arrangement may require:
- placing every relevant transmitter in the specified non-transmitting state;
- disabling remote, automatic, scheduled, or fault-recovery restart functions;
- disconnecting or inhibiting RF power or antenna feeds at an identified isolation point;
- securing local and remote controls against unauthorized operation;
- applying the site's lockout and tagout system where it is applicable; and
- verifying the source state and preventing inadvertent re-energization.
The isolation must cover every source that can affect the work. Switching off a control, issuing an outage instruction, or observing that a transmitter is idle is not by itself proof that the RF hazard has been eliminated.
10.10.5 Lock-Out And Tag-Out
Where the site's energy-control system uses lockout and tagout, it should prevent a source from being restored until the people protected by the isolation have formally released it.
The arrangement should define:
- the identified isolation points and the safe source state;
- who may apply, transfer, verify, and remove locks or other controls;
- the tags or records that identify the work, protected people, and responsible person;
- how shift changes, multiple work groups, and lost or unavailable keys are managed; and
- how remote operators and other source owners are prevented from restoring service.
Locks and tags do not themselves prove the absence of RF. Restoration should occur only after the defined handback process confirms that people, tools, temporary equipment, and work restrictions have been accounted for.