As casually as corporate executives knot their ties in the morning, police officers in New York City's Emergency Service Unit (ESU) strap on 40-pound bulletproof vests.
They are as at ease with a 12-gauge long-barrel shotgun propped on their hip as a Central Park jogger might be clipped to a Sony Walkman. When they show up wearing the unit's distinctive blue baseball cap, professional criminals know it's not a Mets ballgame.
A police writer says about them that if King Kong ever did climb to the top of the World Trade Center with a ladyfriend, somebody in Emergency Service would be ''handed a rope and told to chaperon.''
If there's a prison riot, a hostage taking, or a terrorist threat anywhere on the richest piece of real estate on Earth, the nation's premier SWAT (special weapons and tactics) team, Emergency Service, will be there.
But here the hero-hype ends and the extraordinary inner strength and resolve begin.
Even though their official arsenal - antisniper rifles, Uzi submachine guns, carbines, armored personnel carriers (Korean-war vintage) - does honor to the memory of John Wayne, at Emergency Service there is no praise for being macho. The KGB may covet some of their special equipment; nevertheless the TV SWAT-team image is all wrong.
'' 'Sentimental, compassionate, concerned, committed, emotionally strong but tender, mature, family man.' These are the kinds of words we use when we interview a man wanting to join Emergency Service,'' says Daniel A. St. John, deputy inspector and commanding officer of ESU. ''We give out medals for not firing your gun. We want somebody who has been thinking maturely and practically before he gets here.''
The ballistic statistics back up Inspector St. John's words. Responding to more than 3,500 incidents last year in which the perpetrator was armed, they fired only twice. No one was killed.
''Our philosophy is protection for everybody involved: the victim, ourselves, and the perpetrator,'' says Frank Gallagher, second in command to St. John.
* It's early September, and just across the East River from Manhattan, the northbound traffic is light on the Brooklyn-Queens Expressway.
''I've been in Emergency Service 15 years and I've never seen two jobs the same,'' says Sgt. Al Baker, driving a blue and white ESU van. ''Guys in this unit would rather be given a pick and shovel and told to tear into a building looking for evidence, get to someone behind a barricade, than push a pencil and paper.''
The newest addition to ESU sits in the rear of the van, a four-wheeled robot with the capability of remote observation for barricade situations. ''We can send it into places where we think there may be radiation or chemical leaks as well,'' says Sergeant Baker.
Tersely, calmly, a police dispatcher's voice over the van's radio reports that the cable on a crane at the Brooklyn Navy Yard has snapped. Three men are trapped underneath scaffolding in Dry Dock 6.
Baker automatically reaches for his blue baseball cap, changes lanes, and exits the expressway. ''There's always a back way in Brooklyn,'' he says.
As we speed to the Navy Yard, he thinks out loud. ''What do I need to get to those men under heavy metal? High-powered jack, acetylene torch, stretchers. If I don't have much time, what I bring with me can make all the difference.''
* In the Big Apple, when a cop needs a cop, he calls Emergency Service.
The unit responds to more than 50,000 emergency calls a year, most initiated by other police officers. Anything from guarding Fidel Castro at the UN, talking a jumper off a roof, and collaring an escaped chimpanzee at the Bronx Zoo to freeing someone trapped beneath a subway car. It's all in a day's work.
An ESU candidate needs a minimum of three years' experience in a high-incident precinct before he can apply for one of the 280 citywide positions.
''Joining is like taking marriage vows,'' says St. John. (Formerly a regular officer at the notorious Fort Apache precinct in the Bronx, he was eligible for retirement 16 years ago, but ESU is where he wants to be.) ''You have to be a team player. The first year's probation proves this out - that, and the training.''
A recruit's first introduction to specialized marksmanship communicates the department's philosophy for life saving.
* Be the best shot on the firing range so you can hit an armed criminal or a terrorist who has taken hostages.
* Learn barricade strategy so you never have to fire a shot.
* Trust that the other guy knows how potent but disciplined your firepower is.
But always there is the commitment to ''take care'' as well as to ''take action,'' and immediately after their tour on the firing range, they receive three weeks of emergency medical training (EMT).
Helen Knedlhans, RN, is the only woman in Emergency Service. The daughter and sister of police officers, she is in charge of EMT. From the outset it is clear the value placed on her instruction ranks higher than marksmanship. ''We want them to know we're here to save lives,'' she says.
A hiring freeze caused by New York's fiscal crisis in 1975 limited the number of women on the NYPD. Officer Knedlhans fully expects that as soon as the women who have been recruited in recent years have completed their three years of precinct duty, they too will join the ranks of Emergency Service officers.
Emergency Service training is unlike anything in police work. Hundreds of other police departments as well as the FBI and the Secret Service have taken courses offered by this New York Police Department ESU staff.
It includes lessons on how to repair downed electrical wires and poles and how to operate heavy construction equipment (including the unit's own armored personnel carrier).
They learn what they call the art of extraction - freeing people trapped in elevators, in jackknifed tractor trailers, and in building cave-ins. ''We look at an applicant to see if he has any special building-trades skills,'' St. John says.
Special instruction is given on what to do in radiation accidents, as well as in handling explosives. When Manhattan's garment district lost its electricity recently, ESU teams were there with generator trucks and special searchlights.
One of the emergency team's most difficult training focuses on how to handle ''the real orphans'' of the city - the jumpers, says Gallagher. He speaks of potential suicides.
''There's no way you can convince a policeman to wrestle with a jumper on a 12-inch ledge of the World Trade Center unless he has some kind of values,'' says Mr. Gallagher. ''We're the only ones, and maybe the last ones, out there with him.''
For Sergeant Baker, the greatest thrill of his career was commanding the squad that brought a man down from the top of one of the World Trade towers.
* Extricating and then safely placing the three injured Brooklyn Navy Yard men on stretchers completes the assignment for Baker's team and five other ESU officers. They watch as a crane hoists the men to waiting ambulances.
Later that night, in a different car with a different officer across the river in Manhattan, the subject of jumpers comes up again. The radio interrupts: ''Potential jumper on top of Macy's department store.'' Through the eyes of a cop, New York City can look like the biggest orphanage in the United States.
''When a person climbs out on a ledge, we're the only ones left in their lives,'' says Lt. Larry Savage.
''You don't want to think too much about details when you respond to a call, '' he says. ''If you get too rigid a mind-set . . . , you may not respond to what actually needs to be done.''
''But that roof (at Macy's) is not open to the public,'' says the 27-year veteran of ESU, who in his career has been on top of most of the city's high roofs. ''It would have to be an employee . . . ,'' Savage says. His hunch is right. It's the first of three such false alarms this shift.