What is the civil-AGL interface?
Where the civil works and the lighting works meet — ducts, pits, bases, pavement and drainage — and how responsibility, sequence and checks are agreed so nothing is covered before it is right.
The civil-AGL interface is the boundary where the civil works and the lighting works meet. The sequence is to agree responsibilities and details first, set out from shared survey control, build the civil parts, stop at a joint hold point before paving or concrete covers anything, then fit the lighting and close out with as-built records.
Problems here are usually about coordination rather than skill: two teams on two programmes, with an item that each assumed the other would finish. Who owns base cans, ducts and sealant depends on the contract, so it is written down, not assumed. Excavation, saw-cutting and paving work is done under the airport’s permit-to-work with existing cables located and protected, and any AGL circuit is isolated before work near its cables.
- Agree. Settle the scope split, drawings, tolerances and who owns each item before work starts.
- Set out. Use shared survey control and mark each position and level.
- Build civil. Construct ducts, pits, bases and foundations to the agreed detail.
- Hold point. Check jointly and sign off before concrete or asphalt covers the work.
- Fit AGL. Install cables, fixtures and sealing, then test the circuit.
- Close out. Complete as-built records and the defects list, then hand over.
Frequently Asked Questions
Q1What is the civil-AGL interface?
It is the boundary where the civil works and the lighting works meet: ducts and pits, base cans and foundations, slots and saw cuts in the pavement, sealant, drainage and cable routes. It also covers who is responsible for each item, in what order the work happens and how it is checked and handed over.
Q2Why is the interface a common source of problems?
Two teams, often two contractors, work from different drawings and on different programmes. If positions, levels or sequence are not agreed, bases end up misplaced, ducts are covered before they are checked, or sealant and drainage are left unfinished because each side assumed the other would do it.
Q3What is a hold point?
A hold point is a stage at which work stops until a named person has checked and signed it off. At the civil-AGL interface a typical hold point comes before concrete or asphalt covers ducts, base cans or foundations, because correcting them afterwards is slow and expensive.
Q4Who is responsible for base cans, ducts and sealant?
It depends on the contract. Some projects give base cans and foundations to the civil contractor and others to the lighting contractor. The interface agreement and drawings define it, so it should be written down and not assumed.
Q5What should be agreed in writing?
The split of scope, the handover points, the tolerances, the survey control and set-out, the order and timing of work, access and permits, who tests and signs off each stage, who repairs sealant after overlay, and the format of as-built records.
Q6What limits and standards apply?
Tolerances, hold points and responsibilities come from the project specification, the design, the regulator, the applicable standard and the manufacturers' instructions. Always use the requirements for your site rather than a generic list.
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