Fearing that the nation's ports are vulnerable to an underwater attack, the United States Coast Guard is extending its domestic law-enforcement mission into a new arena: the sea below.
The Coast Guard's new tools include a new sonar-based device that can distinguish humans from aquatic life and underwater weapons that are being developed, including an air gun that sends a nonlethal acoustic impulse to force divers to surface by causing them discomfort, officials said.
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After the 2001 terrorist attacks, the Federal Bureau of Investigation asked the nation's largest organizations that certify scuba divers to turn over records of every diver certified in the United States for the last three years. The extension of Coast Guard patrols underwater surprised leaders of groups that represent diving professionals. Jeff Nadler, vice president of PADI Americas, the world's largest diver certification organization, said on Tuesday that he was disappointed that his group had not been consulted.
"We certainly are very supportive of the need to take appropriate steps to protect the public against terrorist activities," Mr. Nadler said. "But what is the impact of high-frequency sonar on a individual who is diving? At this point, we don't know."
http://www.nytimes.com/2005/02/02/national/02ports.html?ex=1265086800&en=9f35216b4847dc88&ei=5090&partner=rssuserland