MHRA Publishes 2026 Safety Guidelines for MRI Equipment in Clinical Use
The Medicines and Healthcare products Regulatory Agency has published the fifth edition of its “Safety Guidelines for Magnetic Resonance Imaging Equipment in Clinical Use.”
The document was published in July 2026 and represents a full review and update of the previous edition. The revision history also notes an August 2026 update adding a new cover image, an update from UKAS and various corrections.
Purpose of the Guidelines
The guidelines represent best practice for the safe use and management of magnetic resonance imaging equipment in clinical settings within the UK.
MHRA notes that the document is intended to bring together relevant sources of advice, guidance and legislation on MR safety, provide a single source of advice for the UK context, highlight important considerations before purchase and after installation, and reflect current risks and hazards.
Scope and Key Topics
The document covers the full MRI safety framework, including MRI hazards, exposure management, management of MRI units, patient and volunteer management, equipment lifecycle, cryogens and venting, exposure limits, training, incident reporting and relevant websites.
The table of contents shows extensive coverage of static magnetic fields, time-varying magnetic field gradients, radiofrequency magnetic fields, interaction with medical equipment and foreign bodies, pregnancy and MR exposure, controlled access, emergency procedures, specialist units, procurement, installation, commissioning, maintenance and decommissioning.
MRI Hazards
The guidelines describe hazards associated with the three magnetic fields produced by MRI equipment:
the static magnetic field;
time-varying magnetic field gradients;
radiofrequency magnetic fields.
The document highlights that, for superconducting and permanent magnet systems, the static magnetic field is always present and therefore creates a constant and immediate hazard. Time-varying gradients and RF fields present hazards during image acquisition.
MR Safety Marking and Device Interactions
MHRA refers to ASTM F2503-26 for marking devices brought into the MR environment, using the classifications MR SAFE, MR CONDITIONAL, MR UNSAFE and MR UNLABELLED.
The guidelines also address interaction with medical equipment and foreign bodies, including passive and active implantable medical devices, infusion pumps, ventilators, anaesthetic machines and monitoring equipment. The document explains that MR systems may cause device malfunction, movement, heating, unintended stimulation and other hazards.
Burns, Acoustic Noise and Patient Safety
The guidelines state that RF burns are the most frequently reported MRI-related adverse incident in the UK. They may result from concentrated RF energy deposition at points of conductive contact or coupling, including contact burns, loop burns and proximity burns.
The document also highlights acoustic noise risks. MRI noise can reach levels capable of causing harm during a patient examination, and MHRA reports incidents involving temporary threshold shift, tinnitus and ringing in the ears following exposure without ear protection.
Exposure Management
The guidelines recommend a three-mode approach to MRI operation aligned with IEC and ICNIRP:
Normal Mode;
First Level Controlled Operating Mode;
Second Level Controlled Operating Mode.
These modes address exposure to static magnetic fields, time-varying gradients and radiofrequency magnetic fields, including control of transient sensory effects, peripheral nerve stimulation, whole-body temperature rise and SAR.
Governance and Controlled Access
The guidelines emphasise that safe MRI operation requires clear governance and defined responsibilities.
The employer and MR responsible organisation must ensure trained and appointed MR safety roles, maintain competency and training records, implement safety procedures and ensure safe installation and use of MRI equipment. MHRA recommends day-to-day MR safety management be delegated to a specified MR RESPONSIBLE PERSON.
Controlled access, local rules, emergency procedures and MR authorised person roles are central to preventing unsafe entry into the MR environment and managing risks linked to equipment, patients, staff and visitors.
Equipment Lifecycle and Procurement
The guidelines cover the MRI equipment lifecycle, including business case, site selection, suite design, procurement, installation, acceptance, commissioning, maintenance, decommissioning and replacement.
For procurement, MHRA recommends a multidisciplinary project team including MR radiographers, MR clinicians, MR safety experts, clinical scientists, clinical engineering, estates, infection prevention, IT, finance and external advisors. The document specifically states that an MR SAFETY EXPERT should be included in the project team.
The guidelines also address safety of UKCA, UKNI and CE marked medical devices, off-label use, in-house manufacture, equipment conformity and relevant standards for MRI equipment.
Incident Reporting and Training
MHRA states that incidents and near misses with potential to cause harm should be reported through local systems and, where relevant, to MHRA via the Yellow Card scheme. Incidents should also be reviewed by the MR SAFETY COMMITTEE.
Training is also a major focus. All staff involved in operating or supporting MRI services should receive training before first accessing the MR environment and before undertaking MRI-related duties. Training should be role-specific and proportionate to risk, with annual review and refresher training to maintain competence.
Impact on Medical Device Manufacturers and Healthcare Institutions
For manufacturers of MRI systems, MR-compatible devices, accessories and related software, the updated guidelines reinforce the importance of safe design, clear labelling, risk management, instructions for use, post-market surveillance and alignment with applicable standards.
Manufacturers and healthcare institutions should pay particular attention to:
MR safety labelling and MR conditional use conditions;
interaction between MRI equipment and implanted or external medical devices;
RF burn prevention and conductive loop risks;
acoustic noise and hearing protection;
exposure limits and operating modes;
procurement and site design requirements;
acceptance testing and commissioning;
maintenance and quality assurance;
incident and near-miss reporting;
staff training and competency records.
For healthcare institutions, the guidelines underline that MRI safety is not limited to scanner operation. It requires governance, controlled access, staff training, patient screening, equipment lifecycle management and continuous review of incidents and near misses.
