Contains Nonbinding Recommendations
Testing and Labeling Medical 
Devices for Safety in the Magnetic 
Resonance (MR) Environment
Guidance for Industry and Food and 
Drug Administration Staff
Document issued on October 10, 2023.
Document originally issued on May 20, 2021
For questions about this document, contact the Office of Science & Engineering Laboratories 
(OSEL), OSEL_CDRH@fda.hhs.gov, (301) 796-2530. 
U.S. Department of Health and Human Services
Food and Drug Administration
Center for Devices and Radiological Health Contains Nonbinding Recommendations
Preface
Public Comment
You may submit electronic comments and suggestions at any time for Agency consideration 
to https://www.regulations.gov. Submit written comments to the Dockets Management Staff, 
Food and Drug Administration, 5630 Fishers Lane, Room 1061, (HFA-305), Rockville, MD 
20852-1740. Identify all comments with the docket number FDA-2019-D-2837. Comments 
may not be acted upon by the Agency until the document is next revised or updated.
Additional Copies
Additional copies are available from the Internet. You may also send an e-mail request to 
CDRH-Guidance@fda.hhs.gov to receive a copy of the guidance. Please use the document 
number GUI01500059 and the complete title of the guidance in the request. Contains Nonbinding Recommendations
Table of Contents
Introduction  1 
  Scope  2 
  Terminology  2 
  Relevant Consensus Standards and Guidance Documents  4 
 Consensus Standards  4 
  Guidance Documents  5 
  Addressing Hazards for Medical Devices in the MR Environment  5 
 Magnetically Induced Displacement Force  6 
  Magnetically Induced Torque  7 
  Heating  8 
 Gradient Induced Vibration  11 
  Gradient Induced Extrinsic Electrical Potential (Unintended Stimulation)  12 
  Rectification of RF pulses from MR Exams (Unintended Stimulation)  12 
 Medical Device Malfunction  12 
  Extent of Image Artifact  14 
  Reporting Results  15 
 MRI Safety Labeling  16 
 MR Safe 18 
  MR Unsafe 19 
  MR Conditional  19 
 Safety in MRI Not Evaluated  23 
Appendix 1. Example of Test Result Summary that may be Included in a Regulatory 
Submission  25
Appendix 2. MR Conditional Labeling Examples  26 Contains Nonbinding Recommendations
Testing and Labeling Medical 
Devices for Safety in the Magnetic 
Resonance (MR) Environment
Guidance for Industry and 
Food and Drug Administration Staff 
This guidance represents the current thinking of the Food and Drug Administration (FDA 
or Agency) on this topic. It does not establish any rights for any person and is not binding 
on FDA or the public. You can use an alternative approach if it satisfies the requirements 
of the applicable statutes and regulations. To discuss an alternative approach, contact the 
FDA staff or Office responsible for this guidance as listed on the title page. 
Introduction 
This guidance document provides Food and Drug Administrations (FDAs or the Agencys) 
recommendations on testing to assess the safety and compatibility of medical devices in the 
Magnetic Resonance (MR) Environment and the recommended format for Magnetic 
Resonance Imaging (MRI) Safety Information in medical device labeling. This guidance 
supersedes FDAs Guidance entitled Establishing Safety and Compatibility of Passive 
Implants in the Magnetic Resonance (MR) Environment, dated December 11, 2014. 
Throughout this guidance, the terms FDA, the Agency, we, and us refer to the Food 
and Drug Administration and the terms you and yours refer to medical device 
manufacturers.
For the current edition of the FDA-recognized standard(s) referenced in this document, see 
the FDA Recognized Consensus Standards Database.1 If submitting a Declaration of 
Conformity to a recognized standard, we recommend you include the appropriate supporting 
documentation. For more information regarding use of consensus standards in regulatory 
submissions, please refer to the FDA guidance titled Appropriate Use of Voluntary 
Consensus Standards in Premarket Submissions for Medical Devices.2
1https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/search.cfm
2https://www.fda.gov/regulatory-information/search-fda-guidance-documents/appropriate-use-voluntary-consensus-
standards-premarket-submissions-medical-devices
1 Contains Nonbinding Recommendations
In general, FDAs guidance documents do not establish legally enforceable responsibilities. 
Instead, guidances describe the Agencys current thinking on a topic and should be viewed 
only as recommendations, unless specific regulatory or statutory requirements are cited. The 
use of the word should in Agency guidances means that something is suggested or 
recommended, but not required.
Scope 
This guidance document applies to all medical devices that might be used in the MR 
environment.  This includes all implanted medical devices, medical devices that are fastened 
to or carried by a patient (e.g., external insulin pump, pulse oximeter), medical devices that 
would reasonably be anticipated to enter the MR environment during clinical care, and all 
medical devices that are intended to enter the MR environment. The recommendations in this 
guidance for MR labeling of devices are consistent with ASTM F2503 Standard Practice for 
Marking Medical Devices and Other Items for Safety in the Magnetic Resonance 
Environment.
This guidance document does not apply to the MR system or associated components such as 
accessory spacing pads and coils.
This guidance document provides recommendations on MRI safety and compatibility 
assessments and labeling information that should be included in premarket submissions (i.e., 
premarket approval (PMA) applications, humanitarian device exemption (HDE) applications, 
premarket notification (510(k)) submissions, investigational device exemption (IDE) 
applications, and De Novo requests).
Terminology 
We recommend using the following terminology when testing your medical device for safety 
in the MR environment and labeling your medical device with one of the three standardized 
terms: MR Safe, MR Unsafe and MR Conditional.
Active medical devicemedical device relying for its functioning on a source of electrical 
energy or any source of power other than that directly generated by the human body or 
gravity3
Active implantable medical device (AIMD) active medical device which is intended to 
be totally or partially introduced, surgically or medically, into the human body or by medical 
intervention into a natural orifice, and which is intended to remain after the procedure4
3ISO 14708-1:2014 Active implantable medical devices -- Part 1: General requirements for safety, marking and for 
information to be provided by the manufacturer
4ISO 14708-1:2014 Active implantable medical devices -- Part 1: General requirements for safety, marking and for 
information to be provided by the manufacturer
2 Contains Nonbinding Recommendations
Controlled Access Areaarea around the MR system, to which access is controlled to 
prevent harm from the Static magnetic field5
Magnetic Resonance (MR) environment three dimensional volume surrounding the 
MR magnet that contains both the Special Environment (Faraday shielded volume) and the 
B  Hazard Area (space around the MR equipment where the static magnetic field can cause 
0
harm). This volume is the region in which a medical device might pose a hazard from 
exposure to the electromagnetic fields produced by the MR equipment and accessories, and 
for which access control is part of the risk mitigation.6
Magnetic Resonance (MR) Systemensemble of MR equipment, accessories including 
means for display, control, energy supplies, and the controlled access area, where provided7
MR Conditionala medical device with demonstrated safety in the MR environment 
within defined conditions including conditions for the static magnetic field, the time-varying 
gradient magnetic fields, and the radiofrequency fields8
MR Safea medical device that poses no known hazards resulting from exposure to any 
MR environment. MR Safe medical devices are composed of materials that are electrically 
nonconductive, nonmetallic, and nonmagnetic9
MR Unsafea medical device which poses unacceptable risks to the patient, medical staff 
or other persons within the MR environment10
Passive implantan implant that serves all of its function without supply of electrical 
energy or any source of power other than that directly generated by the human body or 
gravity11
Passive medical device a medical device that serves its function without supply of 
electrical energy or any source of power other than that directly generated by the human 
body or gravity
5IEC 60601-2-33:2010+AMD1:2013+AMD2:2015 CSV Medical electrical equipment -- Part 2-33: Particular 
requirements for the basic safety and essential performance of magnetic resonance equipment for medical diagnosis
6Adapted from ASTM F2503-23 Standard Practice for Marking Medical Devices and other Items for Safety in the 
Magnetic Resonance Environment, which defines the volume as a region in which an item might pose a hazard.
7IEC 60601-2-33:2010+AMD1:2013+AMD2:2015 CSV Medical electrical equipment ---- Part 2-33: Particular 
requirements for the basic safety and essential performance of magnetic resonance equipment for medical diagnosis
8Adapted from ASTM F2503-20 Standard Practice for Marking Medical Devices and other Items for Safety in the 
Magnetic Resonance Environment which defines an item with demonstrated safety.
9Adapted from ASTM F2503-20 Standard Practice for Marking Medical Devices and other Items for Safety in the 
Magnetic Resonance Environment which defines an item that poses no known hazards and MR Safe items...
10Adapted from ASTM F2503-20 Standard Practice for Marking Medical Devices and other Items for Safety in the 
Magnetic Resonance Environment which defines an item which poses unacceptable risks.
11Adapted from ASTM F2182-19e2 Standard Test Method for Measurement of Measurement of Radio Frequency Induced 
Heating Near Passive Implants During Magnetic Resonance Imaging which defines an implant that serves all of its 
function without supply of electrical power.
3 Contains Nonbinding Recommendations
Relevant Consensus Standards and Guidance 
Documents 
The following FDA-recognized consensus standards and guidance documents may be useful 
when assessing the safety of a medical device within the MR environment or developing 
MRI Safety Information for the medical device labeling. The listed documents are general or 
cross-cutting consensus standards or guidances that apply broadly to many medical devices. 
Consensus standards or guidance documents for specific medical devices may also include 
device-specific recommendations for MRI safety testing and labeling.12
Consensus Standards 
For the current edition of the FDA-recognized consensus standards referenced in this 
document, see the FDA Recognized Consensus Standards Database.13
1. ASTM F2052 Standard Test Method for Measurement of Magnetically Induced 
Displacement Force on Medical Devices in the Magnetic Resonance Environment.
2. ASTM F2119 Standard Test Method for Evaluation of MR Image Artifacts from Passive 
Implants.
3. ASTM F2182 Standard Test Method for Measurement of Radio Frequency Induced 
Heating on or Near Passive Implants During Magnetic Resonance Imaging.
4. ASTM F2213 Standard Test Method for Measurement of Magnetically Induced Torque 
on Medical Devices in the Magnetic Resonance Environment.
5. ASTM F2503 Standard Practice for Marking Medical Devices and Other Items for 
Safety in the Magnetic Resonance Environment.
6. ISO (International Organization for Standardization)/TS (Technical Specification) 10974 
Assessment of the safety of magnetic resonance imaging for patients with an active 
implantable medical device.
NOTE: As of the date of the issuance of this guidance, ISO/TS 10974 contained 
extensive information addressing assessment of the safety of active implantable medical 
devices (AIMDs) into the MR environment. While the scope of ISO/TS 10974 is AIMDs, 
it contains detailed information about hazards for medical devices in the MR environment 
and methods for assessing specific hazards that can be useful for other types of medical 
devices.
7. IEC 60601-2-33 Medical electrical equipment -- Part 2-33: Particular requirements for 
the basic safety and essential performance of magnetic resonance equipment for medical 
diagnosis. 
12See: https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/guidance-
documents-medical-devices-and-radiation-emitting-products
13Available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/search.cfm
4 Contains Nonbinding Recommendations
Guidance Documents 
1. The Assessment of Radiofrequency-Induced Heating in the Magnetic Resonance (MR) 
Environment for Multi-Configuration Passive Medical Devices guidance issued March 22, 
201614
2. Reporting of Computational Modeling Studies in Medical Device Submissions 
guidance issued on September 21, 201615
3. Requests for Feedback and Meetings for Medical Device Submissions: The Q- 
Submission Program guidance issued May 7, 201916
4. Recommended Content and Format of Complete Test Reports for Non-Clinical Bench 
Performance Testing in Premarket Submissions guidance issued on April 26, 201917
5. Submission of Premarket Notifications for Magnetic Resonance Diagnostic Devices 
guidance issued on November 18, 201618
Addressing Hazards for Medical Devices in the MR 
Environment 
The MR environment presents unique safety hazards for patients and other persons with 
medical devices near or inside an MR system bore.19 Ensuring safety and effectiveness for 
implants and other medical devices anticipated to enter the MR environment should be an 
integral part of medical device risk management. Appropriate testing and analyses,scientific 
 
rationale, and labeling, such as well supported MR Conditional labeling as described below, 
form the basis of adequate mitigations for the unique safety hazards of the MR environment.
The hazards caused by the presence of a medical device in the MR environment are listed 
and described below. Standardized test methods that address specific hazards are listed in the 
relevant section below. When available, standardized test methods to address specific 
hazards should be used. Note that the worst-case medical device size or configuration may 
vary for different hazards as described in the individual sections below.
The characteristics of the static magnetic field, gradient magnetic fields and radiofrequency 
coils may vary significantly in different MR systems and thus can lead to different risk 
profiles for a device. The safety and conditions of use of a medical device should be assessed 
or an adequate scientific rationale provided, for each magnetic field strength (e.g., 0.25 T, 1.2 
T, 1.5 T, 3.0 T, 7.0 T) MR system, radiofrequency (RF) transmit coil type (e.g., whole-body 
14https://www.fda.gov/regulatory-information/search-fda-guidance-documents/assessment-radiofrequency-induced-heating-
magnetic-resonance-mr-environment-multi-configuration
15https://www.fda.gov/regulatory-information/search-fda-guidance-documents/reporting-computational-modeling-studies-
medical-device-submissions
16https://www.fda.gov/regulatory-information/search-fda-guidance-documents/requests-feedback-and-meetings-medical-
device-submissions-q-submission-program
17https://www.fda.gov/regulatory-information/search-fda-guidance-documents/recommended-content-and-format-non-
clinical-bench-performance-testing-information-premarket
18https://www.fda.gov/regulatory-information/search-fda-guidance-documents/submission-premarket-notifications-
magnetic-resonance-diagnostic-devices
19Woods, T.O. MRI Safety in Wiley Encyclopedia of Biomedical Engineering (Metin Akay, ed.) Hoboken: John Wiley & 
Sons, Inc., 2006, pp. 2360-2371.
5 Contains Nonbinding Recommendations
transmit coil, head RF transmit-receive coil) and RF excitation (e.g., Circularly Polarized 
(CP), Multichannel-2 (MC-2)) to which the medical device is anticipated to be exposed. 
Testing may not be warranted if an adequate scientific rationale or validated computational 
modeling/simulation is provided.
A medical device that is MR Conditional in a 1.5 T MR system may be unsafe in higher or 
lower field MR systems. For instance, depending on the size and shape of the device, device 
heating may be greater or less in MR systems with higher or lower magnetic field strength. In 
addition, for a specific type of device, conditions for safe use may not be the same for all 
models.  
For electrically active medical devices that are intended to function during the MR procedure 
or in the MR environment (for example, an electrically active medical device that is intended 
to monitor the patient or deliver therapy) appropriate testing, adequate scientific rationale, 
and/or validated computational modeling/simulation should demonstrate safe use and 
intended performance during the MR procedure. This is important due to presence of higher 
Electromagnetic Interference (EMI) risks both due to strong emissions from the MR system 
as well as the sensitivity of MR systems to RF noise from active devices. 
For devices belonging to the same device type, the risk produced by the individual hazards 
can vary due to differences in the design of the individual device model.  If you have 
questions about the most appropriate testing for your specific medical device, we encourage 
you to seek input from FDA as you develop the specific test plan for your medical device. 
See the FDA guidance Requests for Feedback and Meetings for Medical Device 
Submissions: The Q-Submission Program20 for more information on constructing your pre-
submission.
Magnetically Induced Displacement Force
 
The spatial gradient of the static magnetic field (spatial field gradient) induces a 
displacement force on magnetic materials. This force is greatest near the entrance to the MR 
system bore. Magnetically induced displacement force may cause tissue damage by inducing 
unwanted movement or dislodgement of the medical device. In addition, typical designs and 
shapes of large equipment (e.g., patient monitors, injectors) can be vulnerable to tipping over 
when subjected to magnetically induced forces and/or torques. 
 
This hazard should be addressed for all medical devices anticipated to enter the MR 
environment. For relatively small medical devices that can be suspended from a string, 
ASTM F2052 provides a test method for the measurement of magnetically induced 
displacement force. For medical devices that are too large to suspend from a string, we 
recommend you develop alternate test methods to assess the magnetically induced 
displacement force and appropriate conditions for safe use. For medical devices composed of 
paramagnetic materials whose magnetic properties are not affected by processing and 
fabrication, it may be possible to leverage test results and analyses for devices or material 
20https://www.fda.gov/regulatory-information/search-fda-guidance-documents/requests-feedback-and-meetings-medical-
device-submissions-q-submission-program
6 Contains Nonbinding Recommendations
samples composed of the same material as the subject medical device.21 Magnetically 
induced force and torque testing on devices composed of alloys whose magnetic properties 
may be altered during processing and fabrication (e.g., nitinol and austenitic stainless steels 
like grades 303 and 304 stainless steel) should be performed on a finished device and should 
not be leveraged from other device or material testing.
For large equipment that can be mounted to a cart or stand and might contain wheels, you 
should also assess the propensity of the medical device to tip or topple due to magnetically 
induced displacement forces and torques.
For medical devices that come in multiple sizes, the medical device with the greatest mass of 
magnetic material, or with the largest proportion of magnetic material to total mass, is 
typically the worst-case for the assessment of magnetically induced displacement force.
To mitigate the possibility of a projectile event for medical devices anticipated to be used 
inside the MRI scanner room but outside the MR system bore (e.g., ventilators and anesthesia 
systems), we recommend that the medical device be permanently secured so that it cannot be 
moved into a hazardous area. If this is not possible, we recommend that you include one or 
more of the following as part of your medical device: dead-man brakes, gauss meters 
mounted on the medical device, and/or nonferromagnetic tethers. Dead-man brakes and 
tethers reduce the potential for freely-moving projectiles. A gauss meter mounted on the 
medical device will not stop an object from being a projectile. However, a gauss meter 
mounted on the medical device that generates an audible or visual alarm may be helpful in 
alerting the user when a given static magnetic field is detected.
A maximum magnetically induced displacement force of less than or equal to the 
gravitational force on the medical device is often used as a conservative acceptance criterion 
for implants. A greater magnetically induced displacement force may be acceptable for 
implants or medical devices that are fastened to a patient depending on the properties of the 
tissue adjacent to the implant or medical device and the means by which an external medical 
device is fastened to the patient. Similarly, an acceptance criterion greater than the 
gravitational force could be used for a medical device that is not attached to a patient if a 
system is provided to prevent the device from entering the region in which it would become a 
projectile. Such systems might include permanent mounting to the MR system room, 
nonferromagnetic tethers, dead-man brakes and/or magnetic field alarms. 
Magnetically Induced Torque 
The MR systems static magnetic field induces a torque on magnetic materials. This 
magnetically induced torque may cause tissue damage by inducing unwanted movement or 
dislodgement of the medical device. The magnetically induced torque is proportional to the 
static magnetic field strength and is the greatest inside the MR system bore where the static 
magnetic field strength is greatest. 
21T. Woods, J. Delfino, and S. Rajan, "Assessment of Magnetically Induced Displacement Force and Torque on Metal 
Alloys Used in Medical Devices," Journal of Testing and Evaluation Volume 49, issue 2 (March 2021) (published online 
2019). https://doi.org/10.1520/JTE20190096.
7 Contains Nonbinding Recommendations
This hazard should be addressed for all medical devices anticipated to enter the MR system. 
ASTM F2213 provides standard methods for measuring magnetically induced torque for 
medical devices in the region of the uniform magnetic field in an MR system. Some 
experimentation may be needed to determine the worst-case device size and configuration for 
assessing magnetically induced torque. 
A maximum magnetically induced torque of less than or equal to the gravitational torque on 
the medical device is often used as a conservative acceptance criterion. A greater 
magnetically induced torque may be acceptable depending on the type of tissue adjacent to 
the medical device or how an external medical device is fastened to the patient or restrained 
from moving when it is within the MR environment.
Heating  
The radiofrequency (RF) and time-varying gradient fields (dB/dt) of the MR system can 
induce heating of the tissue adjacent to the medical device and/or heating of the medical 
device itself. This hazard should be addressed for all medical devices anticipated to enter the 
bore of the MR system.
RF induced heating
RF induced tissue heating is a complex interaction that depends on many variables, including 
the characteristics of the transmit RF coil of the MR system (e.g., geometry, tuning, source 
location), frequency, the RF transmit mode (e.g., Circularly Polarized (CP), Multichannel-2 
(MC-2)), as well as patient anatomy, tissue properties, and position with respect to the RF 
coil (i.e., imaging landmark). In addition, for patients with implanted or patient-contacting 
medical devices, the RF induced heating also depends on the medical device characteristics 
(e.g., geometry, size, materials, physical properties, configuration) and location within the RF 
field and within or on the patient. The RF safety evaluation of medical devices anticipated to 
be used within the MR environment should take into consideration all these variables to 
ensure that a clinically relevant worst-case heating scenario is assessed. In some cases, when 
a large number of variables are present (for example for multiple lead paths for a device with 
a lead), a risk-based assessment to determine a percentile for the heating comparison rather 
than a worst-case approach could be used. Such evaluation can include appropriate 
experimental measurements, computational modeling and simulations (e.g., virtual 
anatomical models), data from scientific literature, and/or a scientific rationale.
In this context, medical devices are typically categorized as
 fully implanted passive medical devices (e.g., stents, clips, screws, plates, heart 
valves, hip implants),
 AIMDs (e.g., neurostimulators, pacemakers, cochlear implants), 
 partially implanted medical devices (e.g., MR-guided ablation catheters, orthopedic 
external fixators), or 
 medical devices that are external and connected to the body (e.g., EEG electrodes, 
ECG electrodes, pulse oximeters, head frames).
8 Contains Nonbinding Recommendations
For fully implanted passive medical devices, ASTM F2182 provides a method for 
measurement of RF induced heating. The FDA Guidance Document on the Assessment of 
Radiofrequency Induced Heating in the Magnetic Resonance (MR) Environment for Multi-
Configuration Passive Medical Devices22 provides information that may assist in 
determining worst-case configurations used to assess RF induced heating for multi-
configuration passive medical devices. Note that this guidance can also be used to determine 
the location of the greatest expected temperature rise for passive medical devices with a 
single configuration (e.g., stents). The RF induced heating assessment should consider the 
possibility that during Normal Operating Mode as defined in IEC 60601-2-33, the whole-
body Specific Absorption Rate (SAR) can exceed 2 W/kg for short intervals.
When the implant is located inside the local RF transmit coil, RF induced heating should be 
determined by local exposure (local SAR, B )rather than the whole-body SAR. A 
1+rms  
scientific rationale could be used to determine safe scan conditions for an implant located 
outside the local RF transmit coil.
A passive implant with dimensions of less than 2 cm in all directions and at least 3 cm away 
from another passive implant does not need to be tested with respect to RF induced heating at 
3.0 T or less, as it is expected to generate a temperature increase of less than 2 C in Normal 
Operating Mode, over the course of 1 hour of exposure. This test exclusion is not valid (i) 
when multiple replicas of the implant (e.g., multiple metallic anchors) are implanted within 3 
cm of each other, or (ii) part of the implant is outside the patient. The 3 cm distance is 
recommended to avoid any RF coupling with neighboring implants.23,24,25 For devices where 
multiple replicas can be joined, the worst-case condition should be assessed. 
If a sound scientific rationale is provided, it may be possible to leverage RF induced heating 
testing and analyses for one passive implant to another passive implant with similar geometry 
and electrical properties.
For AIMDs, ISO/TS 10974 provides a tiered approach for assessing RF induced heating.
There are no standard methods for assessing RF induced heating in the MR environment for 
partially implanted medical devices or medical devices that are external and patient-
contacting. These devices include shielding materials, high permittivity blocks or dielectric 
pads that should be evaluated for RF safety because of the significant effects of these devices 
on the electric fields present around them. ASTM F2182 was developed for fully implanted 
medical devices and the phantom test described is not appropriate for partially implanted 
medical devices or medical devices that are external and patient-contacting. Therefore, we 
22https://www.fda.gov/regulatory-information/search-fda-guidance-documents/assessment-radiofrequency-induced-heating-
magnetic-resonance-mr-environment-multi-configuration
23Song T, Xu Z, Iacono MI, Angelone LM, Rajan SS, Retrospective Analysis of RF Heating measurements of Passive 
Medical Implants, Magn Reson Med., 2018, pp. 27262730. http://dx.doi.org/10.1002/mrm.27346.
24Yeung CJ, Susil RC, Atalar E, RF Safety of Wires in Interventional MRI: Using a Safety Index, Magn Reson Med, 
2002, pp. 187193.
25ISO 14708-3-2017 Implants for surgery - Active implantable medical devices  Part 3: Implantable neurostimulators
9 Contains Nonbinding Recommendations
recommend you seek feedback through the Q-submission process on the proposed test plan 
for assessing heating and the corresponding MRI safety labeling for these devices.
Acceptance criteria for the temperature/time dose should be established based on the location 
of the medical device in or on the body using a scientific rationale or existing literature. No 
rationale is needed for a temperature increase up to 2 C for the SAR condition in the 
labeling.26
A patient, with a device that was demonstrated to heat adjacent thermally sensitive tissue 
(e.g., brain, eyes, neural tissue, testes, and ovaries) up to 2 C in 15 minutes in Normal 
Operating Mode can be scanned for 1 hour in Normal Operating Mode without a cooling 
period.27,28For devices that heat thermally sensitive tissues more than 2 C in 15 minutes, the 
manufacturer should determine a scan time with an appropriate cooling period. 
A patient with a device that was demonstrated to heat adjacent tissue that is not thermally 
sensitive up to 4 C in 15 minutes in Normal Operating Mode can be scanned for 1 hour in 
Normal Operating Mode without a cooling period.29,30For devices that heat adjacent tissue 
that is not thermally sensitive by more than 4 C, in 15 minutes, in Normal Operating Mode, 
the manufacturer should determine a scan time with an appropriate cooling period.
Heating induced by time-varying magnetic field gradients, (dB/dt)
Exposure to time-varying magnetic fields (gradient pulses) can induce eddy currents on 
conductive surfaces of conductive/metallic implants, and in the internal conductive 
components of AIMDs placed inside the bore of the MR system.31 The power deposited by 
the magnetic field gradients is primarily determined by the surface area and thickness of the 
conductor, rate of change of the magnetic field, electrical conductivity, and the relative 
orientation of the conductive loops to the varying magnetic fields. The power deposited is 
also determined by the location in the bore, since the strength of the time-varying magnetic 
field changes with time and location.
ISO/TS 10974 includes test methods for the assessment of gradient induced heating for 
AIMDs. There are no standard test methods for the assessment of gradient induced heating 
for passive medical devices. Due to the typical small planar surface area, gradient induced 
heating is generally not expected to pose a hazard for tissue damage or medical device 
malfunction for passive medical devices. However, it can be significant in some large passive 
26ISO 14708-3-2017 Implants for surgery - Active implantable medical devices  Part 3: Implantable neurostimulators
27Shrivastava D, Utecht L, Tian J, Hughes J, and Vaughan JT, In Vivo Radiofrequency Heating in Swine in a 3T (123.2 
MHz) Birdcage Whole-Body Coil, Magn Reson Med., 2014, Vol. 72, No. 4, pp. 1141-50. 
(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4041852/)
28Tian J, Shrivastava, D, In Vivo Radiofrequency Heating in a 3T MRI Scanner, 2018, in Theory and Applications of 
Heat Transfer in Humans, Editor Shrivastava D, John Wiley and Sons, Chichester, West Sussex, UK.
29Shrivastava D, Utecht L, Tian J, Hughes J, and Vaughan JT, In Vivo Radiofrequency Heating in Swine in a 3T (123.2 
MHz) Birdcage Whole-Body Coil, Magn Reson Med., 2014, Vol. 72, No. 4, pp. 1141-50. 
(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4041852/)
30Tian J, Shrivastava, D, In Vivo Radiofrequency Heating in a 3T MRI Scanner, 2018, in Theory and Applications of 
Heat Transfer in Humans, Editor Shrivastava D, John Wiley and Sons, Chichester, West Sussex, UK.
31Winter L, Seifert F, Zilberti L, Murbach M, Ittermann B. MRIRelated Heating of Implants and Devices: A Review. 
Journal of Magnetic Resonance Imaging. 2020 May 26.
10 Contains Nonbinding Recommendations
implants such as cranial plates. The ISO/TS 10974 methods using dB/dt (rms and peak) can 
be adapted to test passive medical devices. Testing for passive medical devices may not be 
warranted if a sound scientific rationale is provided. In determining whether testing for 
gradient induced heating of a passive medical device is warranted, the following factors may 
be useful to consider. All the following conditions need to be present for gradient induced 
heating of a metal implant to reach a clinically significant level: 1) large and symmetric 
surface area of the medical device, 2) dB/dt perpendicular to the large surface of the medical 
device, 3) large sustained gradient slew rate, and 4) the medical device is located in the 
region of the MR system bore where dB/dt is most intense.32
Due to the rapid drop-off of the gradient fields outside the MR system bore, gradient induced 
heating does not pose a thermal hazard for medical devices located outside the bore.
Acceptance criteria for temperature/time dose should be established based on the location of 
the medical device in or on the body using scientific rationale or existing literature. No 
rationale is needed for a local tissue temperature increase of up to 2 C at the labeled SAR 
condition.33
Gradient Induced Vibration  
The MR systems pulsed gradient magnetic fields, dB/dt, may induce forces on metallic 
medical devices that result in vibration of the device. This gradient induced vibration may 
lead to device malfunction or tissue damage. This hazard should be addressed for all AIMDs. 
Testing may not be warranted if a sound scientific rationale is provided. ISO/TS 10974 
provides a test method for the assessment of gradient induced vibration for AIMDs. Due to 
the typical small planar surface area, gradient induced vibration is generally not expected to 
pose a hazard for tissue damage or medical device malfunction for passive medical devices. 
In determining whether testing for gradient induced vibration of a passive implant is 
warranted, the following information may be useful to consider. All the following conditions 
need to be present for gradient induced vibration of a metal implant to reach a clinically 
significant level: 1) large and symmetric surface area of the medical device, 2) dB/dt 
perpendicular to the large surface of the implant, 3) large sustained gradient slew rate, and 4) 
implant is located in the region of the MR system bore where dB/dt is most intense.34 
 
Acceptance criteria for gradient induced vibration should be established based on the location 
of the medical device in or on the body and the location inside the magnet using a scientific 
rationale or existing literature. The acceptance criteria should address the potential for tissue 
damage and device malfunction for specific functions of the medical device.
32Nyenhuis JA, Heating and torque of passive metallic implants by gradient dBdt and static field B0 in MRI, ISMRM 
2020 Annual Meeting and Exhibition, Paris, France, August 8-20, 2020.
33ISO_14708-3-2017 Implants for surgery - Active implantable medical devices  Part 3: Implantable neurostimulators
34Nyenhuis JA, Heating and torque of passive metallic implants by gradient dBdt and static field B0 in MRI, ISMRM 
2020 Annual Meeting and Exhibition, Paris, France, August 8-20, 2020.
11 Contains Nonbinding Recommendations
Gradient Induced Extrinsic Electrical Potential 
(Unintended Stimulation) 
The time-varying gradient magnetic fields associated with an MR exam can induce an 
electric potential at the electrodes of a lead. Extrinsic electric potential may develop within a 
single AIMD lead (intra-lead), between electrodes of a multi-lead AIMD (inter-lead), or 
between electrodes and a conductive AIMD enclosure in contact with tissue. The induced 
voltage can generate currents that can cause unintended physiologic stimulation or medical 
device malfunction. This hazard should be addressed for AIMDs and partially implanted 
active medical devices that contain electrodes or leads that contact neural or muscular tissue. 
 
The tests outlined in ISO/TS 10974 measure the amount of unintended charge and the current 
flow due to time-varying gradient magnetic fields.
Acceptance criteria should be established based on the location of the medical device in or on 
the body and the location in the MR system bore using a scientific rationale or existing 
literature.
Rectification of RF pulses from MR Exams 
(Unintended Stimulation) 
In the context of active medical devices in the MR environment, rectification refers to the 
conversion of RF waveforms to slowly varying voltages that are capable of unintended tissue 
stimulation. Unintended tissue stimulation can occur if the rectified voltages are generated at 
the active medical device electrodes.
This hazard should be addressed for AIMDs, for partially implanted active medical devices 
and for non-implanted active medical devices that contain electrodes that contact neural or 
muscular tissue. The tests outlined in ISO/TS 10974 measure the levels of rectified voltages 
generated by the AIMD during RF exposure. These methods may be adapted for partially 
implanted and non-implanted active medical devices that contain electrodes that contact 
neural or muscular tissue. 
Acceptance criteria should be established based on the location of the medical device in or on 
the body and the location in the MR system using a scientific rationale or existing literature.
Medical Device Malfunction 
The exposure to the MR environment of active medical devices (e.g., AIMDs, partially 
implanted active devices, patient monitors, infusion pumps, active accessories, RF tuned 
components, and magnetizing components) and passive medical devices with magnetic or 
magnetically controlled components (e.g., magnetic switches and inductive loops) or 
thermally controlled components may cause the medical device to malfunction. Medical 
device malfunction due to exposure to the MR systems electric and magnetic fields should 
be addressed for these types of devices. Such malfunctions can be either temporary during 
the MR exposure or procedure, or permanent and continue after the exposure.  
 
12 Contains Nonbinding Recommendations
For AIMDs or devices with electrical circuits, we recommend that you demonstrate that the 
static magnetic fields (B ), time-varying gradient magnetic fields (dB/dt), and pulsed 
0
radiofrequency (RF) fields of the MR system do not affect the performance or safe operation 
of the medical device.
ISO/TS 10974 provides standardized test methods for assessing AIMD malfunction in the 
MR environment. These include potential malfunctions induced by MR fields, including:
 Static magnetic field (B )
0
 RF fields
 Time-varying gradient magnetic fields (dB/dt)
 Combined fields
The test methods outlined in ISO/TS 10974 involve measurements and testing in both 
simulated and actual MR systems. They also include testing for each type of field separately. 
Because the field exposure during MR exams involves concurrent exposure of static 
magnetic field, RF and pulsed gradient fields, the medical device should also be tested by 
exposing the medical device to typical MR pulse sequences in an MR system using the 
ISO/TS 10974 test methods for combined fields. These methods rely on testing a medical 
device before the scan and monitoring the medical device during the scan, if applicable, to 
verify each intended function. The device should be assessed for proper operation as per 
intended use within 30 minutes of the exposure and should be tested comprehensively for 
damage and malfunction with 14 days of the exposure. This method simulates MR exams in 
a clinical setting and helps to demonstrate medical device safety and function through 
performance function tests. The timeline for the combined fields testing is important because 
malfunction or EMI to the medical device can be permanent or temporary.
For non-implanted active medical devices or medical devices anticipated to be actively used 
during the MR exposure, you should demonstrate that the MR system does not affect or 
degrade the operation of the medical device in its intended use location. For example, for a 
patient monitor anticipated to remain outside the 20 mT (200 gauss) field line, you should 
demonstrate that the patient monitor continues to meet its performance specifications while 
in its location within the MR environment.
Medical device malfunction due to exposure to the MR system electric and magnetic fields is 
not generally expected for passive medical devices, although there can be exceptions for 
which medical device malfunction in the MR environment should be assessed, such as for 
implanted passive drug infusion pumps that are activated by body temperature, medical 
devices with inductive loops, oxygen tank regulators containing ferromagnetic springs, or 
magnetically activated or operated switches. For these types of passive medical devices, we 
recommend you demonstrate that exposure to the static magnetic fields (B ), time-varying 
0
magnetic fields (dB/dt), and/or RF fields, as appropriate, do not adversely affect the 
performance or safe operation of the medical device.
Acceptance criteria should be based on safety and the essential performance of the medical 
device.
13 Contains Nonbinding Recommendations
In addition to electrical and magnetic fields, acoustic noise should also be considered if the 
device or accessory is susceptible to interference from the acoustic exposure of the MR 
system (e.g., a servo ventilator with a pressure sensor that may receive a signal generated as 
acoustic noise by the MR system).
In addition to malfunction of the medical device, you should assess and demonstrate that the 
medical device does not affect the operation of the MR system.
Extent of Image Artifact 
The presence of metallic implants or other medical devices can lead to artifacts in the acquired 
MR images. The operation of an active medical device may lead to artifacts or corruption of 
the acquired MR images. Both can lead to uninterpretable or non-diagnostic images or disease-
mimicking artifacts. This issue should be addressed for all medical devices anticipated to enter 
the MR environment by including a statement in the MR Conditional labeling to inform health 
care providers about the potential for medical device induced image artifacts.
ASTM F2119 provides a standardized test method for the assessment of susceptibility image 
artifact. While the scope of this standard is passive implanted medical devices, the method 
can also be applied to AIMDs, partially implanted medical devices, or non-implanted 
medical devices that are anticipated to be in the MR system bore.
For medical devices that come in multiple sizes, the largest medical device or the medical 
device with the largest amount of magnetic material can generally serve as a worst-case for 
assessing magnetic susceptibility image artifact. For multi-component medical devices, all 
clinically relevant configurations should be considered to determine which one(s) adequately 
represent the worst-case(s) for assessing image artifact, a scientific rationale provided, and 
assessment and/or testing performed accordingly.
For electrically active medical devices that do not enter the MR system bore, 
Electromagnetic Compatibility (EMC) emissions should meet criteria defined for the special 
environment35 as specified by the MR system manufacturer.36 While no standardized test 
methods currently exist to assess image artifact produced by electrically active medical 
devices that do not enter the MR system bore, a qualitative assessment of image quality and a 
measurement of signal to noise ratio (SNR) using standardized test methods (such as NEMA 
MS 137) with and without the medical device present may be useful.
In general, there are no acceptance criteria for image artifact, as the intent of including image 
artifact information in the medical device labeling is to provide health care providers 
information they can use in making the benefit-risk decision about the MR exam for the 
35IEC 60601-1-2 Medical electrical equipment -Part 1-2: General Requirements for Basic Safety and Essential 
Performance - Collateral standard: Electromagnetic Disturbances-Requirements and Tests
36Submission of Premarket Notifications for Magnetic Resonance Diagnostic Devices guidance issued on November 18, 
2016, available at https://www.fda.gov/regulatory-information/search-fda-guidance-documents/submission-premarket-
notifications-magnetic-resonance-diagnostic-devices
37NEMA MS 1-2008 (R2014) Determination of Signal-to-Noise Ratio (SNR) in Diagnostic Magnetic Resonance Imaging
14 Contains Nonbinding Recommendations
patient. Additional information regarding image artifact may be needed for implanted 
medical devices (e.g., cochlear implants) for which follow-up MR exam is routinely 
performed. If you wish to indicate in your medical device labeling that diagnostic MRI is 
possible within a specified distance of an implanted medical device (e.g., MR angiography to 
demonstrate vessel patency after aneurysm coil placement), this claim should be supported in 
your premarket submission.
Reporting Results 
We recommend you provide test report summaries, and if applicable, complete test reports, 
as described in the FDA guidance titled Recommended Content and Format of Non- 
Clinical Bench Performance Testing Information in Premarket Submissions.38 In addition, 
you should provide the following information in the test report summaries and complete test 
reports:
 List the hazard addressed by the test.
 List the test equipment used. When testing is performed using an MR system, please 
specify the system field strength, manufacturer, model, and software version. If 
appropriate, also list MRI sequences used in the test.
 When using a consensus standard in which the content of a test report is defined, results 
should be reported as defined in the consensus standard. If computational modeling is 
used, the report should follow the FDA Guidance Reporting of Computational Modeling 
Studies in Medical Device Submissions.39
 For testing based on ASTM F2182, the RF induced heating results should be expressed in 
C/(V/m) or in C/(W/kg), where V/m and W/kg refer to the local background levels in 
the ASTM phantom in the absence of the tested device.
 When ASTM F2182 is used, the values for C/(V/m) or in C/(W/kg) should be scaled to 
a temperature increase (in C) for the exposure conditions specified in the MR 
Conditional labeling. The scaling of results from ASTM F2182 to create MR Conditional 
labeling can be performed using computational modeling or a scientific rationale.
 As an alternative to a written narrative for each non-clinical bench performance test, a 
tabulated summary can be provided to organize the information recommended in a test 
report summary (see Table 1 below for an example of the format). If a summary table is 
used, it is still recommended that a narrative discussion of the results/conclusions be 
provided as described in Section II.A.6 of the FDA guidance titled Recommended 
Content and Format of Non-Clinical Bench Performance Testing Information in 
Premarket Submissions,40 when needed. An example for a passive implant is shown in 
Table 2 in Appendix 1.
38https://www.fda.gov/regulatory-information/search-fda-guidance-documents/recommended-content-and-format-non-
clinical-bench-performance-testing-information-premarket
39https://www.fda.gov/regulatory-information/search-fda-guidance-documents/reporting-computational-modeling-studies-
medical-device-submissions
40https://www.fda.gov/regulatory-information/search-fda-guidance-documents/recommended-content-and-format-non-
clinical-bench-performance-testing-information-premarket
15 Contains Nonbinding Recommendations
Medical 
Test  Acceptance  Device  Summary of Test 
Hazard  Method  Criterion and  Configuration  Results and pass/fail  Location in 
Addressed Used Rationale Tested if Appropriate Submission
Hazard 1 Method 1
Hazard 2 Method 2
Hazard n Method n
Table 1. Test result summary table including columns that should be included for each test. 
MRI Safety Labeling 
A premarket submission must include labeling in sufficient detail to satisfy any 
applicable requirements for the type of premarket submission (e.g., 21 CFR 807.87(e) or 
21 CFR 406 814.20(b)(10)). In addition, device labeling must satisfy all applicable FDA 
labeling requirements, including, but not limited to, 21 CFR part 801. Your device 
labeling should include sufficient information for a healthcare professional to determine 
whether a device can safely enter the MR environment. Specifically, we recommend that 
you include information describing the safety of your medical device in the MR 
environment in a separate section of your labeling entitled MRI Safety Information. 
To make it easier for users to locate, we recommend that this section be included in the 
table of contents of your labeling document(s), if applicable. Based on the results of your 
assessment, you should label your medical device as MR Safe, MR Unsafe, or MR 
Conditional, and include the appropriate symbol from ASTM F2503 and/or the 
corresponding term in your labeling. The color versions of the symbols are 
recommended, but the black and white versions can be used. As original labeling may 
not always be available to patients and healthcare providers for the entire life of the 
medical device, the MRI safety information should be readily accessible, for instance on 
the manufacturers website and/or by telephone, taking care to clearly and 
unambiguously identify the medical device in all labeling. The term MR Compatible, 
which appeared in a 1997 FDA draft guidance document and was frequently 
misinterpreted, is obsolete, and should not be used.
By definition, MR Safe medical devices are composed of materials that are electrically 
nonconductive, nonmetallic, and nonmagnetic.41 For the purposes of determining the safety 
of a medical device in the MR environment, a medical device can be defined as electrically 
nonconductive if the conductivity is less than 2 S/m, given that the conductivities of some 
41ASTM F2503 -20 Standard Practice for Marking Medical Devices and other Items for Safety in the Magnetic Resonance 
Environment
16 Contains Nonbinding Recommendations
human tissues reach this value. Most plastics, glass, and many ceramic materials are MR 
Safe.42 A scientific rationale (e.g., including information about the electrical conductivity and 
magnetic properties of the device material(s)) rather than testing can be used to support an 
MR Safe designation. Small metallic devices such as metal markers or polymer devices 
containing small metal radiopaque markers are not MR Safe because they contain metal and 
should be labeled MR Conditional. However, depending on the metal used, the MR 
Conditional labeling can be developed using a scientific rationale rather than testing.
Electrically active medical devices should be designated either MR Conditional or MR 
Unsafe, but not MR Safe because they contain electrically conductive components.
MRI safety labeling should include information for both patients and healthcare 
providers. As appropriate for the specific medical device, this should include 
information for the healthcare provider implanting or prescribing the medical device, the 
physician or other healthcare provider who provides continuing care for the patient with 
the medical device, and the healthcare provider who prescribes the MR exam. In 
developing this labeling information, please be aware that the healthcare provider 
prescribing the MR exam may not have implanted or provided the medical device to the 
patient or may be the healthcare provider who provides follow-up care to the patient 
with the medical device. For MR Conditional devices with conditions that restrict the 
MR system operation below Normal Operating Mode, the labeling should include 
information for the patient and healthcare providers that the MR conditions for safe use 
may limit the availability and diagnostic quality of some MR procedures.
The healthcare provider labeling should clearly and unambiguously identify the medical 
device, identify the MRI safety status of the medical device (MR Safe, MR Unsafe, or 
MR Conditional), and if the medical device is MR Conditional, provide the conditions 
for safe use in the MR environment. If the medical device is anticipated to enter the bore 
of the MR system, the conditions for safe use in the MR environment should include 
instructions for safely performing the MR procedure on a patient with the medical 
device. This might include patient preparation, procedural instructions, special medical 
device operating modes, illustrations, peripheral equipment needed, any patient or 
medical device monitoring or intervention during and after scanning, or other 
instructions to ensure safety. All intended and expected operation of the medical device 
during an MR exam should be clearly explained. Information describing the image 
artifacts caused by the presence of the device should also be provided.
The patient labeling should clearly and unambiguously identify the medical device and 
identify the MRI safety status of the medical device (MR Safe, MR Unsafe, or MR 
Conditional). For MR Unsafe implants and medical devices that are fastened to or 
carried by the patient, the patient labeling should clearly inform the patient that they 
should not receive an MR exam while the device is implanted or fastened to the patient. 
For MR Conditional medical devices, the patient information should direct the patient to 
consult with their healthcare provider prior to an MR exam and inform MRI site 
42Hess BJ, Leewood AR, Huser MS, Gopal SH, Iacono MI, Kainz W, Rajan SS, Angelone LM. Are slender devices with 
low electrical conductivity unlikely to exhibit RF-induced heating? BMES /FDA Frontiers in Medical Devices Conference 
2015.
17 Contains Nonbinding Recommendations
personnel that they have an MR Conditional medical device during MR screening prior 
to the MR exam. For MR Conditional medical devices for which patient preparation, 
peripheral equipment or specialized personnel for an MR exam is needed, this 
information should be described in the patient labeling.
To allow medical professionals to identify the specific medical devices a patient has, the 
MRI safety status of the medical devices, and the conditions for safe use in the MR 
environment for MR Conditional devices, we recommend that the patient labeling 
include a patient medical device card for implanted medical devices and for the patients 
medical devices that are fastened to or carried by the patient. The patient medical device 
card should clearly and unambiguously identify the medical device, the MRI safety 
status of the medical device (MR Safe, MR Unsafe, or MR Conditional), and, if the 
medical device is MR Conditional, either provide the conditions for safe MRI scanning 
or direct users to the location (i.e., via a URL and/or telephone number) where the MR 
Conditional labeling can be found. 
Recommendations for the content and format of labeling for MR Safe, MR Unsafe, and MR 
Conditional medical devices are given below and in the Appendices. Example labeling for 
MR Safe, MR Unsafe, and MR Conditional medical devices are also given below and in the 
Appendices.
MR Safe 
The MRI safety information for an MR Safe medical device should indicate that the medical 
device is MR Safe as defined in ASTM F2503 and as shown below. By definition, MR Safe 
medical devices do not contain any metal and are composed entirely of materials that are 
electrically nonconductive, nonmetallic, and nonmagnetic. An MR Safe medical device can 
safely be taken into any MR environment. MR Safe medical devices have no constraints or 
conditions on the MR environment or the use of the device in the MR environment. If there 
are any constraints or conditions on the MR environment or on the presence or use of the 
medical device in the MR environment, the device should not be labeled MR Safe.
For non-implanted medical devices, this information should appear directly on the medical 
device if possible. To provide MRI safety information that is concise and easy to understand, 
we recommend that labeling for MR Safe medical devices not include additional information 
that is not needed for the medical professional to safely administer an MR exam (e.g., the 
scientific rationale upon which the MR Safe determination was made). Labeling example:
MRI Safety Information
or
And/or a statement such as The <insert medical device name> is MR Safe.
18 Contains Nonbinding Recommendations
MR Unsafe 
The MRI safety information for an MR Unsafe medical device should indicate that the 
medical device is MR Unsafe and should remain outside the MRI scanner room as shown 
below. For non-implanted medical devices, the MR Unsafe icon should appear directly on 
the medical device if possible. If applicable, the labeling should also indicate that the medical 
device may be a projectile hazard. To provide MRI safety information that is concise and 
easy to understand, we recommend that labeling for MR Unsafe medical devices not include 
additional information that is not needed for the medical professional to safely administer an 
MR exam (e.g., the scientific rationale upon which the MR Unsafe determination was made). 
For example:
MRI Safety Information
And/or a statement such as The < insert medical device name > is MR Unsafe.
and, if appropriate, the statement The device presents a projectile hazard.
For non-implanted medical devices, the MR Unsafe labeling should appear directly on the 
medical device if possible. For example: 
WARNING
Projectile Hazard
For implanted medical devices and for a patients medical devices that are fastened to or 
carried by the patient (e.g., external insulin pump), we recommend that you provide a patient 
medical device card. For an MR Unsafe medical device, the patient medical device card 
should include the following information: 
 The MR Unsafe symbol and/or the term MR Unsafe, and
 A statement such as: This person <choose is implanted with or has> a 
<insert medical device name>. Do not enter an MRI scanner room or an MR 
system. Doing so may result in <choose one or more of injury or severe 
injury and/or death> and
 URL and/or phone number for the medical device manufacturer.
MR Conditional  
The labeling for MR Conditional medical devices should include the MR Conditional 
symbol,  , and/or the term MR Conditional and list the conditions under which a 
medical device that is anticipated to enter the MR environment (or a patient with an implant 
or a medical device that is fastened to or carried by the patient) can safely enter the MR 
19 Contains Nonbinding Recommendations
environment as described in ASTM F2503. The conditions of safe use should ensure safety 
but also be as concise and easy to implement as possible. Because the conditions for safe use 
may change over time (e.g., with the introduction of new field strength MR systems), 
consideration should be given to the means for providing the most current conditions for safe 
use. For MR Conditional devices with conditions that restrict the MR system operation below 
Normal Operating Mode, the labeling should include information for the patient and 
healthcare providers that the MR conditions for safe use may limit the availability and 
diagnostic quality of some MR procedures. If scanning a patient with an MR Conditional 
device could produce pain, this should be noted in the labeling. 
For an MR Conditional medical device, the patient medical device card should include at 
least the following MRI safety information:
 The MR Conditional symbol and/or the term MR Conditional, and
 A statement such as: This person <choose is implanted with or has> a 
<insert medical device name> and can safely undergo an MR exam only 
under very specific conditions. Scanning under different conditions may 
result in <choose one or more of injury or severe injury and/or 
death> or device malfunction. Full MRI safety information is available in 
the MRI Safety Information section of the <insert name of 
document/manual containing MRI safety information>, which can be 
obtained at www.<insert URL> or by calling <insert phone number>.
Patient medical device cards for specific medical device types may need additional 
information (e.g., patient name and implantation date).
Patient medical device cards for devices with relatively few conditions (e.g., many passive 
implants) can list the conditions for safe entry and use in the MR environment rather than a 
general statement such as the example above.
MR Conditional Medical Devices anticipated to enter the MR system bore
The MR Conditional labeling for a medical device anticipated to enter the MR system bore 
should include:
1. The MR Conditional symbol and/or the term MR Conditional, and
2. Nominal value(s) of permitted static magnetic field strength [T]
The following information should be included when needed for the specific medical device. 
Note that if a parameter is not listed, no modifications of that parameter are needed for the 
safe scanning of a patient with the specific medical device.
1. Nucleus being imaged by MRI. If no nucleus is listed, the nucleus is assumed to be 
1H. Additional nuclei may be included (e.g., 23Na, 31P). It is not necessary to list 1H 
only.
2. Scanner type (e.g., cylindrical-bore)
20 Contains Nonbinding Recommendations
3. Magnetic field (B ) orientation (e.g., horizontal)  
0
4. Maximum spatial field gradient [T/m] and [G/cm]
5. Maximum gradient slew rate per axis [T/m/s]
6. Radiofrequency (RF) field exposure
a. RF excitation (e.g., Circularly Polarized (CP), Multichannel-2 (MC-2)). If the 
labeled field strength includes scanners that can operate in MC-2, then RF 
excitation should be included. As of the publication of this guidance, all 1.5T 
MR systems only operate in CP RF Excitation, therefore this parameter can be 
omitted for 1.5 T MR systems.
b. RF transmit coil type (e.g., whole-body transmit coil, local RF transmit coil))
c. RF receive coil type
d. Maximum permitted whole-body averaged specific absorption rate (SAR) 
[W/kg] and/or maximum permitted head averaged SAR [W/kg]. Include 
Normal Operating Mode or First Level Controlled Operating Mode when 
applicable. 
e. Maximum B  value [mT] if applicable
1+rms
7. Scan duration and wait time (e.g., Scan for up to <insert number> minutes in a 
<insert number> minute time period. Wait <insert number> minutes before the next 
imaging session or <insert number> W/kg whole-body average SAR for <insert 
number> minutes of continuous RF (a sequence or back to back series/scan without 
breaks) followed by a wait time of <insert number> minutes if this limit is reached.)
8. MR exam exclusion zones and information on patient position relative to the MR 
system (e.g., laser-landmark positions). Include a diagram showing the exclusion 
zone(s) for imaging.
9. Information about image artifact. For example: The presence of this implant may 
produce an image artifact. Some manipulation of scan parameters may be needed to 
compensate for the artifact. Additional information regarding image artifact should 
be included if you wish to indicate in your medical device labeling that diagnostic 
MRI is possible within a specified distance of an implanted medical device.
10.Instructions to be followed before and/or after an MR exam (e.g., patient preparation, 
medical device checks or programming for special modes).
11.Additional instructions or information essential for safe use in the MR environment. 
(e.g., information about scanning patients with other devices. For example: Patients 
who have other MR Conditional devices can be scanned as long all the MR 
Conditional scan parameters for each of the devices are met. Do not conduct an MRI 
scan if any conditions for safe scanning for any device cannot be met.; information 
for active medical devices about how to proceed when an alarm signal is present)
12. A statement such as: If information about a specific parameter is not included, there 
are no conditions associated with that parameter.
For item 7 above although the actual implant heating values from bench testing or 
computational modeling are not needed in the labeling, these values will inform the safe MR 
exam.
For devices that are less than 2 cm long in all directions and at least 3 cm from another 
passive metallic medical implant for which RF induced heating testing was not conducted, 
21 Contains Nonbinding Recommendations
we recommend an SAR of 2 W/kg (Normal Operating Mode) and a maximum scan time of 
one hour after which a cooling period is needed.
For devices that are 2 cm or longer, the labeling should consider whether the intended 
location in the body is near thermally sensitive tissue (i.e., brain, eyes, neural tissue, testes, 
and ovaries). For devices contacting thermally sensitive tissue, the safe continuous scan 
period is restricted compared to devices intended for thermally less sensitive tissue as 
described below:
Devices adjacent to thermally sensitive tissue: 
If the device is expected to heat adjacent tissue up to 2 C in 15 minutes in Normal Operating 
Mode, it can be labeled for 1 hour of continuous scanning in Normal Operating Mode 
without a cooling period.43,44 A cooling period is needed for longer scans. For devices that 
heat adjacent tissues more than 2 C in 15 minutes, the manufacturer should provide an 
appropriate continuous scan time with cooling period.
Device adjacent to thermally less-sensitive tissue:
If the device is expected to heat adjacent tissue up to 4 C in 15 minutes in Normal Mode, it 
can be labeled for 1 hour of continuous scanning in Normal Operating Mode without a 
cooling period.45,46A cooling period is needed for longer scans. For devices that heat 
adjacent tissue more than 4 C in 15 minutes, the manufacturer should provide an appropriate 
continuous scan time with cooling period. 
We recommend you use a table to list the information in items 1-6. Information in items 7-12 
can be included in a table or in another format if that enhances the clarity of the information.
See Table 3 in Appendix 2 for an example of MR Conditional labeling for a passive implant.
See Tables 4a and 4b for an example for an active implant and the conditions for safe 
scanning that could be clearly provided in a table. To further enhance clarity, we recommend 
including a diagram showing the allowable scan regions with each table. Information that is 
more clearly provided in a non-tabular format can be included after the tables, for instance 
instructions to be followed before and/or after an MR exam (e.g., patient preparation, 
medical device checks or programming for special modes) and additional instructions or 
information essential for safe use in the MR environment. 
MR Conditional medical devices anticipated to remain outside of the MR system bore
43Shrivastava D, Utecht L, Tian J, Hughes J, and Vaughan JT, In Vivo Radiofrequency Heating in Swine in a 3T (123.2 
MHz) Birdcage Whole-Body Coil, Magn Reson Med., 2014, Vol. 72, No. 4, pp. 1141-50. 
(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4041852/)
44Tian J, Shrivastava, D, In Vivo Radiofrequency Heating in a 3T MRI Scanner 2018, in Theory and Applications of Heat 
Transfer in Humans, Editor Shrivastava D, John Wiley and Sons, Chichester, West Sussex, UK.
45Shrivastava D, Utecht L, Tian J, Hughes J, and Vaughan JT, In Vivo Radiofrequency Heating in Swine in a 3T (123.2 
MHz) Birdcage Whole-Body Coil, Magn Reson Med., 2014, Vol. 72, No. 4, pp. 1141-50. 
(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4041852/)
46Tian J, Shrivastava, D, In Vivo Radiofrequency Heating in a 3T MRI Scanner 2018, in Theory and Applications of Heat 
Transfer in Humans, Editor Shrivastava D, John Wiley and Sons, Chichester, West Sussex, UK.
22 Contains Nonbinding Recommendations
Labeling for MR Conditional medical devices anticipated to enter the MR environment but 
remain outside the bore of the MR system should provide the conditions under which the 
medical device can be safely used. Because of variability between MR systems, the MRI 
safety information should include positional conditions in terms of maximum static magnetic 
field (also known as gauss line restrictions) [e.g., 20 mT (200 gauss)] rather than distances. 
The MRI safety information for active medical devices should include information directing 
the user on how to proceed when an alarm signal is present.
The MR Conditional symbol should be included directly on the medical device when 
possible, and if space permits, the conditions for safe use in the MR environment should also 
be included on the medical device in a supplementary sign as defined in ASTM F2503. At a 
minimum the supplementary sign should include the gauss line restriction. As appropriate, 
you should also include statements such as projectile hazard or equipment operation may 
be affected in the supplementary sign. 
Table 5 in Appendix 2 shows an example of the MR Conditional labeling for a medical 
device anticipated to be used in the MR environment and outside the MR system bore. 
Appendix 2 also includes an example of MR Conditional labeling that we recommend you 
include directly on the medical device for a medical device that is anticipated to be used in 
the MR environment but not anticipated to enter the MR system bore.
Safety in MRI Not Evaluated 
For passive implants, passive medical devices that are fastened to or carried by a patient, and 
passive medical devices anticipated for use in the MR environment that have historically not 
provided any information about MRI safety, the following labeling could be used in certain 
circumstances. If used, this information should be included in a section headed MRI Safety 
Information and included in the table of contents if the labeling has a table of contents. We 
recommend you provide a rationale as to why this labeling is appropriate for your medical 
device in your premarket submission. The labeling should include the following information:
The <insert medical device name> has not been evaluated for safety in the MR 
environment. It has not been tested for heating or unwanted movement in the MR 
environment. The safety of <insert medical device name> in the MR environment 
is unknown. Performing an MR exam on a person who has this medical device 
may result in injury or device malfunction. 
You should NOT use the above labeling option if:
 there are any known adverse effects or adverse events due to exposure to the MR 
environment for the medical device or medical device type, or
 the medical device or medical device type has typically been labeled as MR 
Conditional or MR Unsafe (for example, including but not limited to 
cardiovascular stents, intracranial aneurysm clips, endovascular grafts, and 
transprostatic tissue retractors), or
 this is a new medical device type, or
23 Contains Nonbinding Recommendations
 the medical device contains ferromagnetic material(s), or
 the medical device is an active medical device, or
 the medical device is a partially implanted medical device.
If you are uncertain whether it is appropriate to label your medical device as Safety in MRI 
Not Evaluated, we recommend that you submit a pre-submission through the Q-submission 
process to obtain feedback prior to submission of a regulatory submission.47
47https://www.fda.gov/regulatory-information/search-fda-guidance-documents/requests-feedback-and-meetings-medical-
device-submissions-q-submission-program
24 Contains Nonbinding Recommendations
Appendix 1. Example of Test Result Summary that may 
be Included in a Regulatory Submission
Medical 
Test  Device  Summary of Test 
Hazard  Method  Acceptance  Configuration  Results and pass/fail  Location in 
Addressed Used Criterion Tested if Appropriate Submission
maximum artifact 
ASTM  for  extended 3 mm from  Volume 2, 
image  F2119 characterization  device for a Gradient  Section 
artifact 07(2013) purposes  40 mm  Echo Scan at 3T 10.3, p. 37
2 deflection at location 
where B =1.52 T and 
magnetically  magnetic force  dB/dz = 4.67 T/m; 
induced  less than  calculated maximum  Volume 2, 
displacement  ASTM  medical device  spatial field gradient =  Section 
force F2052-21 weight 40 mm  30 T/m; pass 10.4, p. 45
ASTM 
F2213-17, 
Low  torque less 
magnetically  friction  than  Volume 2, 
induced  surface  gravitational  no observable torque at  Section 
torque method torque 40 mm  3T; pass 10.5, p. 57
Circularly Polarized (CP) 
body coil,
Max. whole-body 
average SAR of 2 W/kg
ASTM  Temperature rise of 0.5  Volume 2, 
RF induced  F2182- heating less  oC/(W/kg) over 15  Section 
heating 19e2 than 5 C 40 mm  minutes; pass 10.6, p. 65
Table 2. Example test result summary table that may be included in a regulatory submission 
for a passive implant
25 Contains Nonbinding Recommendations
Appendix 2. MR Conditional Labeling Examples
MRI Safety Information
A person with the Star implant may be safely scanned under the following conditions. Failure to 
follow these conditions may result in injury.
Device Name Star implant
Static Magnetic Field Strength (B ) 1.5T or 3.0T
0
Maximum Spatial Field Gradient  30 T/m (3,000 gauss/cm)
RF Excitation Circularly Polarized (CP)
RF Transmit Coil Type There are no Transmit Coil restrictions
Operating Mode Normal Operating Mode
Maximum Whole-Body SAR 2 W/kg (Normal Operating Mode)
Maximum Head SAR 3.2 W/kg (Normal Operating Mode)
2 W/kg whole-body average SAR for 60 minutes of 
Scan Duration continuous RF (a sequence or back to back series/scan 
without breaks)
The presence of this implant may produce an image 
MR Image Artifact
artifact.
Table 3. Example MR Conditional labeling for a passive medical device called the Star 
implant.
26 Contains Nonbinding Recommendations
MRI Safety Information
For Whole-Body MR Examinations: A person implanted with the Star Active Implant System may be safely 
scanned anywhere in the body at 1.5T or 3.0T under the following conditions. Failure to follow these 
conditions may result in injury.
Parameter Condition
Device Name Star Stimulator
Star Lead
Device Configuration Stimulation OFF
Static Magnetic Field Strength (B ) 1.5T and 3T
0
Type of Nuclei 31P (phosphorus)
MR Scanner Type Cylindrical
B Field Orientation Horizontal
0 
Maximum Spatial Field Gradient 25 T/m (2500 gauss/cm)
Maximum Gradient Slew Rate 200 T/m/s per axis
RF Excitation Circularly Polarized (CP)
RF Transmit Coil Type Integrated Whole Body Transmit Coil
RF Receive Coil Type Any
Operating Mode Normal Operating Mode
RF Conditions  For 1.5T MR Scanner: Whole-Body SAR  2 W/kg
For 3T MR Scanner: B   1.7 T; for MR scanners that 
1+rms
do not report B , Whole-Body SAR  1.2 W/kg
1+rms
Scan Duration Scan for up to 30 minutes. Wait 30 minutes before the next 
imaging session.
Scan Regions Any landmark is acceptable
Image Artifact The presence of the Star Active Implant System may 
produce an image artifact. Some manipulation of scan 
parameters may be needed to compensate for the artifact.
Table 4a. Example showing conditions for safe scanning that can be clearly provided in a 
table for an MR Conditional active implant called the Star Active Implant System. Table 4a 
gives conditions for whole-body MR examinations. Information that is more clearly provided 
in non-tabular form may be included after the tables, for instance, instructions to be followed 
before and/or after an MR exam and additional instructions or information essential for safe 
use in the MR environment. 
27 Contains Nonbinding Recommendations
MRI Safety Information
For Head MR Examinations: A patient implanted with the Star Active Implant System may safely receive a 
head scan at 1.5T or 3.0T under the following conditions. Failure to follow these conditions may result in 
injury.
Parameter Condition
Device Name Star Stimulator
Star Lead
Device Configuration Stimulation OFF
Static Magnetic Field Strength (B0) 1.5T and 3T
Type of Nuclei No additional nuclei
MR Scanner Type Cylindrical
B Field Orientation Horizontal
0 
Maximum Spatial Field Gradient 25 T/m (2500 gauss/cm)
Maximum Gradient Slew Rate 200 T/m/s per axis
RF Excitation Circularly Polarized (CP)
RF Coil Type Detachable Head Transmit/Receive Coil ONLY
Operating Mode Normal Operating Mode or
First Level Controlled Operating Mode
Maximum Head SAR 3.2 W/kg
Scan Duration There is no limit on scan duration.
Scan Regions Head Only
Image Artifact The Star Active Implant System is not implanted in the head. No 
image artifact should be seen in a head MRI scan.
Table 4b. Example showing conditions for safe scanning that can be clearly provided in a 
table for an MR Conditional active implant called the Star Active Implant System. Table 4a 
gives conditions for whole body MR examinations. Table 4b gives conditions for head MR 
examinations. Information that is more clearly provided in non-tabular form may be included 
after the tables, for instance instructions to be followed before and/or after an MR exam and 
additional instructions or information essential for safe use in the MR environment. 
28 Contains Nonbinding Recommendations
MRI Safety Information
The <insert device name> may be safely used in the MR environment under the following 
conditions. Failure to follow these conditions may result in <choose one or more of injury or 
serious injury, and/or death.>.
Name/Identification of medical device
Maximum static magnetic field [mT] and 
Do not exceed X[mT] (Y[gauss])
[gauss]
Instructions to be followed before and/or 
after the MR exam
e.g., Additional positional information (e.g., Tether 
device  to  an  immoveable  location  in  the  room; 
Engage brake when not in motion; Fasten device 
to an immoveable location in the room).
Additional instructions or information  e.g., Additional information explaining the given 
essential for safe use in the MR  gauss  line  restriction  (e.g.,  The  device  is  a 
environment projectile  hazard;  Device  operation  may  be 
impacted at field strengths greater than X mT (Y 
gauss)).
e.g., Follow  the  MR  Conditional  labeling  for  all 
accessory devices.
If information about a specific parameter is not included, there are no conditions associated with 
that parameter.
Table 5. Example information to be included in MR Conditional labeling for a medical 
device anticipated to enter the MR environment and remain outside the MR system bore.
Below is an example of MR Conditional labeling that should be included when possible 
directly on the medical device, for a medical device that is anticipated to enter the MR 
environment but is not anticipated to enter the MR system bore. 
Projectile hazard
Equipment operation may be impacted
Do not exceed 20 mT (200 gauss)
29