Elite rescuers who specialise in saving people trapped high above the city's pavements are switching their focus below ground.
The Fire Services Department's High Angle Rescue Team is preparing for the possibility that it might be called on to save workers in one of several subterranean projects now under way in Hong Kong.
The team, formed in 2011, already knows underground work can be much more daunting than high-level rescues: its training includes both. But it has never been called on to carry out a belowground rescue before.
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"When you're up high you can see a long way and the scenery has a comforting effect," said senior fireman Rambo Chow Koon-ho, 44. "But when you go underground, the claustrophobic feeling can get really intense; when you look down, the only source of light is no brighter than a candle. It sends a chill down your spine."
The term "high angle" refers to the rescues the team carries out - at places with a gradient of 60 degrees or more, above or below ground, where only firemen with special training can operate comfortably. Saving people trapped as deep as 160 metres below sea level has been part of the team's regular training.
It is usually based on construction workers trapped deep below ground after blasting or excavation goes wrong.
"Usually these sites have elevators, but there is no better substitute for men [to get people out] if machines break down," Chow said.
Most underground construction now under way takes place at MTR rail projects, including the cross-border high-speed railway, the Sha Tin-Central link and the West Island Line.
Among the many missions he has undertaken, fireman Chan Shu-tung, 34, said saving two window cleaners trapped in a gondola stuck on the 20th floor of a famous hotel was particularly unforgettable. "We ended up bringing the two workers to the presidential suite since it was the closest room" to where they were trapped.
"It's a shame that I didn't have time to take a better look at the room."
The 40 team members, aged 29 to 53, are also regular firefighters stationed at Pok Fu Lam Fire Station on Hong Kong Island and Tin Sum Fire Station in Sha Tin.
The team is now considering the possibility of expanding the unit and has an extra team stationed in Kowloon.
"But that doesn't mean we will lower our entry requirements," said team leader Choi Kwok-chung, adding that during the team's recruitment exercise before it was established, just 55 of 400 applicants met the strict entry standards.