AGL Marker Posts for Cable Route Identification

What It Is

Marker posts identify underground cable routes, infrastructure and selected airfield equipment locations. They are configured for the cable route, identification requirements, site conditions and project specifications.

Key Features

• Visible identification of underground AGL infrastructure
• Supports cable-route identification and maintenance
• Suitable for primary and secondary cable routes
• Positioned at selected junction and crossing locations
• Configurable marking and identification information
• Material selected for outdoor airfield conditions
• Suitable for new and existing infrastructure
• Coordinated with cable records and site drawings

Role

Marker posts help maintenance personnel locate buried infrastructure during inspection, testing and repair. Identification can include relevant cable, circuit or infrastructure references per the project documentation.

Principle

Keep the marking arrangement consistent with the project's cable identification system.

Role

Primary AGL series-circuit cables are commonly buried between CCR equipment, field transformers and associated lighting circuits. Markers at selected points indicate buried infrastructure and support maintenance.

Coordinate With

• Cable route drawings, circuit identification
• Crossing locations, junction points
• Transformer locations, junction pits and handholes
• Existing airport infrastructure

Role

Marker posts can identify selected secondary cable routes where route identification is required.

Principle

The identification system should correspond with the project's equipment and cable records.

Typical Locations

• Junction pits, handholes
• Cable joints, cable crossings
• Branch routes, equipment interfaces

Benefit

Clear identification can reduce the time needed to locate underground infrastructure during maintenance.

Possible Information

• Cable or circuit reference, equipment reference
• Route and junction identification
• Warning or service identification
• Project-specific coding

Principle

The final legend and marking format should follow the approved project documentation.

Material Selection Should Consider

• Weather resistance, UV exposure
• Mechanical durability, visibility
• Corrosion resistance where applicable
• Long-term legibility of markings

Exposure

Posts may face sunlight, rain, temperature variation, soil contact and routine airfield maintenance activities.

Role

Marker posts give a reference for the approximate location of the crossing and support future maintenance or civil works.

Records

Record the position accurately in the project's as-built documentation.

Coordinate With

• Cable ducts, cable protection
• Junction pits, handholes
• Primary cable, secondary cable routes
• Cable identification tags

Result

This creates a consistent identification system across the underground AGL infrastructure.

Check During Inspection

• Damage or displacement, loose foundations
• Faded or illegible markings
• Corrosion or material deterioration
• Obstruction by vegetation or soil
• Changes to surrounding infrastructure

Action

Replace damaged or missing posts according to the approved identification scheme. Position posts so they do not obstruct aircraft or vehicle operations.

Use

Markers can be added or replaced during rehabilitation projects where existing underground cable identification is inadequate.

Existing Installations

Coordinate with available cable drawings, survey information and verified field locations before installing new markers.

Treat Every Marked Cable as Live

Primary AGL cables carry series-circuit current at up to 5,000 V insulation class. A post shows the route only. Before any excavation, follow the airport permit-to-work and cable-locate procedure, and never assume a marked cable is de-energised. Never cut or open an energised series circuit.

Siting on the Airfield

Equipment on the operational area must be frangible and mounted as low as its function allows (Annex 14, Vol. I, Chapter 9). Confirm with the airport before placing any post inside a runway or taxiway strip. Posts must not obstruct aircraft, vehicles, signs or lights, and must not be a substitute for accurate as-built records.

References

• ICAO Annex 14, Vol. I, Chapter 9: siting and frangibility of equipment on operational areas
• ICAO Doc 9157 Part 5: electrical systems, and Part 6: frangibility
• FAA AC 150/5340-30J: design and installation details for airport visual aids
• FAA AC 150/5370-10 (Item L-108): installation of underground airport power cable
• DGCA India requirements and the airport cable-records system

Project Requirements

Height, material, colour, marking method, foundation and legend follow the site cable-marking system. Record every post in the as-built drawings.