Blue light district: Dublin authorities replace thousands of faulty streetlights after they turn blue

Three local councils contact manufacturers after some public lighting shifted from warm white to blue

Even Dublin’s streetlights have the winter blues this year. Three local authorities have had to replace thousands of lanterns after faults caused the colour of the light they produce to shift from warm white to a more azure hue.

Dún Laoghaire-Rathdown County Council, South Dublin County Council and Fingal County Council have replaced a combined total of about 2,000 “blue-shifted” lanterns, but Dublin City Council said it did not encounter any instances of LED lights giving off a blue tone in its area.

Dún Laoghaire-Rathdown said it replaced 1,500 faulty lanterns since its public lighting section became aware of the issue last November.

“We tracked the issue down to one batch of LEDs used by one manufacturer for one lantern type supplied in one manufacture year. We made the manufacturer aware of the situation and a repair system was created that has allowed us to remove, replace, repair and track this issue as quickly as possible,” a spokeswoman said.


“Up to September 2022, we have identified 3,060 potential lights and identified 1,915 faulty lanterns and replaced 1,500. Monitoring and repair works will continue until this issue has been fully resolved.”

The council did not provide the name of the company who supplied the lanterns.

South Dublin County Council said it received reports of 180 blue lanterns, some 145 of which have been replaced. “These lanterns are under warranty and we have now agreed a process with the manufacturer for their removal and replacement,” the council said. “Whilst they are not as comfortable to our eyes, they are no brighter than the warm white colour and as such are not causing any environmental damage.”

The council said it purchased the lanterns in early 2019 from a company called Holophane under a formal public procurement process at a cost of €90,000 and has installed about 500 of them. It said the issue with the lights turning blue was brought to its attention in March.

In a statement, Holophane said “the referenced ‘blue light’ effect occurred in a small percentage of Holophane Europe fixtures with components that have not been sold for several years. It is due to a spectral shift caused by phosphor displacement seen years after initial installation. The light output is in no way harmful or unsafe.

“As always, we stand behind the quality of our products, and we have been proactively working with customers who have experienced the issue to address any concerns.”

Fingal County Council said it had identified 178 faulty lanterns, which it is in the process of replacing. It said “a nightly patroller” who covers the whole of the county during a five-week period monitoring lighting performance had noted a marked change in the lighting colour of some of our lanterns, from warm white to blue. The council declined to reveal the name of the manufacturer of its lights.

“The manufacturer was contacted and a plan was put in place to replace these faulty units, with this work taking place at present,” a spokeswoman said.

Dan Griffin

Dan Griffin

Dan Griffin is an Irish Times journalist