Field safety notices: guidance for manufacturers
Source: gov.uk (2025-06-16)

How to write clear and effective field safety notices (FSNs)  for medical devices.

Manufacturers must take field safety corrective actions (FSCA) to prevent or reduce the risk of a serious incident in relation to a device which has already been placed on the market or put into service.

You should communicate details of FSCA to customers and users using a field safety notice (FSN). The UK medical devices regulations state that after “submitting the initial report and proposed notice… the manufacturer must implement the FSCA as soon as possible and monitor its progress.”

You can find out more about writing and distributing FSNs in our guidance on post-market surveillance (https://www.gov.uk/government/publications/medical-devices-post-market-surveillance-requirements).

This guidance for manufacturers provides supplementary information and advice on how to produce and distribute effective FSNs.

Good traceability

You should keep records to help trace your distributed product. This should include:

records of medical devices by manufacturing date and batch, version or serial number

unique device identifiers (UDI)

keeping traceability of medical devices directly supplied to users and distributors

Contracts with distributors should include keeping onward traceability records to end users and agreements on information sharing as far as is practicable. If distributors are not willing to share customer lists with you, your contract should require them to do so directly with the MHRA on request. Responsibility for ensuring the communication reaches end users remains with the manufacturer.

For connected devices, software and applications (apps), consider:

how you can use the technology to aid traceability

how to distribute the message of FSNs

how to enable updates to be delivered to the field

When supplying to large organisations such as NHS trusts and boards, recording the address and name of the responsible department is important for traceability. Where possible, record the name of the user or person responsible for the device as well as anybody responsible for the purchase.

In addition, when supplying NHS organisations, recording the name of the NHS trust or board will enable you to identify the medical device safety officer (MDSO) in healthcare establishments throughout England and Wales, Incident and alerts Safety Officers (IASOs) in Scotland and Medical Device Liaison Officers (MDLOs) in Northern Ireland to contact. This will help you target your communication to get maximum replies to your FSNs.

FSN content

Manufacturers can use this template to write FSNs (https://mhra-gov.filecamp.com/s/d/FSN_template). Where a section of the template does not apply to your product, you can remove it.

You should read the FSN template Q&A (https://mhra-gov.filecamp.com/s/d/FSN_QA) before completing your notice.

There is also an FSN customer reply template (https://mhra-gov.filecamp.com/s/d/FSN_customer_reply_form_template) and an FSN distributor/importer reply template (https://mhra-gov.filecamp.com/s/d/FSN_reply_distributors_importers).

The FSN should be on a company letterhead, be written in English and include:
- a clear title, with “Urgent FIELD SAFETY NOTICE” followed by the commercial name of the affected product, an FSCA identifier (for example, date or FSCA reference number) and the type of action
- specific details to enable the affected product to be easily identified, for example, type of device, model name and number, batch/lot or serial numbers of affected devices, part or order number and UDIs where available - we recommend that the manufacture dates are also included for ease of identification
- a factual statement explaining the reasons for the FSCA, including a description of the device deficiency or malfunction, clarification of the potential hazard associated with the continued use of the device and the associated risk to the patient, user or other person and any possible risks to patients associated with previous use of affected devices.
- how to identify an affected device
- method of recovery, quarantine, disposal or modification of device
- review and implementation of additional risk mitigation measures
- recommended review of patient’s previous results or patient follow up, for example, implants, IVD
- timelines for completion of these actions
- a request to pass the field safety notice to all those who need to be aware of it in the organisation and to maintain awareness over an appropriate defined period
- if relevant, a request for a copy of the field safety notice to be passed on to all organisations to which any affected devices have been transferred, and for the details of onward distribution of these devices to be given to the manufacturer
- if relevant, a request that the recipient of the field safety notice alerts other organisations to which incorrect test results from the use of the devices have been sent, such as failure of diagnostic tests
- confirmation that the MHRA has been advised of the FSCA
- contact point for customers how and when to reach the designated person. This person should be either the manufacturer if UK based, the UK responsible person or Northern Ireland authorised representative
- an acknowledgment form for the receiver
Do not include any comments and descriptions that attempt to:
- play down the level of risk in an inappropriate manner
- advertise products or services
Maximising efficacy of FSN communication

Write the FSN in a clear style and at an appropriate level for the intended audience. Remember that in some cases patients will read the notice, so avoid jargon or unnecessary technical language.

The risk to the user is the key element of the notice. Make it clear what the problem is and what the recipient must do.

Do not delay sending an FSN because you are waiting to include information on the cause of the problem. In such circumstances, there is the option to send a follow-up FSN.

Manufacturers must submit their initial FSCA report and draft FSN to the MHRA before sharing with customers (except for urgent FSNs). This is so we can provide advice on the FSCA implementation strategy or comments on the proposed FSN. If you receive no response within 5 working days of submitting the draft, you should circulate the FSN to your customers. If the action required to protect patient safety is urgent, you can circulate the FSN to your customers without waiting the 5 working days for a response from MHRA.

The initial FSCA report and proposed FSN must be submitted via MORE. If the manufacturer is in contact with an MHRA benefit risk assessor, it can be helpful to send them a copy for speed of review.

You should issue the FSN, with the crucial acknowledgement instructions, as soon as possible after the final version has been agreed.

These are some of the common problems in FSNs:

missing lot numbers

too much jargon

badly explained or missing instructions on what to do next

missing detailed description of the problem

missing explanation of how the problem affects the patient

incorrect or missing contact details for the UK

missing acknowledgment form

final FSN has not been signed or dated

poor translations – we suggest asking your UK responsible person or Northern Ireland authorised representative, or importer or distributor in the UK to check the English if this could be an issue

In your final version FSN we are looking for the following:

the correct contact details for the UK

only generic information about the recipients - do not use a sample with an individual’s name or address on it

include covering letters in the FSN

send it to us as a single PDF file with all the relevant information rather than separate files with versions of FSNs (such as one aimed at distributors and another at customers)

the PDF must not be a scanned version of a paper document because it cannot be searched for serial numbers, model numbers and similar information

the UDIs of the affected devices, preferably on the UDI device and header Excel spreadsheet

if possible, include NHS supply chain codes to help your customers decide if they have your product in stock

if the FSCA covers all lots, state this as well as listing all the numbers

We publish weekly lists of FSNs that affect the UK (https://www.gov.uk/drug-device-alerts) which are seen by over 10,000 subscribers.

Inclusion of unique device identifiers

The FSN must be sent in a format that enables customers to search for UDI information (wherever available), catalogue numbers, model numbers and LOT numbers. We consider it best practice to include unique device identifiers (UDIs) in your field safety corrective action (FSCA) communications.

We have worked with GS1 (https://www.gs1uk.org/) and HIBCC (https://www.hibcc.org/) to produce the following templates for the incorporation of detailed device information in field safety notices (FSNs) and we encourage you to use these.

If you use GS1 UDIs, use the GS1 UDI device and header spreadsheet (https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/885597/GS1_UDI_Device_and_Header_Spreadsheet_.xlsm) . The GS1 recommendations on FSCA and recalls using unique device identifiers and GS1 standards (https://www.gs1uk.org/sites/default/files/061119_Field_Safety_Corrective_Actions_document.pdf) provides background information and details on how to fill in the spreadsheet. (https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/885597/GS1_UDI_Device_and_Header_Spreadsheet_.xlsm)

If you use HIBCC UDIs, use the HIBCC UDI device and header spreadsheet (https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/885598/HIBCC_UDI_Device_and_Header_Spreadsheet.xlsx) .

Effective targeting of FSNs and maximising response rates

The UK medical devices regulations state that “the manufacturer must take all reasonable steps to ensure the field safety notice is sent to users of the device”.

The MHRA does not stipulate the method of distributing FSNs. The key element in maximising response rates is to make sure the right people know that the FSN is urgent and needs a response.

A ‘read receipt’ of an email is not acceptable proof of acknowledgement of an FSN because it does not prove that the FSN has been read and acted on. Some companies are now using an e-signature portal as confirmation that FSNs have been received, and acted on, by the organisation. We encourage this route of distributing FSNs.

Registered post only proves that the FSN arrived at its destination, not that it has been read and acted on by the intended recipient.

Using the network of medical device safety officers (MDSO) in healthcare establishments throughout England and Wales, Incident and alerts Safety Officers (IASOs) in Scotland and Medical Device Liaison Officers (MDLOs) in Northern Ireland can help you get replies to your FSNs. You can access the list of contacts through an account within our manufacturer’s online reporting environment (MORE) (https://aic.mhra.gov.uk/).

The MDSO/IASO/MDLO contact details spreadsheet is updated on a regular basis. If you do not receive a response from an MDSO, IASO or MDLO, please report this to MHRA.

MDSOs, IALOs and MDLOs must be registered with the MHRA and part of their role is to act as an additional senior point of contact for manufacturers and support local actions on FSNs. Although not all healthcare organisations have an MDSO, IALO or MDLO, over 95% of NHS organisations do, so it is a great advantage to include them when sending FSNs to your customers.

The MHRA has a flyer that explains FSNs (https://www.gov.uk/government/publications/field-safety-notice-fsn-what-it-is-and-why-its-important) and why they are important, which manufacturers can send to their customers to help achieve target reconciliation on responses.

The manufacturer’s FSCA strategy

The FSCA strategy will need to specify whether a general public warning (advertisement, a helpline number for 24 hour access to further information or media release) is needed and whether to use more specialised news media. The latter can allow targeting of specific segments of the population (for example, customers signed up to receive updates from manufacturer websites or loyalty schemes) to prevent unnecessary public anxiety and advise that consultation between patients and their healthcare professional is essential.

Whichever method is used, manufacturers should inform the MHRA first and send us a draft copy for comment. There is advice on advertising and using the media in the PROSAFE Corrective Action Guide (https://prosafe.org/images/publications/Corrective_Actions_GuideAnnexes.pdf).

For FSNs relating to software devices published on app stores, a summary of the FSN should be displayed in the information on the app store and, where possible, at the app’s start-up. If the full FSN cannot be displayed, a link to the full text should be made available in-app. It is not acceptable to fix a software issue without issuing an FSN to explain the action taken.

Confidentiality of FSNs

The MHRA keeps information from manufacturers on proposed field safety corrective actions (FSCAs), including draft copies of FSN, confidential as required by the Medical Devices Regulations (SI 2002 No 618, as amended) (UK MDR 2002). Once a manufacturer has issued a final FSN to customers, it is no longer treated as confidential because it is in the public domain.

The MHRA has agreements in place with other international regulatory authorities, where we circulate notifications about FSCAs (in confidence) to promote co-ordinated actions between international regulatory authorities.

What the MHRA does when there is an FSCA

Where there is doubt, the MHRA will provide its interpretation of whether the action proposed by the manufacturer falls within the definition of an FSCA and will give advice on FSNs and associated FSCA strategies.

As soon as possible after we receive sufficient information from the manufacturer, we review the details of every FSCA . We expect manufacturers to reply quickly to queries about FSCAs. Delayed replies increase the likelihood of the MHRA publishing separate advice to the health service in the interests of protecting public health. It may also lead to the MHRA initiating legal compliance action.

Circumstances where the MHRA might have to issue separate advice include the need to:

supplement information provided by the manufacturer, for example, when the message of the FSN is not clear or where additional advice is needed

bring the FSCA to the attention of a wider user base than that contacted directly by the manufacturer, for example, to target different or additional professionals

notify chief executives of NHS organisations or other management personnel, for reasons of clinical governance, of information being issued directly to healthcare professionals

issue an MHRA statement where a safety issue has sufficiently high profile that the health service would expect it

help ensure the message gets to everyone affected when a very large number of customers and centres are affected, where there is a possibility that devices may have been moved between healthcare providers or centres without the knowledge of the manufacturer or distributor

give different advice to that provided by the manufacturer, although through negotiation we try to avoid this wherever possible

The manufacturer, or their authorised representative, will almost always get the opportunity to comment on the draft of any safety-related notice that the MHRA produces.

For FSCAs with public, media or a particular health interest, the MHRA will liaise with colleagues in the Department of Health and Social Care and with the manufacturer to prepare information for general release. Media statements should be worded to minimise any public alarm. Where necessary, UK health ministers will be kept informed.

The MHRA will agree appropriate milestones with the manufacturer or authorised representative for receiving FSCA status reports, including a final report. We examine all the reports from the manufacturer and keep an ongoing assessment of the effectiveness of the FSCA action. This may include further referral to the weekly management meeting.

Where an FSCA is initiated following a report of an incident submitted to the MHRA, we will communicate the outcome of the investigation to the person who sent us the report. In the interests of worldwide patient and user safety, we may also provide copies of MHRA safety warnings issued to the health service in the UK to other regulatory authorities.

Our FSN review and monitoring process

FSCA and FSN logged and initial email sent to manufacturer from AIC requesting information about the action being taken.

FSCA assigned to benefit risk evaluation assessor (BRE assessor), who conducts initial review of safety message and required actions. Therapeutic area group meeting reviews FSCA where required.

BRE assessor may ask for more information from manufacturer or seek clinical opinion.

Information on reconciliation and long-term corrective and preventive action (CAPA) received from manufacturer in response to initial email from AIC, and/or request from BRE assessor.

BRE assessor completes assessment including recommendations for MHRA actions relating to the FSCA.

BRE assessor completes the actions agreed, for example, continue to monitor, or publish safety communications.

Field corrective actions

Although they are outside the scope of the notification requirements of the UK MDR 2002, the MHRA encourages manufacturers to deal with field corrective actions (FCAs) in a similar way to FSCAs.

A field corrective action may arise from a more minor issue that does not pose a risk of death or serious injury.

Examples of FSCA and FCA

Examples of field actions considered to be FSCAs

Example 1

A manufacturer identifies that water used in the manufacturing process is contaminated, and all devices manufactured using this process are potentially contaminated. The investigation included consideration of the type of contamination, the causes of the contamination, and the impact use of a contaminated device could have, taking into account different users.

Rationale: there is potential for serious injury should a contaminated device be used.

Example 2

A manufacturer identifies that diagnostic kit for detecting antibodies impacting on fertility processes within human semen or serum has the potential to produce false negative results.

Rationale: any corrective action(s) taken by the manufacturer to reduce the risk of direct or indirect harm associated with the use of a ‘defective’ diagnostic kit should be reportable. This is especially true in the cases where patient follow up measures are required.

Example 3

The manufacturer updates the instructions for use to include a new warning to mitigate a serious risk to the user.

Rationale: the purpose of the new warning is to prevent serious injury to a patient or user.

Example 4

Following reports that a Heaf test seemed to give an abnormally high level of ‘false negative results’, the manufacturer identified that, although it was performing to specification and requirements, the firing mechanism could be interrupted if it was not handled in a specific way. The instructions for use supplied with the device did not clearly identify this handling requirement. The manufacturer changed the instructions so that the handling of the unit was clearly highlighted in both text and diagram form.

Rationale: there is potential for misfired units to give rise to false negatives, which in turn could result in inappropriate tuberculosis immunisation.

Example 5

Sterilisation services are provided for a manufacturer by a third-party supplier. Devices are found not to have been sterilised in line with the documented, validated process. The investigation included consideration of the impact use of an unsterile device may have as well as the impact removal of product from the market would have on supply.

Rationale: there is potential for serious injury should an affected device be used.

Example 6

A manufacturer of a syringe pump identified a small risk that pumps within a range of serial numbers may not alarm if the syringe plunger clamp was left open. The manufacturer issued instructions on detecting and correcting the problem. Instructions on checking the ‘Clamp Open’ detection mechanism during routine maintenance were also added to the service manual.

Rationale: there is potential for serious injury as a result of over- or under-infusion.

Example 7

A manufacturer identified that due to a battery defect, the rate of battery depletion towards the end of service life of one of their pacemaker models was more rapid than originally anticipated through accelerated testing. There were no un-implanted units remaining with distributors or in hospital supplies available for return to the manufacturer. The manufacturer issued written advice to clinicians following patients implanted with these pacemakers, emphasising the need to schedule clinic visits more frequently than indicated in the physicians’ manual supplied with the product, to check the pacemaker battery status.

Rationale: failure to detect early signs of battery depletion would risk the patient losing pacing therapy.

Example 8

A test for detecting bacterial antigen in cerebrospinal fluid is found to cross-react with another bacterium which causes meningitis.

Rationale: this could result in the wrong antibiotics being administered.

Example 9

Following reports of users falling from powered wheelchairs due to failures of castor assemblies it was found that the instructions for use did not include adequate user checks and regular maintenance requirements to ensure that the castors could continue to operate correctly. The manufacturer revised the instructions for use and incorporated new requirements for user functional checks and regular maintenance.

Rationale: there is potential for serious injury as the result of a fall.

Examples of field actions not considered to be FSCAs

Example 1: general medical device

A manufacturer places an incorrect expiry date of 18 months on the labelling of a batch of product. The supported shelf life is 2 years. The manufacturer chooses to send new labels with the correct expiry date to customers.

Example 2: out-of-box failure

A product is shipped with a reagent missing. Users cannot run the test without it. The manufacturer exchanges distributed product for complete test kits.