The fourth emergency service: how watersports boom means lifeboatmen are busier than ever

The most challenging lifeboat callout for Mike Hallard came when a boat that had developed a gas leak exploded. "Parts of it landed on nearby roofs," he recalls. "One guy had his legs blown off and was bleeding to death, trapped below in the cabin as it sank. "Me and the coxswain crawled through the splintered wreck with the water rising all the time, trying to get him out. It was great to help save his life."

Such dramas are all in a day's work for those manning Britain's busiest lifeboat station. As they braved the unforgiving February winds over the weekend, the volunteers at Poole RNLI station could at least console themselves with the not inconsiderable feat of saving 145 lives in 2005.

Mr Hallard, a 54-year-old fisherman, is one of 4,500 volunteers across Britain who drop everything, at any time of the day or night, any day of the year, to save those in danger at sea. They are crew members of the Royal National Lifeboat Institution, a charity that is reliant on public donors.

The RNLI runs 233 lifeboat stations around the coasts of Britain and Ireland, providing a full-time search and rescue service within 100 nautical miles of land. It claims to account for 90 per cent of all those plucked from the water. Just one in 10 crew have a maritime background; the remainder include teachers, hairdressers, housewives and chefs.

Last year they rescued record numbers of people from British waters: 8,104, up from 7,507 in 2004. Almost half came during June, July and August - mostly bathers, watersports enthusiasts and yachters.

The lifeboatmen's "shouts" range from dealing with the mundane - an amateur boater who runs out of fuel - to the bizarre. Since 1997, three babies have been born on board the Oban lifeboat, which habitually transports women in the last stages of pregnancy from the Isle of Mull to the Scottish mainland.

It was hardly Baywatch weather last week in the Swash Channel, just outside Poole Harbour, as crewmen underwent one of their twice-weekly training exercises. The new £2m Tamar-class lifeboat, which is fitted with cutting-edge navigation and rescue technology, bucked and boomed amid the 7ft waves, tossing its human cargo from one side of the deck to the other.

But the lifeboatmen seemed comfortable with the conditions. "This isn't bad," said Robert Aggas, 39. "In 1996, in the middle of the night, we attended a yacht sinking 20 miles south of Anvil Point in hurricane winds of 112mph. The helicopter couldn't winch so we had to pull five people off. At one point I saw the yacht's mast go under the water and come back up.

"That's when the adrenalin and training kick in and you're on autopilot." The wreck later turned up on the coast of the Isle of Wight.

The last lifeboat to sink was the Solomon Browne, from RNLI Penlee in Cornwall, on 19 December 1981. All eight crew lost their lives attempting to aid the Union Star freighter in treacherous seas off the south coast of Cornwall. Crewmen now seem dismissive of the dangers, although they acknowledge the worry they put their families through. "I think it is tough for my wife when we're out, when the windows at home are rattling and the trees are bending in the storm," admits Mr Hallard, who joined the RNLI in 1977. "She has no idea of knowing whether I'm OK until I come back through the door in the early hours."

So why does he do it? "Because I've worked on water all my life," he said. "And like to think someone would do the same for me."

The reality of their job is, unsurprisingly, far from its portrayal in the 1990s television series Baywatch, which starred David Hasselhoff and Pamela Anderson. "Does this look glamorous?" asks Jake Scott, 40, helmsman of a small inflatable boat at Weston-super-Mare, and a manager at a flight simulator company by day.

Michael Vlasto, operations director at the RNLI's £25m headquarters and training complex in Poole, agrees. "We're low on the silicon implants. Our people are both part-time volunteers and absolute professionals, not the sort to prance around demonstrating their physique. What they share is a camaraderie and a deep care for all who use the sea."

Training the crews, who by the end of this year will have saved close to 150,000 lives across Britain and Ireland since the RNLI began, costs £1,000 per person per year.

Sir William Hillary, who founded the institution in 1824, could have had little idea how the primitive craft of his era would evolve into hi-tech superboats, but he would have recognised the bottom line for the men and women who crew the orange and blue boats of the RNLI: that there is no feeling quite like grasping a hand and pulling another human being from death's icy clutch.