What is decommissioning?
Taking an asset out of service for good — authorised, isolated, made safe, removed or abandoned, and taken off the records.
Decommissioning is the controlled, permanent withdrawal of an asset from service. It is authorised, the circuit is isolated, locked and tagged, and the asset is disconnected with cable ends made safe and the circuit kept sound for the lights that remain.
The asset is removed or deliberately left in place, the drawings, asset register and control and monitoring are updated, and the remaining system is confirmed before the items are handed on to disposal. Poor decommissioning leaves live leftovers, broken circuits and wrong records.
- Authorise. Confirm the decision, obtain approvals and notice, and inform operations.
- Isolate. Switch off the constant current regulator (CCR) and the circuit, lock out and tag it under the permit, prove it dead and earth it as the safe-working procedure requires.
- Disconnect. Disconnect the asset and terminate or link the cable ends safely, so the series loop stays closed and sound for the lights that remain.
- Remove. Remove the asset or abandon it in place where permitted, clear the base can and restore the surface.
- Update. Correct the drawings and layouts, the asset register, and the control and monitoring systems.
- Confirm. Re-test the remaining circuit, check the regulator loading and output current, confirm the lighting is still compliant, and hand the items to disposal.
The controlled withdrawal of an asset from service: made safe, disconnected, removed or abandoned, and recorded.
What happens to the removed items afterwards, such as reuse, recycling or scrapping (a later lifecycle entry).
Frequently Asked Questions
Q1What is decommissioning in airfield ground lighting?
The controlled, permanent withdrawal of an AGL asset from service. The asset is isolated, disconnected and made safe, removed or deliberately left in place, and taken out of the drawings, records and control and monitoring systems, so that nothing live, unsafe or misleading is left behind.
Q2How is decommissioning different from replacement and disposal?
Replacement fits a new asset to do the same job. Decommissioning is the withdrawal of the old asset from service, whether or not a new one follows. Disposal is what happens to the removed items afterwards, such as reuse, resale, recycling or scrapping, and is a later stage of the lifecycle.
Q3Why is the circuit isolated, and why must it stay sound?
AGL circuits are usually series circuits fed from a constant current regulator, so work is done only on an isolated, locked and tagged circuit under a permit to work. Removing an item must not leave the circuit open or the remaining lights affected, since an energised series circuit must never be left open: cable ends are terminated safely, the loop is kept continuous, and the circuit is tested before it is re-energised.
Q4Is equipment always removed?
Not always. Items such as buried cable or base cans may be left in place where the aerodrome's procedures allow it, provided they are disconnected, made safe, capped or sealed, recorded accurately, and not a hazard to aircraft, vehicles or future works. Anything left in place is shown on the drawings as abandoned.
Q5Why update records, drawings and monitoring?
Out-of-date records create ghost assets, false alarms and drawings that no longer match the airfield. Abandoned cable that is not marked as such could later be treated as live or as available. Accurate records protect future maintenance and construction crews and keep asset planning correct.
Q6What is checked at the end of decommissioning?
That the remaining circuit tests sound, that the regulator loading and output current are still correct, that the lighting still works and still meets its requirements, that the area is left clean, safe and free of debris, that the people concerned have been informed, and that the removed items are correctly identified and handed on for disposal. Acceptance and notification follow the aerodrome's procedures and the regulator's requirements.
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