Ground zero at the World Trade Center is a landscape like no other, jagged and angular on the surface, with shards of steel piled upon steel. It is caustic beneath from the smoke of subterranean fires. And it is emotional always and everywhere, from the reminders of the lives that were lost.
Those same qualities also make it a work site like no other, and a dangerous one.
Ironworkers, armed with torches and fuel tanks, are held aloft in so-called man-baskets dangling from more than 20 cranes. Steel beams pulled from the debris pile emerge sometimes red hot or with gashes that leave them unstable and prone to snapping.
Goggles, respirators, safety boots and helmets are mandatory. But the protection they provide can be inadequate. Through Sunday, there have been 34 broken bones, 441 lacerations, more than 1,000 eye injuries and hundreds of burns, sprains and smashed fingers since the rescue-turned-cleanup effort began.
From the beginning, there was an overriding emphasis on speed, to search out survivors, and, more recently, to scour the still-smoking debris field for human remains. But increasingly, city officials and cleanup contractors say, there is a push for greater safety.
The urgency of the early days has passed, they say, and while the search for the dead will continue, hazards must be reduced as the long, grinding cleanup extends into winter.
"The risks that were taken early on have to be scaled back," Francis Gribbon, a Fire Department spokesman said. "We can't justify someone else getting killed down there."
The transition from a state of emergency is full of tension. The city's recent decision, for example, to reduce the number of firefighters searching for remains in the ruins sparked an angry protest.
But workaday rhythms rule. Buddies call each other from corners of the pile on their cell phones to check in, and stop together after work for a beer.
Still, there is no escaping the danger, or the strangeness, of the work.
"You can't do much talking all day with a respirator on, so you do a lot of thinking," said Robert Strohschein, a 35-year-old ironworker from Neptune, N.J. "I work with a guy every day. I don't even know his name."
Strohschein, one of 183 workers who have suffered burns at the site, was hurt about two weeks ago when a piece of steel he was cutting burned through his pants.
The extent of danger to workers at ground zero could not be determined independently by the New York Times. Mayor Rudy Giuliani's administration denied repeated requests to enter the site and observe the cleanup work last week.
Though the site is extremely hazardous, inspectors are finding fewer problems as the weeks progress, according to figures from the Occupational Safety and Health Administration.
From Sept. 21 to Oct. 7, for example, OSHA observed an average of 43 site hazards each day, ranging from workers not wearing proper protective gear to dangers caused by improperly stored fuel tanks and cranes that were dangerously assembled. By the last week of October, the number had fallen to 33 a day.
Rates for some injuries have fallen more sharply, according to the New York City Department of Health.
In the first three weeks after the Sept. 11 attack, firefighters, construction workers and others sought medical assistance 6,342 times for injuries that included broken bones, burns and less serious problems like blisters or sprains. In the last three weeks, that number totaled 1,297. The figure included 384 requests for medical attention last week, though none required taking a worker to an emergency room, records show.
The most immediate threat is from the countless physical hazards at the site: hot steel, gas cylinders, unstable debris, cranes swinging back and forth across the skyline.
The other primary threat is not as visible: the toxins that have been measured in the dusty air or the smoke that rises from fires burning deep underground. Physicians say dusts and gases at ground zero have been encountered elsewhere, but never in the sort of mixed form they have taken here.
Work with the cranes is particularly dangerous. The cranes are so tall that frequently their operators cannot see the spot from which debris is being lifted or moved.
One of the most serious accidents at the site happened when a crane cable holding an ironworker in a man-basket became twisted, causing the basket to swing wildly outside its designated zone until it rammed into another crane-operated man-basket. Neither worker was ejected by the impact, but a gas cylinder in one of the baskets broke free and fell onto one of the worker's shoulders, and he was taken to a hospital emergency room.
There has been progress in improving safety.
Inspections last month of the more than 20 cranes
at the site found repeated safety flaws, particularly with the steel cables and slings. Of the 222 crane riggings and slings inspected between Oct. 17 and Oct. 20, 81 had problems, ranging from defective safety latches to worn-out cables, federal officials said.
"That is a pretty high rate of problems," said Patricia Clark, OSHA's regional administrator. "And they are lifting people in baskets with these same riggings."
Inspectors went back last week and found far fewer problems, although Clark said the number was too high.
Crews are steadily moving toward underground work, opening up a whole new set of safety issues.
Firefighters and police officers work at the scene. But instead of large squads of firefighters spread out at different locations, there are often just small groups of emergency workers assigned to each quadrant. Their job is to serve as spotters, looking for and helping collect human remains.
Air testing and monitoring is more or less constant, health and safety officials say. OSHA has fitted some workers with 3-pound kits that attach to their belts with hoses extending up to mouth level; the devices suck in the same air for sampling that the workers are breathing. Scientists from Johns Hopkins University have begun monitoring truck drivers who haul debris from the site, checking for everything from asbestos to silica and dioxins.
For the most part, officials at OSHA say, the risks have been localized in parts of the pile where the smoke plume is greatest. Air samples taken within the plume have contained high mixtures, at times, of compounds like benzene, to which long-term exposure has been linked to anemia and leukemia. But most workers monitored have been found to have little or no exposure to the chemical, OSHA said.
In the first weeks after Sept. 11, many workers and firefighters did not wear proper respirators, leaving large numbers of them with lung irritations, coughs and perhaps even more serious injuries.
And some health experts say that while agencies like OSHA have developed great expertise about individual compounds and chemicals, the mixture that exists at ground zero has no medical or clinical history to help assess exposure risks.
"We're really working in unknown territory," said David Rosner, a professor of history and public health at Columbia University. "We've never had any experience where that incredible mix of chemicals, lead and heavy metals were all crushed under that weight."