If you are planning to fly over the 4th of July holiday, be aware of your rights at airport security checkpoints.

The Transportation Security Administration (TSA) has mandated that passengers can opt out of going through a whole body scanning machine in favor of a physical pat down. Unfortunately, opting for the pat down requires passengers to be assertive since TSA screeners do not tell travelers about their right to refuse a scan. Harried passengers must spot the TSA signs posted at hectic security checkpoints to inform themselves of their rights before they move to a body scanning security line.

Since the failed Christmas Day bombing of a Northwest Airlines flight by a passenger hiding explosives in his underwear, TSA has accelerated its program of deploying whole body scanning machines, including x-ray scanners, at airport security checkpoints throughout the United States. Scanning machines peak beneath passengers' clothing looking for concealed weapons and explosives that can elude airport metal detectors. So far, TSA has placed 111 scanners at 32 airports. They expect to have 450 scanners deployed by the end of the year at an estimated cost of $170,000 each.

Privacy, civil rights and religious groups object to whole body scanning machines as uniquely intrusive. Naked images of passengers' bodies are captured by these machines that can reveal very personal medical conditions such as prosthetics, colostomy bags and mastectomy scars. The TSA responded by setting the scanners to blur the facial features of travelers, placing TSA employees who view the images in a separate room and assuring the public that the images are deleted after initial viewing.

Yet, a successful Freedom of Information Act lawsuit by the Electronic Privacy Information Center against the Department of Homeland Security (DHS) uncovered documents showing that the scanning machines' procurement specifications include the ability to store, record and transfer revealing digital images of passengers. The specifications allow TSA to disable any privacy filters permitting the exporting of raw images, contrary to TSA assurances.

It begs logic that the TSA would not retain their ability to store images particularly in the event of a terrorist getting through the scan and later attacking an aircraft. One of the first searches by the TSA would be to review images taken by the scanners to identify the attacker.

The Amsterdam airport is using a less intrusive security device called "auto detection" scanning which generates stick figures instead of the real image of the person and avoids exposing passengers to radiation. Three United States Senators recently wrote to DHS Secretary Janet Napolitano urging her to consider these devices. (http://bit.ly/bJFn5K)

More pointedly, security experts, such as Edward Luttwak from the Center for Strategic and International Studies, have come forward questioning the effectiveness of whole body scanners since they can be defeated by hiding explosives in body cavities. The General Accounting Office, an investigative arm of Congress, has stated that it is unclear whether scanners would have spotted the kind of explosives carried by the "Christmas Day" bomber.

About one-half of these body scanning machines use low dose x-rays to scan passengers. Last May, a group of esteemed scientists from the University of California, San Francisco wrote to John Holdren, President Obama's science adviser, voicing their concerns about the rapid roll out of scanners without a rigorous safety review by an impartial panel of experts. The scientists caution that the TSA has miscalculated the radiation dose to the skin from scanners and that there is "good reason to believe that these scanners will increase the risk of cancer to children and other vulnerable populations." (http://n.pr/bKGCKx).

David Brenner, director of Columbia University's Center for Radiological Research, has also voiced caution about x-raying millions of air travelers. He was a member of the government committee that set the safety guidelines for the x-ray scanners, and he now says he would not have signed onto the report had he known that TSA wanted to scan almost every air traveler. (http://www.columbia.edu/~djb3/)

Passenger complaints to TSA and newspaper accounts of passenger experiences with scanners contradict TSA assurances that checkpoint signs provide adequate notice to travelers about the scanning procedure and the pat down option. Travelers, who reported that they were not fully aware what the scanning procedure involved, said they were not made aware of alternative search options. (http://nyti.ms/9hGtU0)

Many travelers complained about their privacy, and their families' privacy, being invaded. Some were concerned about the radiation risk, particularly to pregnant women and children. Some travelers felt bullied by rude TSA screeners. The Wall Street Journal reported that one woman who refused to go through the body scanner was called "unpatriotic" by the TSA screener.

Expensive state-of-the-art security technology that poses potentially serious health risks to vulnerable passengers, invades privacy, and provides questionable security is neither smart nor safe. For the White House it is a political embarrassment waiting to happen.

President Obama should suspend the body scanning program and appoint an independent panel of experts to review the issues of privacy, health and effectiveness. After such a review, should the DHS and TSA still want to deploy body scanners at airports, they should initiate a public rulemaking, which they have refused thus far, so that the public can have their say in the matter.

If you experience any push-back from TSA screeners when you assert your right to refuse to go through a whole body scanner and request a pat down security search instead, please write to info@csrl.org.

Ralph Nader is a consumer advocate, lawyer, and author. His latest book is The Seventeen Solutions: Bold Ideas for Our American Future. Other recent books include, The Seventeen Traditions: Lessons from an American Childhood, Getting Steamed to Overcome Corporatism: Build It Together to Win, and "Only The Super-Rich Can Save Us" (a novel).

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