It's a stormy Friday night in Norwich, but local teenagers aren't deterred by a bit of wind and rain. By 10pm, the Riverside quarter is packed with club-goers, with girls tottering around in a uniform of micro-skirts and stilettos, lads swaggering after them. Many of the revellers have already had one drink too many, and it seems unlikely they will remain upright much longer.
"We'll be seeing them in trouble later," says John Pettifer, a St John Ambulance first-aider who volunteers for Norwich's Home Safe and Sound initiative. The project was set up in 2001 after two Norwich teenagers drowned in alcohol-related accidents.
The focus of the scheme is the SOS Bus, which overlooks the main clubbing district between 9pm and 3am every Friday and Saturday night. It is staffed by a nine-strong team of volunteers, including first aid workers, a youth worker, a drugs adviser and security officers.
On busy nights, the makeshift medical centre is as hectic as a hospital A&E department. Pettifer says: "Sometimes we've had one person at either end of the bed and half a dozen waiting for treatment outside."
The bus doubles as a refuge for people who are alone or vulnerable. Paul MacIntyre, a previous manager of the project, says: "If bouncers see a girl leaving a club on her own and she's getting hassle, they'll radio us, and someone can run down in the minibus and make sure she's OK."
The Norwich project has been nominated for the Queen's Award for Voluntary Service, and St John Ambulance is looking at extending it to other cities.
Representatives from Cambridge visited the SOS Bus last weekend, recognising that such a scheme might help to prevent tragedies such as the murder of Sally Geeson, the Cambridge student who accepted a lift home with a stranger after her losing her friends on New Year's Eve.