Draft Reporting Lighting Column Serviceability

1. Lighting Column Serviceability

The term Lighting Column Serviceability is used here to describe the Lighting Column’s fitness for purpose and remaining safe operating life.

Lighting Column Serviceability could be be reduced by many factors including

• Corrosion
• Cracks in both the base material and in welds caused by cyclic wind loads, overloading or physical damage.
• Deformation and structural caused by external impact.
• Fatigue cracks, corrosion and tightness of fasteners and anchor bolts.
• Lean caused foundation failure or ground settlement.
• The condition of non-structural parts that could affect public safety or accelerate deterioration. e.g. Access panels to electrical components.
• The condition of any signs, hanging baskets, flags, bunting, street decorations or any other objects that have been attached to the lighting column.
• Any factor that might cause or accelerate deterioration. e.g. The build up of litter, soil, rotting vegetable matter, vegetation and other foreign materials.
• Any factor that might prevent or obscure the prompt detection of the above faults or any other predictor of deterioration. e.g. Tarmac, concrete, soil or loose fill intentionally placed over flange joints and anchor bolts.

Caspian NDT provides reports for every lighting column that has been inspected.

The inspection reports include

• Unique asset number and location reference.
• Visual estimates and quantitative measurements of all factors listed above.
• An assessment of the current level of corrosion in accordance with ILP GN22. (See below).
• An analysis of the factors above to the current status and remaining safe operating life.
• A recommendation for implementation of safety precautions, repair or removal in the case of defects that create an immediate risk to public safety.

2. Reporting of Lighting Column Corrosion

Lighting column column corrosion is reported as an estimated average percentage loss thickness.

The estimate percentage loss of thickness is referred to as ‘Loss of Section Units’ (LSU’s).
The LSU data is used to classify the column “GN22 Category”.

A recommendation for the future safe use of the lighting column is made based on the Institution of Lighting Professionals ILP GN22 Guidance Note 22 Asset-Management Toolkit: Minor Structures (ATOMS) 2019 “GN22 Category”.

See Table below.

Note 1 Caspian NDT will always assess material loss in conjunction with other factors that might further increase risk of failure. For example,

a) The location of corrosion and its proximity to stress concentrations or features that will magnify any risk failure . For example, corrosion could increase an existing stress concentration by increasing the sharpness of a “notch”.

b) Corrosion could also be more critical in areas of dents, impact or coating damage.

c) Any changes that might have taken place since the lighting column was installed. Some changes might have already reduced the original design safety margins. For example, the fitting of heavier low energy luminaires, signs, street decorations etc.