In the field of security body scanning for contraband and weapons detection, there are multiple technologies currently in use today.
Full body scanner technology is advancing quickly, with units with increasingly sensitive and accurate capabilities being released over the years.
Now there are three types of contraband detection body scanners used by corrections facilities, government facilities, transportation services, and other facilities, each with its own advantages and disadvantages.
1. Transmission X-Ray Scanning Technology
Transmission x-ray body scanners are those that use the same technology as any standard medical x-ray machine does to produce black-and-white x-ray images.
It is favored in many applications as it does not produce an anatomically correct image of the body, while still being able to identify non-human contraband items both on and in the body.
Based on the type of image it creates, transmission x-ray scanning provides suitable accuracy in most circumstances without compromising personal privacy.
Transmission x-ray has quickly become a preferred method for contraband detection body scanners and TSA scanners for their detailed capability while being able to adhere to privacy laws.
2. Backscatter Scanning Technology
Backscatter body scanning uses a more advanced type of x-ray technology that creates an image by bouncing waves off the subject and back toward the unit, creating detailed images of the person being scanned.
It can differentiate between the body and other items to detect contraband on the body, but not within body cavities, so it is not always as accurate for detecting these items.
Additionally, backscatter scanners must be used very judiciously, as they present certain privacy concerns considering the degree of detail produced in the imagery.
3. Millimeter Wave Scanner Technology
Considered the safest scanning technology for delivering the smallest radiation dose of all other types, millimeter wave body scanners work using non-iodizing electromagnetic radiation such as that in a wireless transmitter.
These full body scanners produce a generic body-shaped image with minimal details and can detect contraband on the body, but due to the waves only penetrating within a few millimeters of the surface, cannot detect items within the body or body cavities.
Among all three full body scanner types, the newest models within each type are all considered safe to deliver minimal radiation doses when used as directed.
Based on current privacy laws, backscatter scanners, which were initially introduced into airports by the TSA, have been replaced by transmission x-ray machines.
These machines are now operating more reliably in correctional settings as well.