Jail body scanners use low-dose transmission X-rays to produce an image of your entire body, inside and out: your skeleton, soft tissue, medical implants, and anything hidden under clothing, swallowed, or concealed in a body cavity. Most correctional facilities now run every arrestee, inmate, and often every visitor through one of these machines at intake and at visitor checkpoints. They’ve largely replaced routine strip searches because they’re faster, less invasive, and catch things a pat-down never would.
What the Scanner Actually Sees of Your Body
A transmission X-ray scan looks like a hospital X-ray. Your skeleton shows up bright white, with individual vertebrae, ribs, and joints clearly outlined. Soft tissue appears as lighter gray shading around the bones. The dose is lower than a medical X-ray, but the anatomical detail is similar, and that detail is exactly what lets operators spot foreign objects: anything that doesn’t match the density of normal human tissue stands out as an anomaly.
Medical hardware shows up prominently. Surgical pins, metal plates, hip replacements, pacemakers, and dental work all register on the image. Trained operators learn to recognize these as legitimate medical items. If you have an implant, it will be visible, but it shouldn’t trigger a secondary search unless its shape or location looks off.
How much of your surface anatomy the operator can see depends on the scanner type. Transmission X-ray images show internal structures without detailed surface contours. Millimeter wave scanners, which some facilities use as a secondary tool, produce a body outline that can reveal surface features like the shape of breasts, buttocks, or genitalia. That distinction matters a great deal for who is allowed to operate the machine, which is covered below.
What Contraband Gets Caught
Transmission X-ray catches a wide range of items. Metallic contraband like improvised blades, razor blades, and handcuff keys shows up clearly because metal is far denser than tissue. The real advantage over a plain metal detector is that the scanner also catches non-metallic items: ceramic blades, plastic weapons, and composite materials all appear as anomalies against your body’s natural background.
Drugs are among the most common finds. Powders, pills, and liquids packaged in baggies or small containers produce visible outlines on the image. This includes drugs that have been swallowed in wrapped packages or inserted into body cavities, which is where transmission X-ray technology earns its reputation. A pat-down or metal detector would miss these entirely.
Cell phones, SIM cards, chargers, and earbuds round out the usual list, along with tobacco products, lighters, and drug paraphernalia. These items are prohibited in nearly all correctional facilities because they can be used to coordinate criminal activity, threaten witnesses, or get around monitored communication systems.
What Scanners Miss
No scanner catches everything. Millimeter wave systems share a fundamental blind spot with surface-only technologies: they can’t see inside the body, so anything swallowed or concealed in a cavity is invisible to them.1U.S. Department of Justice. Contraband Detection Technology in Correctional Facilities That’s why facilities use them as secondary tools rather than primary screening.
Even transmission X-ray scanners have limits. Very small objects, or items designed to match the density of surrounding tissue, can be hard to distinguish. Low-density organic materials present a particular challenge: thin strips of certain plant-based drugs or paper-like substances may not create enough contrast against soft tissue to stand out. Items embedded inside prosthetic devices or made from materials that mimic bone density can also slip past. The scanner is only as good as the person reading the image, and interpretation skill varies with training and experience.
Radiation and Safety
The radiation dose from a single transmission X-ray body scan is very small. The applicable security-screening standard caps the reference effective dose at 0.25 microsieverts per scan.2U.S. Food and Drug Administration. Products for Security Screening of People For comparison, you absorb roughly 5 to 8 microsieverts of cosmic radiation during a cross-country flight. One scan is about one-thirtieth of that.
The FDA also recognizes an annual effective dose limit of 250 microsieverts for individuals undergoing security X-ray screening over a 12-month period.2U.S. Food and Drug Administration. Products for Security Screening of People Even someone scanned repeatedly at intake, transfers, and court returns stays well under that ceiling. Millimeter wave scanners use non-ionizing waves rather than X-rays, so they carry no radiation at all.
Pregnant individuals and people with certain medical conditions may qualify for an exemption from X-ray scanning. Policies vary by facility, but the exemption generally needs to be documented in advance. Visitors who show up without prior approval face a choice: comply with the scan or accept alternative screening with more restricted visit conditions.
Walking Through the Scan
The process is quick. You step onto the scanner platform, place your feet on the marked positions, and hold still. Some systems complete the scan in under four seconds. The X-ray beam passes through you, and the image appears on a monitor in a separate viewing area, where a corrections officer reviews it. You won’t feel anything.
If the image is clean, you move on immediately. If the operator sees something unusual, you’ll face secondary screening: a pat-down, a more targeted scan, or questions about what the operator observed. From stepping on to being cleared, the whole thing usually takes under a minute.
Who Can See Your Scan Image
The Prison Rape Elimination Act imposes real limits on how facilities handle these images. The key question under PREA is how much anatomical detail the scanner reveals. Technologies that produce X-ray-style images without visible body contours can be operated by staff of any gender. Scanners that generate more detailed images showing outlines of breasts, buttocks, or genitalia cannot be operated by opposite-gender staff, because PREA treats that level of visual exposure the same way it treats a strip search.3PREA Resource Center. Does the Use of a Virtual Scanner by an Opposite-Gender Staff Person Violate the Prohibition Against Cross-Gender Viewing
PREA standard 115.15 also prohibits cross-gender strip searches and cross-gender visual body cavity searches except in emergencies or when performed by medical staff, and requires that incarcerated people be able to shower, use the restroom, and change clothes without opposite-gender staff viewing their bodies.3PREA Resource Center. Does the Use of a Virtual Scanner by an Opposite-Gender Staff Person Violate the Prohibition Against Cross-Gender Viewing In practice, because most facilities use transmission X-ray scanners that show skeletal and internal anatomy rather than surface features, there are fewer PREA restrictions on who can operate them.
The scan monitor is kept out of view of the person being scanned. Federal Bureau of Prisons policy explicitly prohibits allowing inmates to see the screen. Image retention is a different story. Some facilities delete images automatically after a set period; others keep them as part of the intake record. There’s no single national standard, so if retention matters to you, ask the specific facility.
Can You Refuse a Body Scan
It depends on who you are. Incarcerated people and new arrestees generally cannot refuse. In Florence v. Board of Chosen Freeholders, the U.S. Supreme Court held that jail administrators may require all arrestees committed to the general population to undergo searches, including visual inspections, without individualized suspicion of contraband.4Justia Law. Florence v. Board of Chosen Freeholders of County of Burlington, 566 U.S. 318 Body scans are generally treated as less invasive than the strip searches Florence authorized, which strengthens the legal footing for mandatory scanning.
Visitors have more room, but the alternatives come with trade-offs. A typical policy offers a choice: submit to the scan or accept a non-contact visit after passing through a metal detector and hand wand screening. Non-contact visits mean physical barriers between you and the person you’re visiting, shorter windows, limits on who can attend, and no physical contact at the start or end. Refusing both the scan and the alternative screening means you don’t get in that day. The restriction usually applies only to the single visit where you decline, not to future visits.
If Something Is Found
Consequences are immediate and serious. For an incarcerated person, contraband detected on a scan triggers a disciplinary process that can include solitary confinement, loss of privileges, and additional criminal charges. Introducing contraband into a correctional facility is a standalone criminal offense in every state, and most states classify it as a felony. Charges can stack: possession of a controlled substance, possession of a weapon, and introduction of contraband can all apply at once.
Visitors face criminal prosecution too, and typically lose visitation privileges permanently. Facilities document the scan image as evidence, and law enforcement is called before the visitor leaves the building. Even an ambiguous image, something that looks suspicious but isn’t clearly illegal, can get you denied entry and flagged for enhanced screening on later visits.
For new arrestees found with concealed contraband during intake, the discovery becomes part of the booking record and can affect bail, plea negotiations, and sentencing. The scan image itself can be introduced as evidence, which is one reason the technology has changed the calculation for anyone considering smuggling something in: it creates a visual record that’s hard to dispute in court.