Editing Extremely high frequency (section)

=== Security screening ===
{{Main|Millimeter wave scanner}}
[[Image:NRW-Verkehrsminister Hendrik Wüst - Vorstellung Easy Security-6274.jpg|thumb|Millimeter wave security scanner at Bonn airport]]
Clothing and other organic materials are transparent to millimeter waves of certain frequencies, so a recent application has been scanners to detect weapons and other dangerous objects carried under clothing, for applications such as airport security.<ref>[http://www.newscientisttech.com/article.ns?id=dn10160&feedId=tech_rss20 Newscientisttech.com]  {{webarchive |url=https://web.archive.org/web/20070311160429/http://www.newscientisttech.com/article.ns?id=dn10160&feedId=tech_rss20 |date=March 11, 2007 }}</ref> Privacy advocates are concerned about the use of this technology because, in some cases, it allows screeners to see airport passengers as if without clothing.

The [[Transportation Security Administration|TSA]] has deployed millimeter wave scanners to many major airports.

Prior to a software upgrade the technology did not mask any part of the bodies of the people who were being scanned. However, passengers' faces were deliberately masked by the system. The photos were screened by technicians in a closed room, then deleted immediately upon search completion. Privacy advocates are concerned. "We're getting closer and closer to a required strip-search to board an airplane," said Barry Steinhardt of the American Civil Liberties Union.<ref name="USAToday">{{cite news |url=https://www.usatoday.com/travel/flights/2009-02-17-detectors_N.htm |title=Body scanners replace metal detectors in tryout at Tulsa airport. | work=USA Today | first=Thomas | last=Frank | date=18 February 2009 | access-date=2 May 2010}}</ref> To address this issue, upgrades have eliminated the need for an officer in a separate viewing area. The new software generates a generic image of a human. There is no anatomical differentiation between male and female on the image, and if an object is detected, the software only presents a yellow box in the area. If the device does not detect anything of interest, no image is presented.<ref name="RobertKane">{{cite web |url=http://www.tsa.gov/assets/pdf/110311_kane_tsa_technology.pdf |title=Statement of Robert Kane to House of Representatives |date=2011-11-03 |page=2 |archive-url=https://web.archive.org/web/20111125014911/http://www.tsa.gov/assets/pdf/110311_kane_tsa_technology.pdf |archive-date=2011-11-25 }}</ref> Passengers can decline scanning and be screened via a metal detector and patted down.<ref>{{cite web |last1=Cortez |first1=Joe |title=The Three Inspection Options at TSA Checkpoints |url=https://www.tripsavvy.com/inspection-options-at-tsa-checkpoints-3259855 |website=Trip Savvy |access-date=11 January 2024}}</ref>

According to Farran Technologies, a manufacturer of one model of the millimeter wave scanner, the technology exists to extend the search area to as far as 50 meters beyond the scanning area which would allow security workers to scan a large number of people without their awareness that they are being scanned.<ref>{{cite web|url=http://www.esa.int/ESA_in_your_country/Ireland/Bat_inspires_space_tech_for_airport_security|title=Bat inspires space tech for airport security|last=esa|website=esa.int|access-date=7 April 2018}}</ref>