With a grinding of saws and a hissing of torches, would-be rescuers from all over California were testing their methods for freeing people from collapsed buildings this week--and found their tools largely slow and inefficient.
“If you had to go through many, many building floors to get people out, you’d be too late,” said Robert G. Curia, a U. S. Navy structural engineer, as he watched firefighters use fancy power tools and just plain brawn to hack through concrete blocks.
This conclusion was not unexpected for members of Urban Search and Rescue, a national group of emergency rescuers and others interested in improving preparation for natural disasters such as earthquakes.
In fact, emphasizing that point was part of the reason the group brought together about 75 California emergency planners, front-line rescue workers, engineers and equipment manufacturing representatives at UC San Diego’s Powell Structural Research Laboratory.
Firefighter rescuers from San Diego, Long Beach, Los Angeles and La Habra took turns Tuesday showing colleagues from throughout the state how they would cut through a 12-inch-thick concrete column or a 6-inch-thick block wall to rescue someone. Their tools ranged from picks and sledgehammers to a state-of-the-art hydraulic ring saw and super-hot torches.
Although the firefighters accomplished those tasks, respectively, in as little as 1 1/4 hours and 17 minutes, their tools still were not as good as they should be, said Frieder Seible, associate director of the UCSD lab.
Seible helped Urban Search and Rescue in recent months to survey the types of equipment available for freeing people from the rubble of collapsed buildings.
“I was very surprised that most of the equipment consisted of simple hand tools--virtually no heavy equipment,” Seible said. “Either you have just simple hand tools or then you have huge equipment like big cranes that can lift basically half the building, but there’s virtually nothing in between.”
Seible noted that this lack of special equipment is what kept a team of California experts, for which he volunteered, from going to Armenia to help with rescue efforts after the Dec. 7 earthquake there that killed 25,000 people.
No Special Equipment
“We more or less had to tell ourselves, ‘Look, the only tools we have to offer the people over there are our hands,’ ” Seible said. “We did not have a piece of special equipment which would have justified sending a team over there.”
Consequently, Seible said, Tuesday’s exercise was intended to show “more the limitations of what we cannot do right now, rather than what we can do.”
This gap is especially important in California as emergency workers prepare for major earthquakes in heavily populated areas of the state, said Mike McGroarty, a fire battalion chief in La Habra and chairman of Urban Search and Rescue.
Although hand tools such as sledgehammers or simple jackhammers can be effective, they just aren’t fast enough, McGroarty said.
“Time is lives,” he said. “That’s the bottom line. How long will it take to get the job done?”
The U. S. Geological Survey has estimated that there is a 60% chance of a major earthquake, of magnitude 7.5 or 8 on the Richter scale in Southern California over the next 30 years. In the peninsular San Francisco area, there is a 50% chance of a quake of magnitude 7, the survey estimates.
Compact, Mobile and Fast
By comparison, the Whittier quake of Oct. 1, 1987, measured magnitude 5.9, and thus released about 1,000 times less energy than a magnitude 7 quake would. (However, the difference in ground shaking would be only a few-fold, since a larger quake is felt over a wider geographical area.)
In a major quake, rescuers need tools that are compact, mobile and fast if they are to save lives, said Capt. Mike Burns, a disaster planner for the Los Angeles Fire Department.
At Tuesday’s demonstration in a plaza between the UCSD Engineering Building and its structures lab--where quake worthiness of building techniques is tested--firefighters were most excited by a ring-shaped hydraulic saw that could cut through 10-inch-thick concrete.
Also garnering attention were “exothermic” torches, which burn at several thousand degrees Fahrenheit and cut through steel reinforcing rods in seconds.
Heavy versions of those machines have become common on construction sites, but remain rare among emergency crews, Seible said.
Burns and McGroarty said Urban Search and Rescue is urging manufacturers to refine such new technologies to create machines portable enough to use in emergencies.