Some time ago, a client consulted us about a medical device with metal parts that was already on sale in several markets. The company had always focused on routine items such as biocompatibility, sterilization, packaging and performance testing.
Until an overseas customer asked during a technical review: “Can this product be used in an MRI environment? Does the IFU include an MR Conditional statement?”
Only then did the company realize that although its product is not an MRI device, if it may be carried into an MRI examination by a patient or may enter an MRI scanner room, a dedicated MRI safety assessment may be required. Such issues are very common for implants, orthopedic products, stents, catheters, electrodes, monitoring accessories, external fixators and other devices with metal or conductive parts.
MRI stands for Magnetic Resonance Imaging. Many people think of MRI as the large scanner in a hospital. But from a safety assessment perspective, the MR environment is not just inside the scanner bore; it includes the area around the MRI system affected by the strong magnetic field, radio-frequency field and gradient fields.
This environment differs from ordinary use environments, with risks coming mainly from three sources:
First, the strong static magnetic field. If a product contains magnetic materials, it may be attracted or moved, even creating a “projectile” risk.
Second, gradient magnetic fields. These may induce currents, vibration or local heating in metal parts.
Third, the radio-frequency field – the part many implants most need to consider. Conductive materials in the RF field may experience RF-induced heating, causing a local temperature rise in tissue.
So whether a product can safely enter the MRI environment cannot be judged simply by “does it contain metal” or “is the material stainless steel”; it must be assessed taking into account the product’s structure, size, materials, location of use and labeling.
2. Which Products Need to Consider MRI Safety?
Generally, the following products need particular attention:
Implantable products, such as bone plates, screws, stents, clips, artificial joints and heart valves.
Semi-implanted or patient-contacting products, such as catheters, external fixators, electrodes and sensors.
Active medical devices, such as pacemakers, neurostimulators, infusion pumps and monitoring equipment.
There are also external devices that may enter the MRI scanner room, such as trolleys, monitors, anesthesia equipment and infusion equipment. These products don’t all need the same tests, but companies should at least first determine: might the product enter the MR environment? Does it contact the patient? Does it contain magnetic, metallic or conductive materials? Does it have circuits, cables, electrodes or sensors?
3. An MRI Label Is Not Just Writing “Compatible”
Internationally, MRI safety labeling is usually not simply “MRI compatible”. The more standard terms fall into three categories:
First, MR Safe: the product poses no known hazards in the MR environment. Usually only non-metallic, non-conductive, non-magnetic products can qualify.
Second, MR Unsafe: the product poses unacceptable risks in the MR environment and must not enter it.
Third, MR Conditional – the most common category. It means the product can be used safely in the MR environment only under specified conditions.
For example, the label may need to state clearly: whether it applies to 1.5 T or 3.0 T fields; SAR or B1+rms limits; scan duration; whether a cooling period is needed; which coils are used; the product’s position in the body or scan region; and the approximate extent of image artifacts.
So MR Conditional is not a marketing slogan but a set of conditions of use supported by testing or scientific justification.
4. What Are the Common MRI Safety Tests?
From a medical device perspective, common tests include the following.
First, magnetically induced displacement force testing: whether the product is attracted and moved in the strong field. The common standard is ASTM F2052.
Second, magnetically induced torque testing: whether the product rotates or twists in the field. The common standard is ASTM F2213.
Third, RF-induced heating testing – the most critical item for many metal implants and conductive devices. The common standard is ASTM F2182.
Fourth, image artifact testing: whether the product affects MRI image quality. The common standard is ASTM F2119.
Fifth, functional assessment of active devices. If the product has a power supply, circuits, software, sensors or electrodes, you must also consider whether the MRI environment could cause malfunction, functional anomalies, data errors or performance degradation.
5. Why Is RF Heating Often the Hardest Part?
Many companies ask: my product’s materials are already decided, so why do RF heating? Because RF heating is not determined by materials alone.
It depends on the product’s length, geometry, surface condition, conductive paths, electrical contact between components, implantation site and scan conditions.
For example, among stainless steel products, elongated structures, pointed tips and multi-component assemblies may behave completely differently in the MRI RF field. Some lengths may approach the resonant dimensions of the electromagnetic field, leading to a more pronounced local temperature rise.
Therefore RF heating assessment usually cannot rely on experience alone and needs to be supported by testing, numerical simulation or sufficient scientific justification.
6. Does Every Model of a Multi-Size Product Need Testing?
This is also companies’ biggest cost concern.
For multi-size, multi-component products such as orthopedic and stent systems, testing every length, size and combination would be very costly and time-consuming.
The FDA’s approach is not to require companies to test every combination, but to build a product matrix first and then select the worst-case combinations scientifically.
Selection usually considers:
Which size is most likely to heat; which structure is least favorable; which material combination carries the highest risk; which component connections would create conductive paths; and which combinations are realistically possible in clinical use.
Numerical simulation is very valuable here. It can model the electromagnetic field, SAR distribution and temperature distribution, helping companies find the most representative worst cases before arranging actual tests.
But note that simulation is not just building any model. For registration or technical documentation, a sound method description, validation data and uncertainty analysis are usually also needed.
7. What Should Companies Prepare in Advance?
If your product may involve MRI safety, we recommend preparing the following information early:
Product structure drawings, material lists and model/size tables; whether it contains metal, magnetic or conductive materials; whether it is implanted, contacts the patient or may enter the MRI scanner room; whether it has circuits, cables, electrodes or sensors; all sizes and possible combinations; whether you want the final label to say MR Safe, MR Unsafe or MR Conditional; and whether the target is the US FDA, EU MDR, or hospital procurement or customer acceptance requirements.
The earlier this information is ready, the easier it is to control testing costs and registration timelines.
8. Who Needs to Think About MRI?
MRI safety is not just a concern for MRI equipment makers.
For medical device companies, as long as a product may enter the MR environment – especially if it contains metal or conductive materials, is implanted or contacts the patient – the related risks should be assessed early.
The most common mistake is to write simply “can be used with MRI” or “MRI compatible” in the IFU without clear test evidence and conditions of use. A more sound approach is to determine, based on the product’s actual structure and intended use, which tests are needed and whether worst-case selection can reduce the number of tests, and ultimately produce a clear MRI safety label acceptable to regulators and hospitals.
Simply put, MRI safety testing is not a standalone project but part of product risk management, registration documentation and IFU labeling. Planning ahead is usually cheaper than fixing things later, and makes customer and regulatory reviews easier to pass.
How Can EVERBIZ Help?
For medical devices with MRI safety requirements, companies often need more than a single test: they first need to determine whether the product actually enters the MR environment, how the target label should be stated, which risks need verification, and which models can be covered through worst-case selection to reduce testing.
Based on your product’s structure, materials, models and intended use, EVERBIZ can help design an MRI safety assessment plan, including determining the MR Safe, MR Unsafe or MR Conditional labeling route, confirming test items, mapping the product matrix, analyzing worst-case combinations, and planning tests for RF-induced heating, magnetic displacement force, torque and image artifacts.
For multi-size, multi-component or structurally complex products, EVERBIZ can also coordinate numerical simulation resources to analyze electromagnetic field, SAR and temperature distributions and select more reasonable worst-case combinations, reducing unnecessary repeat testing costs.
EVERBIZ can also help prepare supporting documents for registration and technical documentation, including MRI safety risk analysis, test plans, test report review, writing MRI labeling for the IFU, compiling MR Conditional conditions of use, and technical explanations for FDA, EU MDR or customer audits.
Simply put, we can help turn MRI safety from “a test requirement a customer suddenly raises” into an executable, explainable compliance plan usable for registration and market access.
EVERBIZ Certification Services (Shanghai) Co., Ltd. (EVERBIZ) is a professional compliance service platform for testing, certification, consulting and training of medical products, dedicated to helping leading medical R&D companies at home and abroad improve their compliance capabilities and competitiveness. The company has offices and branches in Shanghai (China), Hong Kong, Munich (Germany), Salzburg (Austria), Thailand, Vietnam, Singapore and Malaysia, covering nearly 25 industries of compliance products (such as medical devices, new energy, household appliances, lighting, tools, laboratory instruments, machinery, in vitro diagnostics, wireless products and reagents).
Shanghai: Room 909, Building 1, Lane 111 Luxiang Road, Baoshan District, Shanghai, China; Germany: Landsberger Str. 155, 80687 München, Germany
Austria: Innsbrucker Bundesstraße 136/3, 5020 Salzburg, Austria
Hong Kong: Room A1, 11/F Winner Building, 36 Man Yue Street, Hung Hom, Kowloon, Hong Kong
Thailand: No. 850 Soi Lat Krabang 30/5, Lat Krabang Subdistrict, Bangkok 10520
