You can’t beat using traditional pyrotechnic flares for being found during a search and rescue operation at sea. They are unmistakably visible as distress flares during a visual search, and can’t be confused with a strong navigation light.
They are also unbeatable when the search is using infrared cameras which pick up the heat of the flare. Keeping pyrotechnics on board is vital for sending a clear and unmistakable distress message if in need of rescue at sea.
UK Maritime & Coastguard agency provides the latest advice to mariners on products sold as distress signalling equipment to be used in an emergency. It highlights the risks of using non-SOLAS or non-pyrotechnic distress flares such as Electronic Visual Distress Signals (EVDS).
Read this information in full here.