Magnetic Resonance Imaging (MRI) uses radio waves and powerful magnets to create detailed images of the body. Because the magnetic field presents a hazardous atmosphere around certain items, MR facilities use an item classification system so that potentially dangerous items are not brought near the MR scanner.
Potentially magnetic items must be tested before entering the controlled access areas of the MR facility. Only items that are proven to be safe near that particular MR environment are allowed inside the MR Suite. When an item is tested, it is classified as MR Safe, MR Conditional or MR Unsafe. Specific icons, usually in the form of stickers, identify the category of each item. These icons may be reproduced in black and white; however, the use of color is encouraged because of added visibility.
MR Safe items pose no known hazards in all MR environments and are indicated by a green and white “MR” icon. Conversely, MR Unsafe items, such as any magnetic item, are unsafe in all MR environments. The MR Unsafe icon features “MR” inside of a red circle with a bar through it. Any items not clearly marked should be considered MR unsafe. Finally, MR Conditional items do not pose any known hazards in a specific MR environment with specific conditions of use. The MR conditional icon consists of “MR” inside of a yellow triangle.
Never bring MR Conditional items into the MR suite without prior approval from the MR staff. Most transports and medical devices will be designated as MR Conditional, so safety within the MR suite depends on knowing what the specific conditions are for each object.
Labeling items and following the MR item classification system helps prevent dangerous situations for both staff and patients within the MR Suite.