If runway identification lights are also controlled by type K ARCAL, they may be turned off by keying the microphone three times.
This is so that the lighting does not turn off at a critical moment, such as when crossing the runway threshold.
When in operation, the receiver awaits a squelch break on the tuned VHF frequency and begins counting "clicks" in a five-second period to determine pilot intent.
The pilot commanded output is held by the controller for a predetermined time interval (Federal Aviation Administration standard is 15 minutes) that is generally adjustable.
In the United States, pilot-controlled lighting is governed by Federal Communications Commission Rule 87.187y.