The reasons why medical devices often fail to pass regulatory requirements with flying colours are far from complex but, nevertheless, can result in unnecessary delays and costs. Addressing these potential failures early on pays dividends, explains Intertek’s Anna Wildner, who shares her expert insights on medical device testing and how to speed through the regulatory approval process
Anna Wildner is the Medical and Laboratory Project Manager at UK-based Intertek’s testing facility, where she is responsible for operations, client relations and all aspects of project delivery. The Intertek lab, which has been involved in medical device testing for more than 20 years, evaluates a wide range of products from simple wound therapy systems to complex machinery such as linear accelerators for critical cancer care. The lab is equipped and accredited to test the full suite of IEC 60601 design standards including home healthcare, usability and software, as well as 26 particular standards.
More than 90 per cent of medical electrical devices fail to comply with appropriate standards and regulations on their first submission. Manufacturers are finding that, despite their preparations, the compliance process for the extended requirements of the IEC 60601-1 (third edition) standard takes longer than with any other electrical product. When a device has to be redesigned because it fails to conform to these standards, it often results in long and costly delays. By detecting errors early in the design and manufacturing process, organisations see the benefit of getting their device to market on time and on budget.
Wildner, who has worked in medical device testing and certification for eight years (four at Intertek), believes that investing time and resources in best practices can help manufacturers to get devices through the compliance process more quickly.
‘Following the change to the medical device standard IEC 60601-1 from the second to third edition, our lab has been busier than ever with medical evaluation projects that are even more complex than before,’ Wildner explains. ‘While the standard’s second edition focused on the device’s basic safety, the third edition introduced the concepts of risk management, essential performance, usability and software. Basic safety is largely addressed as before, by testing,’ she continues. ‘However, essential performance can’t be covered in the standard by testing as it will be different for each product, so that’s where risk management comes in. Each project covers a robust review of the client risk management file (RMF) and involves the client more than ever before.
‘To discover a failure at the end of the development process can be very costly, as many of our clients find out. For manufacturers, this means that the product must be redesigned and the RMF must be reworked,’ she adds. ‘The consequence is delayed market access, lack of sales and the additional cost of redesigning the product.’
Intertek offers a design review service where it works closely with its clients to explain the standard’s requirements before the project is submitted. The lab’s staff have found that design engineers are reluctant to participate in IEC 60601 training, resulting in products coming into the laboratory that are state-of-the art medical technology, but don’t meet the standard’s requirements and therefore need to be redesigned.
Design engineers often say they aren’t interested in medical standard training because they are more focused on the equipment’s design and functionality. This can cause problems for investors, as it takes an average of four to five months for non-conforming medical device to be completed, as opposed to only four to five weeks turnaround time for a compliant product, as they don’t need to be redesigned and re-documented.
Here are the 10 most common compliance failures for medical devices (and Anna Wildner’s thoughts on them):
‘The most frequent source of problems for electromagnetic compatibility (EMC) is related to the radio frequency emissions being broadcast by the equipment under test.’
‘Failure to correctly mark shipping packaging occurs in at least 90 per cent of products that we test. The standard states that if special measures have to be taken during transport or storage, the packaging must be marked accordingly. Most devices have environmental limits for transport and storage.’
‘Most medical devices don’t have the correct symbols or markings on the exterior or interior. One of the most common mistakes is using the open- book symbol instead of the blue-man symbol when consulting the accompanying documents is a mandatory action. The open-book symbol should be used only when consulting the manual is not mandatory.’
‘Instructions for use (IFU) are wrong in more than 85 per cent of products evaluated. When Intertek receives a product for testing, the IFU must be delivered with the equipment for evaluation. Errors we find during the review include: no explanation of the symbols used on the equipment, instructions that don’t adequately cover user maintenance, accessories and consumables that are not itemised in the manual, or no troubleshooting guide.’
‘More than 80 per cent of the medical devices we evaluate have problems with creepage and clearance distances (C&Cs) – the insulation provided within the device or between parts. Such errors will usually result in product redesign and delays in getting to market.’
‘Red lights are often used for indication purposes, where red should be used only to indicate danger and/or a need for urgent action.’
‘Any components relied on for the product’s safety can be considered critical components. These provide a certain degree of protection to the people and the environment in which a medical product operates, and include items such as plastic enclosures, motors, connectors, fuses, wiring, power supply, transformers, fans, switches, mains cord and plug, and capacitors. All safety critical components need to be third-party approved to their respective standards.’
‘In most medical devices, the cross-sectional area wiring (insulated or printed wiring) is too small for the circuit in to which it is connected. The same dimensions apply for printed circuit boards (PCBs), which are frequently overlooked, especially where power outputs (AC or DC) are provided.’
‘When these tests are applied to equipment, parts or accessories, many products fail leakage current or dielectric strength tests – or both. This means that moisture has entered the product during the cleaning, disinfection or sterilisation procedure and is causing sufficient current to flow to allow the test equipment to detect a fault. This constitutes a non-compliance and needs to be resolved by the manufacturer.’
‘Manufacturers of large equipment with multiple earthing connections frequently don’t comply with the clause that defines the colours for earth conductors.’
‘These 10 examples highlight why it’s well worth investing time and resources in establishing best practices to ensure your medical devices get through the compliance process quickly and to avoid the costly delays incurred if your products need to be redesigned and reworked,’ Wildner concludes.
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