A file photo of New York City Police Commissioner Ray...

A file photo of New York City Police Commissioner Ray Kelly. (July 13, 2011) Credit: Getty Images

NYPD Commissioner Ray Kelly Thursday touted the blanket of radiation detectors throughout the metropolitan area -- many of which are on Long Island -- as one of the major developments since Sept. 11, 2001, making New York "the safest big city in America."

Some 2,800 radiation pagers carried by NYPD officers -- hundreds more are worn by Suffolk and Nassau police -- and truck-based radiation sensors are guarding the city from a radiological dirty bomb or an improvised nuclear weapon, Kelly told a City Council hearing about the safety of New York 10 years after the terror attacks.

"We are paid to think about the unthinkable," Kelly said after public safety committee chairman Peter Vallone (D-Astoria) raised the issues of germ warfare and other terrorism tactics in his opening remarks.

The detonation of a nuclear device in Manhattan was also the subject of closed-door meeting Tuesday at the Smithtown Sheraton, where more than 150 police, fire and federal officials learned about what would happen after such a blast and the latest thinking on how the public and emergency responders could be protected from fallout. The Suffolk Police Department hosted the meeting.

A key part of the talk was a vivid computer graphic prepared by Brooke Buddemeier, a certified health physicist at the Lawrence Livermore National Laboratory, showing how fallout from a bomb at Times Square could be taken by winds over the rest of New York City and parts of Long Island. A large-scale exercise to detect a fake nuclear bomb is planned for Long Island in December.

"That was the best thing they saw; it really was an eye opener," said Insp. Stuart Cameron, head of the Suffolk County Police Department's special patrol bureau and an expert on nuclear terrorism.

Use of a nuclear bomb by al-Qaida or other terrorists is considered the least likely among terrorist tactics discussed, behind car bombs, radiological "dirty bombs" and poison gas. But the results from a blast comparable in size to the bomb used on Hiroshima would be devastating.

"Low probability, high consequence," Kelly told Newsday last week about the nuclear threat.

A 10-kiloton device would destroy structures in a half-mile-wide zone, severely damage others up to a mile away and blow out glass as far out as 6 miles. Tens of thousands would die.

Police officials and federal experts believe that with planning hundreds of thousands of lives could be saved by alerting the public -- as well as first responders -- how to properly react in the face of radioactive fallout that could cover parts of Long Island, the five boroughs and beyond.

The current thinking is that emergency responders instead of rushing toward the blast site should hunker down in the minutes and hours that follow a detonation to avoid fallout when it is dangerously radioactive, said Dr. Stephen Musolino, a certified health physicist at Brookhaven National Laboratory in Upton.

"Depending on the winds, there may not be a response," at least in the early going, said Chief Robert Ingram, head of the weapons of mass destruction section of the FDNY.

"The first and most important thing is people should seek shelter immediately; that has to be part of a public awareness campaign," Cameron said.

A winter storm is expected to pummel LI as artic air settles in across the region. NewsdayTV meteorologist Geoff Bansen has the forecast. Credit: Newsday

Snow totals may be less across the South Shore A winter storm is expected to pummel LI as artic air settles in across the region. NewsdayTV meteorologist Geoff Bansen has the forecast.

A winter storm is expected to pummel LI as artic air settles in across the region. NewsdayTV meteorologist Geoff Bansen has the forecast. Credit: Newsday

Snow totals may be less across the South Shore A winter storm is expected to pummel LI as artic air settles in across the region. NewsdayTV meteorologist Geoff Bansen has the forecast.

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