"White-knuckle" rides are getting faster, higher and more challenging each year in an attempt to satisfy the public's lust for fear and excitement, and Britain is now a leading rollercoaster nation.
In the past 18 months, several of the most demanding rides yet have opened.
Blackpool Pleasure Beach now boasts the tallest and fastest "coaster" in the world (The Big One). Chessington World of Adventure, Surrey, has just opened a new, somersaulting, stomach-churner called Rameses' Revenge. And lurking in a pit at Alton Towers in Staffordshire is Nemesis, the current favourite of the Rollercoaster Club of Great Britain. All are far more physically challenging than traditional fairground rides and carry warning notices for people with nervous dispositions or medical infirmities.
But as theme parks and fairgrounds reach for the sky, and riders reach for their wallets, safety bodies are concerned that standards will not keep pace.
The Royal Society for the Prevention of Accidents is worried that the 14-month gap between thorough examinations by the Health and Safety Executive (HSE) might be too long. "We have a habit of not doing anything in this country unless we have a horrendous accident, and the time to increase safety measures would be now," said its spokeswoman, Cathy Ward.
The British Standards Institution is also pushing "fairly vigorously" for a safety policy to cover all rides, but is running into difficulties because of the bespoke nature of the industry: rides are increasingly built specifically for certain parks.
The British Safety Council's director general, James Tye,agrees that action is needed to prevent a disaster. "Despite an increase in safety standards in British theme parks, many white-knuckle rides are, by their very nature, dangerous," he said. "We think that safety is still lax generally and enforcement of safety regulations is almost non-existent."
However, the HSE, which is responsible for enforcing the Health and Safety at Work Act, said that the wilder the rides were, the stricter the safety procedures, and Leslie Beaumont, a senior principal inspector, said that hi-tech often meant high safety.
"It's true that the faster something goes, the more harm it is likely to cause if something goes wrong, but we are getting more reports of accidents on the low-tech conventional rides in a travelling funfair," he said.
"On the whole, these theme park ones are well-designed and checked, but that doesn't mean the owners can relax.
"We also recommend daily checks."
HSE figures show that the number of reported accidents has remained stable during the past few years, averaging 100 per year. Nine people were killed on rides in the seven years to 1994.
For the public, the new generation of terror rides are still not taxing enough. Clutching his girlfriend tightly in delight after stepping from The Big One, Barrie Wight, a gas fitter from Chesterfield, was ready for more. "It's great, but they should have it so you do the first big drop at the end as well, to finish it off," he said.
The "big drop" is a 235ft plunge at a 60-degree angle which hurls riders down at 85mph and submits them to forces three-and-a-half times that of gravity.
These G-forces are still less than Nemesis at Alton Towers, but that doesn't seem to put off the thousands who queue patiently for up to two hours to board.
Andy Bull, marketing manager for Alton Towers, said that safety was of the highest importance. "We take it very seriously. If anything happened to anyone on any of our rides, we would be finished," he said. "And we always have to bear in mind the human condition. You can't put people through what an astronaut would go through in training."
But that is just what rollercoaster enthusiasts such as Justin Garvanovic, co-founder of the Rollercoaster Club of Great Britain, are after. He said: "If you step back 30 years, people would have said they can't get any scarier. Well, they have - a lot scarier.
"And they will get as scary as the riders let them."
Designers had been aiming for a 200ft drop, Mr Garvanovic said. "That was the mythical figure. Well, now they've got that at Blackpool everyone is going for a 100mph coaster. For that they need roughly a 350ft drop and we've heard they're building one that big in the States at the moment.
"We've still got some way to go yet before people are too scared." THRILL GUIDE Rameses' Revenge, Chessington World of Adventure: Riders on a large bench are somersaulted violently, held static upside down and splashed with water. Has been likened to a Red Arrows aerobatics training session. Duration: Av 1min 30sec Price: Gate price (pounds 14.50 adults, pounds 11.50 children) includes unlimited rides Dangers: Anyone with heart, neck or back trouble, those pregnant or prone to blackouts should not ride. Originality: 8/10 Fear factor: 7/10 Fun factor: 7/10 Overheard: "Nothing like it. Where's the loo?"
Nemesis, Alton Towers: Riders hang beneath the track from a harness, legs dangling and are thrown through four 360-degree spiral loops, feet inches from the rock walls. Pure exhilaration. Duration: 1min 30sec Price: Gate price (pounds 16.50 adults, pounds 12.50 children) includes unlimited rides Dangers: Anyone pregnant, or with high blood pressure, heart, neck or back problems should not ride. Originality: 7/10 Fear factor: 7/10 Fun factor: 10/10 Overheard: "My brother said it wasn't that bad - I'll kill him."
The Big One, Blackpool Pleasure Beach: The first drop (235ft) is horrific. So steep is the angle (60 degrees) that riders in the front lose sight of the track and firmly believe the train has run free from the rails and is plummeting at 85mph towards the Prom. Duration: 2min 31sec Price: pounds 3 per ride Dangers: Anyone pregnant or with high blood pressure, heart, neck or back problems should not ride. Originality: 5/10 Fear factor: 9/10 Fun factor: 4/10 Overheard: "Geoff, can we not go on anything else, please?"Reuse content