PUBLISHED : Sunday, 13 December, 1998, 12:00am
UPDATED : Sunday, 13 December, 1998, 12:00am

FOR decades, Earth's highest peaks have beckoned climbers with their siren songs. Some stand on summits triumphant; others end up human iceblocks. Many cannot explain the urge to haul themselves to the roof of the world, and laugh off their exploits with a vague 'because it was there'.

Now, a similar mentality seems to have gripped the collective psyche of a growing section of the diving world. Where most were previously content to potter around reefs blowing bubbles at lurid-hued fish, now it is a race to see how low you can go.

Technical diving is the new buzzword for those who like to get down. Its adherents risk decompression sickness, nitrogen narcosis and other more rare but equally nasty side-effects in their quest to boldly go where no man - and few fish - have gone before.

Detractors say it is bad for the sport's image - the metier of macho maniacs who are doing their best to make manifest the alternative explanation for the acronym SCUBA - Sometimes Come Up Barely Alive. Supporters say the only accidents happen to people who do not bother to do the training, and claim far more recreational divers die than do 'techies'.

The death of Sir Run Run Shaw's granddaughter, Shaw Soo-ling, and her Dutch friend Philip Lemette, off the Anambas Islands in Indonesia in June has heightened the debate in Asia. The pair died after diving to 80 metres, twice the limit to which recreational divers using normal air are supposed to descend.

IT was later revealed that Shaw and her sister, Soo-wai, had signed up for a technical diving course a month earlier - but never got beyond the first theory lesson. Soo-wai survived the dive, but has refused to speak of the ordeal.

Technical divers are quick to point out the trio had been diving on normal air, so there was nothing 'technical' about the dive. Rather, it was a classic example of what happens to divers who defy accepted safety standards. But some in the sport believe the craze for going deeper means their deaths will not be the last.

Paul Neilsen, who runs Mandarin Divers at Aberdeen, is a veteran of many deep dives. His piercing eyes glint and his moustache bristles when the deaths of Shaw and Lemette are mentioned in the same breath as technical diving.

'What they were doing had nothing to do with technical diving and that's that,' he says. 'In my experience, the people who carry on with all the macho rubbish, you know, I've been this deep - they are the people who aren't trained. You get some instructors or dive masters, or experienced recreational divers who'll carry on with that. Fine. I'm not going to engage in a conversation at that level. If that's the way you want to dive, it's your business.' Mr Neilsen says the main benefits of technical diving are allowing divers to go deeper and stay down longer, enabling them to explore caves and wrecks that previously were off-limits. They use special blends of gas that counter the effects of decompression and nitrogen narcosis - the so-called 'rapture of the deep', a similar state to being drunk.

As divers go past 40 metres, the compressed air in their scuba tank becomes increasingly toxic. Diving to 80 metres on compressed air would be like having 16 stiff drinks in a matter of minutes - hardly a state in which to be making rational decisions. Skin Diver magazine describes going past 40 metres using conventional scuba apparatus as 'insane' and 'irresponsible'.

Mr Neilsen says no one from Hong Kong has died from technical diving. Dive scene insiders, however, say he was 'pretty shaken up' by the death of Norwegian friend Harald Kvam while they were doing a deep dive off Papua New Guinea in April. Kvam, 41, had worked in Hong Kong since the 80s, using his diving skills to maintain shark nets, among other business ventures.

Hong Kong Underwater Association (HKUA) vice-chairman Chin Kam-wing says the group is keeping a close watch on the boom in technical diving.

'At the moment, the HKUA is keeping an open eye on the market trend and evaluating the safety and procedures of any underwater sports before promoting it,' Mr Chin says. 'We have no intention to promote technical diving to the recreational diving population of Hong Kong at this stage. For reasons of safety, we will not recommend that any of our member divers make any deep dives.' Editor of Action Asia magazine, Robert Houston, says the advent of technical diving has split the sport. 'A lot of the tech-heads think recreational divers are wimps, and recreational divers think the tech-heads are pretty weird,' he says.

'Once you get beyond the recreational limits, you're talking about a lot of planning. It's not for people who just want to look at coral and fish. You are risking your life and when you get down very deep, there's probably not much to see anyway except an empty sea bed.

'I can understand the attraction if it's to explore a wreck but some people are into going deeper for the sake of going deeper. The macho element is the dangerous part. Most people dive to relax, not to risk their lives. Whatever the attraction is, though, there is no doubt it is becoming more and more widespread.' Asian Diver editor Julie Goh agrees the sport is picking up throughout Asia. She describes it as 'a world apart' from recreational diving. 'There are two totally different camps,' she says. 'Technical divers are usually pretty seasoned, gung ho and well and truly into their equipment. For recreational divers, it's more about the trip, the food, the travel.' Singaporean Gideon Liew, a member of the International Technical Diving Institute, is the technical diving instructor who gave the Shaw sisters their first and only theory lesson before their ill-fated dive.

'Soo-ling was at one time a student of mine,' Mr Liew says. 'She enrolled to do a basic nitrox course with me, with the objective of being able to do extended-range diving and penetrating wrecks. The sisters were clear that they wanted to dive deeper and they were keen to learn the right way. They knew diving deeper required further training.

'But she only came to the first class before embarking on her trip. My opinion is that it's a personal choice. You cannot stop someone from taking foolish risks.' He says the effects of nitrogen narcosis meant people lost their sense of danger sometimes and became almost mesmerised by the world they entered, going deeper and deeper until there was no chance of survival.

'I was pretty upset by what happened. I told them specifically what there was to learn if they wanted to go beyond 40 metres. Maybe they got impatient. I know Philip [Lemette] was a dive instructor with a lot of experience in the water, you would not say he was gung ho. He was always a cautious diver, although he could have had a change of attitude.' Mr Liew says he has spoken to Soo-wai since the tragedy. 'She says she encountered severe narcosis trying to get out of there. She was with Soo-ling and Phil when they began having problems with narcosis. When she began her ascent, her dive computer had registered 84 metres. They were supposed to come up together, but she lost the others during the ascent. She is distraught, of course. But the safety limits are there for a reason and you cannot ignore them.' Mr Houston says going to 80 metres on normal air is suicidal. 'That's totally against all the principles you are taught,' he says. 'The deepest you can go on normal air is 50 metres, and even then you can only stay at that depth for about four minutes. It might have been a case of their getting hypnotised by the narcosis. There were a couple of Taiwanese guys who disappeared off Sipidan [off Sabah]. They became mesmerised and just kept going deeper. Their instructor couldn't do anything about it.' Singapore Underwater Sports Federation president Sydney Chew says the Shaws and Lemette were diving at an abandoned oil rig in 'very deep-water and hostile conditions'.

He says the federation is working with the Singapore Government on penalties for instructors who allowed deep-diving without proper instruction. 'They went beyond the limits. I hope we can learn from this,' he says.

DIVERS do not come much more technical than Mr Neilsen. The walls of his office are festooned with certificates and qualifications from the International Association of Nitrox and Technical Divers and other deep-diving groups.

He explains the technical side of technical diving. The most common blend of gas used is Enriched Air Nitrox, which is richer in oxygen than normal air. He says as divers go deeper, their air is used up more quickly. The limit for divers using nitrox is still 40 metres, but they can stay down longer.

'All this got started in the late 1980s. When they first tried to introduce nitrox into recreational diving, there was a general backlash. So it took a few years to be accepted, then a few more years to become popular,' he says.

'For example, when we breathe normal compressed air, we can go to, say, 18 metres for about 50 minutes. If we get a better mix of air - nitrox - we can almost double that time. It allows you to go longer, not deeper,' he says.

'Everyone has their own view of what 'technical' means. My view is that it is anything beyond the recreational limits. For example, there are ways you can dive to 50 metres on air, then use nitrox for decompression. Recreational diving doesn't allow decompression.

'Decompression-diving is when you stay down longer than the recommended time, then you have a staged ascent, where you stop for a period of time at set points. That gives your body a chance to get rid of the nitrogen bubbles in your blood so you don't get decompression sickness [the bends].' This is where it does start to get technical, and Mr Neilsen concedes that, when pushing the limits, the margin for error is tiny, so preparation and back-up plans are vital.

The next step from nitrox is to trimix and rebreathers, and here we are well and truly in boffin land. Divers at this level have so many tanks and gadgets hanging off them that they probably look to the normal recreational diver like the Creature from the Black Lagoon.

Trimix is a blend of nitrogen, oxygen and helium, which allows divers to go to 60 metres and beyond. Rebreathers are closed-circuit systems, which retain the diver's exhaled air, using 'scrubbers' to clean it of carbon dioxide. Small amounts of pure oxygen and inert gases, controlled by sensors, are injected to maintain volume.

Mr Neilsen says rebreathers have the added advantage of being quiet - there are no noisy jets of bubbles to scare marine life away, making it ideal for deep-water photography.

He says about 10 per cent of his dive students go on to technical diving. 'For technical nitrox, we have three instructors, including myself. At trimix level, there's only one, that's myself. At rebreather level, there's only one, that's myself. At technical rebreather level, there're only three in the world and I'm one of those guys.

'Some of these courses, you need 400 dives just to get in.' It is not a sport for the poor - he says a 10-day trip to dive wrecks would cost around US$10,000 (HK$77,400).

IT is unlikely that June's deaths will deter trained technical divers from pursuing their quest to go deeper. The month before, two dive instructors broke the Philippine deep-diving record. John Bennett and Aaron Gilespie made it down to 122 metres and plan to go deeper.

Their goal was to find The Abyss, an almost-bottomless chasm some divers have glimpsed near Escaria Point, a recreational dive site. Mr Bennett told Action Asia that at extreme depths his senses sharpen 'and when you surface, everything seems clearer'. He says he has 'complete respect for the sea, the most powerful force in the world'.

Their dive was not even close to the world record. American Jim Bowden went down to 276 metres in 1994 at Zacaton, a water-filled cave in Mexico's central eastern state of Tamaulipas. Mr Bowden described it as 'the last frontier'. It certainly was for his partner, Sheck Exley, who never made it back.

Has Mr Neilsen had any close shaves? 'All the time. Ha Ha. I've had some heart-stopping moments, but then again when you drive around Hong Kong you have some heart-stopping moments.

'What do I get out of it? Adventure keeps me diving. It's in your blood.'