A family trip to the beach ended in a painful ordeal for a 27-year-old man after he suffered third-degree burns after unknowingly stepping on sand that had been heated by a disposable barbecue.The incident has prompted burn specialists to warn that the hidden danger can remain long after the flames have been extinguished. What Happened? The incident occurred at Cefn Sidan Beach in Carmarthenshire, Wales, where Sam Knight had arrived to spend the day with his family. According to local reports, Knight moved the disposable barbecue with tongs and poured water over it to extinguish the residual flame before leaving. Believing the area was safe, he later walked barefoot over the same spot, only to step onto extremely hot sand beneath the surface."I instantly knew something wasn't right. I couldn't stand on my feet," Knight recalled. Family members had to carry him off the beach before he was taken to hospital for treatment. He was later referred to a specialist burns unit and was unable to work for two weeks while recovering. Knight said he shared his experience to raise awareness about a hazard many beachgoers may not think about."I didn't realise the sand could stay that hot after the barbecue had been put out. I just don't want anyone else to go through what I did."Also read: Europe Swelters Under Heatwave And Wildfires; 360,000+ Evacuated: What Are The Health Risks?Why Hot Sand Can Be More Dangerous Than The Barbecue?Burn specialists say the barbecue itself is not always the greatest risk. But the sand beneath it can absorb and retain extreme heat, remaining hot enough to cause third-degree burns even after the barbecue has been removed.David Fligelstone, Consultant Plastic Surgeon at Swansea Bay University Health Board's Welsh Centre for Burns and Plastic Surgery, warned that people often underestimate how long the heat can remain trapped."The sand underneath a disposable barbecue can stay dangerously hot even after the barbecue has been removed. People assume it's safe because they can't see the heat, but the injury can be severe," he said. Also read: UK, France Brace for Another Heatwave: How Hot Weather Can Affect MedicinesHow To Stay Safe? Third-degree burns are among the most severe burn injuries. They destroy all layers of the skin and may damage deeper tissues, nerves and blood vessels. These burns typically require specialist medical care and can take weeks or even months to heal. Burns affecting the feet are particularly concerning because they can make walking difficult and increase the risk of infection.Experts recommend a few simple precautions when using disposable barbecues:Never place a disposable barbecue directly on sand.Use a suitable stand or designated barbecue area whenever possible.Allow the barbecue to cool completely before disposing of it.Do not bury hot coals or cover them with sand, as the heat can remain trapped beneath the surface.Keep children and pets away from areas where a barbecue has recently been used.If you are not sure whether sand is safe, avoid walking barefoot around area.