Harland and Wolff workers will sound the shipyard horn on tonight to show their appreciation for NHS and frontline staff.
The rare occurrence will take place from 8pm on April 8th for one minute and will be live streamed by participants.
It comes as part of the third 'Clap for Carers' event that has took place in recent weeks to show solidarity with healthcare workers in the face of the Covid-19 pandemic.
Last week, docked ships sounded their horns in Belfast Harbour to celebrate frontline staff working there, including hauliers, stevedors, and harbour police.
Stormont is also expected to once again be illuminated with blue lighting in honour of healthcare workers.
A spokesperson for Unite the Union, which represents the workers at the shipyard, said: "Harland and Wolff workers will sound the shipyard horn for a minute at 8pm tonight to show their appreciation and that of workers across Northern Ireland for frontline National Health Service staff and those working to sustain other frontline services in the face of the Covid-19 pandemic.
"The shipyard horn has not been sounded properly in twenty years and is the loudest siren in Belfast; it will be heard in all parts of the city."
