TSA’s test for explosives picks up harmless residue
Question: I went on a day trip to Hilo, and upon my return, even with a TSA Precheck boarding pass, the Transportation Security Administration agent asked to see all my electronic devices.
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Question: I went on a day trip to Hilo, and upon my return, even with a TSA Precheck boarding pass, the Transportation Security Administration agent asked to see all my electronic devices. She took my cellphone and Kindle to a machine and said it tested positive. When I questioned what she meant, she said it tested positive for explosives, and I had to go through a pat-down and my handbag and backpack were completely emptied and inspected. What else could have caused this erroneous reading?
Answer: Many everyday products contain either nitrates or glycerin, two bomb-making compounds for which the TSA screens and which also may be present in harmless items, scientist and author Anne Marie Helmenstine explained in a column for ThoughtCo. last year (808ne.ws/glycnit).
The TSA’s tests are highly sensitive for trace amounts of explosive residue, she wrote. Among the products that can cause a positive result are:
>> Hand soaps and/or lotions that contain glycerin.
>> Cosmetics and hair products, which might contain glycerin.
>> Baby wipes, which might contain glycerin.
>> Certain medications, such as nitroglycerin and other nitrates.
>> Lawn fertilizers that contain nitrates.
>> Fireworks and other pyrotechnics.
“Sometimes you won’t have any idea why you flagged the test. But, careful attention to hygiene may help you avoid the situation,” she wrote, advising travelers to rinse thoroughly after washing hands and to clean their shoes before heading for the airport.
As for security in general: The TSA announced stricter screening of electronics, beginning last summer in a few airports and phased in across the country by the beginning of this year. The new rules require travelers in standard security lines to remove all electronics larger than a cellphone from their carry-on bags and place them in bins, with nothing atop or below the devices, so that screeners can obtain a clearer X-ray image. This is how laptop computers have been screened for years.
However, the stronger security measures do not apply to passengers enrolled in TSA Precheck who are using TSA Precheck lanes, according to the agency. Hilo International Airport is among 200 U.S. airports that offer TSA Precheck, so we’re not sure why you were singled out. Perhaps you used a standard security line, rather than one designated for TSA Precheck?
The TSA also emphasizes that enrollment in TSA Precheck does not guarantee quick passage through checkpoints. “TSA uses unpredictable security measures, both seen and unseen, throughout the airport. All travelers will be screened, and no individual is guaranteed expedited screening,” it says on its website.
We found online forums brimming with complaints from TSA Precheck members subjected to unexpected searches. Based on remarks there, it could be that you were chosen at random for what would have been a quick check if the swab test had been negative, but progressed to a full search of your belongings because it was not.
To the four guardian angels who came to my husband’s aid when he dropped his motorcycle at the King Street exit off the H-1. Three compassionate men (professor Mills and I forgot the other two names) took such great care calling 911, getting him a drink, wrapping him in towels, getting his bike out of the street and waiting with him until the EMTs arrived. You all were so wonderful! Mahalo also to David, who sat with him while he waited for the tow truck. Not to be forgotten, mahalo to the EMTs and the HPD, who came and cared so quickly and well, as always. We’re so grateful. — C. & E.W.
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