Turning the Third Edition of IEC 60601-1 to Your Advantage

Medical device manufacturers can benefit from the standard’s risk-based approach

Published: Thursday, January 26, 2012 - 12:02

There are substantial changes in the third edition of IEC 60601-1, and understanding all aspects of them is the key to turning the standard into a benefit for medical-device manufacturers.

This article explains the philosophy behind the major changes in the standard, how these changes will affect device manufacturers, and shares information as to which resources are available to help make the smoothest possible transition to the revised standard, IEC 60601-1—“Medical equipment/medical electrical equipment—Part 1: General requirements for basic safety and essential performance,” published by the International Electrotechnical Commission (IEC).

It is important to begin by understanding that the goal of the IEC 60601-1 revisions was to assist manufacturers in expanding their medical device development. The objective was to design standardized requirements that would demand safety while allowing new technologies and new clinical applications to evolve. To achieve this, the standard’s developers agreed early in the revision process that a fundamental philosophical shift from older standards was needed.

Standards from many years ago were very prescriptive, meaning that they specified exactly what construction was acceptable. For example, an enclosure “Shall be 14-gauge painted steel,” or an insulator “Shall be phenolic.”

Over time, these prescriptive requirements were recognized as being too limiting to the application of new technologies. Thus, standards slowly migrated toward performance-based requirements, where the standard would specify the appropriate level of performance, but the designer could find novel ways to reach this performance minimum. For example, the material of the product enclosure would not be specified, but an impact test would be required to prove that whichever material was chosen was acceptable for the intended use.

The philosophy of the third edition of IEC 60601-1 is the manifestation of the next step in the evolution of standards. It requires designers of medical equipment to analyze the hazards and risks that might come from the use of a device, and then design the device to address those risks. Instead of physical requirements or test requirements, the designer has requirements for analyzing the risk of the device and mitigating the safety hazards. This throws open the door to the use of new ideas and technologies that cannot even be predicted at this time. Ultimately, the philosophy of the third edition is intended to encourage novel and improved clinical applications, resulting in better patient outcomes.

Although some of the new requirements are quite challenging, when one looks at the whole picture the goal is clear: to free up medical device manufacturers. In many instances the standard allows each manufacturer to develop its own level of adoption that is tailored to its specific needs, based on the type of medical devices it designs and manufactures, rather than to be squeezed into a set of regulations that may or may not be applicable for its particular product. The standard’s third edition begins with many of the same basic test requirements as the second edition, but the third edition allows an alternate method through risk assessment to not meet those specific requirements when appropriate.

The third edition of IEC 60601-1 is a complex standard based on risk mitigation that can be a bit overwhelming at first glance. The first thing to understand is that it is based on a philosophy of patient and operator protection that allows for use of novel technologies and treatment modalities. This flexibility in design uses a risk-management approach to enhance operator and patient safety. The most obvious benefit of this is that the standard allows the manufacturer to choose the proper requirements for its device based on its application, rather than on assumptions made in a proscriptive test standard. This translates into high device confidence and a compliance approach that allows maximum flexibility.

Reasons for the change to IEC 60601-1

The IEC is a nonprofit, nongovernmental, international standards organization that prepares and publishes international standards for many electrical, electronic, and related technologies. The purpose of the IEC is to create the standards that ensure high quality in devices and safety for the user.

The main driver for the transition from the second to the third edition came from medical device manufacturers and users interested in a less prescriptive testing and standards approach that did not tell them exactly what to do in testing products. Manufacturers said they would rather have an evaluation approach that let them think about where potential hazards are to the patient and to the operator. The manufacturer could then base its design on assessment of that risk and its mitigation of that risk. Manufacturers believed that this approach would broaden the design spectrum and allow them to use emerging technologies without the need to wait for standards to catch up.

As mentioned above, past standards were often quite prescriptive, giving precise requirements for size, shape, testing, and marking. In some areas this is appropriate, such as when designing electrical plugs that must fit into matching sockets. For these devices, it makes perfect sense to have a fixed set of rules and to comply with them. However, this is not appropriate for medical devices, where the inclusion of new technologies is vital to the continued improvement of patient outcomes. What is needed in medical equipment standards is a flexible way to include these new technologies, with customized demands that are adjusted to the requirements for the device, depending on its use and the risks to the patient and users. A set of regulations that fits only the highest-risk devices is certainly overkill for less critical products, causing a huge financial burden on manufacturers. On the other hand, critical-use devices that do need that extra level of safety regulations could fall through the cracks of a leaner standard, allowing potential problems in the field.

As a result, we have the birth of the IEC 60601 Third Edition, published in 2005 by the IEC. It was driven by manufacturers looking for a faster way to get innovative designs to market. But every good change brings challenges, and the third edition is no exception.

The new standard is truly much more flexible. The downside of that flexibility is that the manufacturer must perform an extremely detailed analysis of dangers, hazards, and risks. Manufacturers are now required to do research into levels of hazard and risk mitigation in order to get their new designs into the market.

To organize the risk analysis required, ISO 14971 is part of the design process under the new standard. While a full description of ISO 14971—“Medical devices—Application of risk management to medical devices,” is beyond the scope of this article, it is valuable to point out the important topics included in this standard from the International Organization for Standardization (ISO).

Here are the major areas, numbered by the clauses and subclauses in ISO 14971:

3 General requirements for risk management
3.1 Risk management process
3.2 Management responsibilities
3.3 Qualification of personnel
3.4 Risk management plan
3.5 Risk management file
4 Risk analysis
4.1 Risk analysis process
4.2 Intended use and identification of characteristics related to the safety of the medical device
4.3 Identification of hazards
4.4 Estimation of the risk(s) for each hazardous
5 Risk evaluation
6 Risk control
6.1 Risk reduction
6.2 Risk control option analysis
6.3 Implementation of risk control measure(s
6.4 Residual risk evaluation
6.5 Risk/benefit analysis
6.6 Risks arising from risk control measures
6.7 Completeness of risk control
7 Evaluation of overall residual risk acceptability
8 Risk management report
9 Production and post-production information

Now medical device manufacturers have flexibility in how they test new product design and development but within a highly structured approach using a risk management process. This structured approach allows each manufacturer to choose the best level and methods of risk-mitigation technology to apply to products based on what the product is, how it will be used, and who will be using it. It is adding a layer, or in some cases layers, of considerations for new designs.

The biggest change

The creators of the third edition have answered the call for additional design and development flexibility, but added a substantial level of required risk assessment to balance this flexibility.

The third edition allows each manufacturer the flexibility to perform testing to each product’s needed risk level. This opens the door to update products and keep pace with new technologies. Designers are open to use more flexibility in actual product design and to take advantage of new power sources. It also aligns the process with the regulatory requirements of both the U.S. Food and Drug Administration (FDA) and notified bodies in Europe, where risk management is a regular part of the device’s submission process. The benefits of the standard’s flexibility are there, but like all benefits, some come with a cost. Depending on what the product is, there may now be several added layers of risk assessment required. Although it may add time to the development, the end result will be a product that has been designed with a focus on balancing the risks of the product’s use with the benefits.

First, it is important to note that most medical device manufacturers have at least some of the pieces in place already. Some will need additional detail in their documentation to fully ensure that all processes applicable to the design, manufacture, and use of any product have considered the risk management based on ISO14971. The end goal is always patient and operator protection; therefore, depending on the manufacturer’s assessment of the product risk, keeping highly detailed documentation on how the assessment was calculated and how the validation process was completed is required.

Other important changes

Patients are often at a heightened level of risk, especially from an electrical hazard perspective. This is because they may be comatose or sedated, and may be unable to move away or react to a hazard. They may have other medical devices or often multiple devices connected directly to their bodies, such that the skin resistance is reduced. All of these situations bring heightened risk, and the medical standard 60601-1 has always called for devices to have tight controls that take the patient’s special situation into consideration.

However, the operator of a medical device is quite different. The person is awake and alert, has normal body impedance, and is typically trained in the use of the devices. The risks to operators are different than those to patients.

As a result, the level of protection provided to a patient must be considerably higher than that for the operator, and there is delineation in the standard between patient protection, which has a very high level of demand, and operator protection, which has a slightly lower level of demand.

The new edition of the standard has changed some requirements to adjust to these differences between patients and the operator. Patient protections are kept very high, and the operator protections have been scaled to reflect the operator’s situation. Thus, the third edition has requirements for the means of operator protection (MOOP), which is less strict than the means of patient protection (MOPP).

The MOPP/MOOP requirements are more complex than the second edition of IEC 60601-1, so it can lead to some confusion if device designers do not truly understand the new requirements. For example, the MOOP requirements for operator safety may suggest the use of cost-saving, off-the-shelf components such as an IEC 60950-compliant power supply. This may be appropriate, but must be very carefully analyzed to ensure that any risk to the patient is managed.

Another big change is the addition of essential performance into the standard. Essential performance is now a full part of the evaluation of the safety of the product. It was somewhat applicable to some products tested to the second edition in the past, but now it is very obviously included, and the risk analysis that the manufacturer performs will need to address it. The third edition requires the manufacturer to state what parts of the product’s function are essential to patient outcomes, and what the level of risk is if they do not perform at that level.

A basic example is a medical product that provides life support. It is not enough that the device be electrically and mechanically safe. The essential performance of the device is to maintain function in order to keep the patient alive. Loss of power to the device is a potential risk to its essential performance, and the manufacturer must assess the patient outcome if power is lost. In this case, a backup power system is probably needed.

It is not enough for the product to work safely when turned on, but it must effectively do what it is intended to do.

Systems of medical products

Many medical devices are no longer stand-alone products. They often are connected with other devices with power links and communication links to form systems of medical products. In the earlier second edition of 60601-1, this was covered under the systems standard 60601-1-1. But as more medical devices were used in systems, it became clear that the requirements for systems needed be fully integrated into the basic requirements in 60601-1. This has been done in the third edition, and so the second edition 60601-1-1 standard is now obsolete because all the systems requirements are in the main standard.

The testing of interconnected systems is now a prominent part of the required evaluation for the third edition. For the evaluation of a system, everything that works together must be connected as intended and assessed for risk to the patient. The manufacturer cannot simply check one product that goes into a full system; even if the products are provided separately, they still need to be evaluated together as a working system.

Programmable systems and software

In a similar way as with the systems discussed above, programmable systems and software in medical devices have become much more common as technology becomes more available and the benefits became clear. These programmable systems control user interfaces, alarms, infusion rates for pumps, and temperature control for the human body, among many other aspects. To adjust for the huge growth in programmable systems, the requirements for these systems are now directly in the base standard 60601-1. The past standard for programmable electrical medical systems, 60601-1-4, has been deleted.

Wireless

Wireless communication is an area of explosive growth for medical devices. Systems of medical electrical equipment now include several different possible wireless protocols together with their wired communications systems. The equipment communicates with other devices, but they may also interfere with each other. They may react negatively because of interference with other medical devices or nonmedical devices in the clinical setting. Even portable games, cell phones, and ambient RF noise can pose problems. These are all part of the concerns for risk and safety with medical devices in the third edition of IEC 60601-1. When the manufacturer analyzes the risks of the environment and its device per IEC 60601-1 Third Edition, it must assess the impact of wireless interference or “crosstalk” on the safety and essential performance of its device.

Understanding collateral standards

The base standard of IEC 60601-1 covers general requirements for all electrical medical devices. There are additional “horizontal” standards that may apply to all devices, and these are called “collateral standards.” Two of the best examples are 60601-1-2 EMC, which can be applied to virtually every device; and 60601-1-8 alarms, which is applied to any device that uses a visible or audible alarm to address a risk.

Understanding particular standards

Another part of the series of medical standards is what is called a particular standard. A particular standard is aimed at a very specific product or modality. For example, ventilators are covered by IEC 60601-2-12. Particular standards add or subtract requirements from the base standard to address unique aspects of the equipment. There are approximately 50 particular standards.

When standards are updated and new editions are published, not everything updates at the same time. Older standards for many areas will still be in effect along with their “daughter” standards that are correlated with the new third edition.

Only about 15 of the particular standards have been revised to correlate with the third edition. These particular products are required to meet the new particular standard and the third edition of the base standard. But for devices where the particular standard has not been updated, their requirements stay with the second edition. So a substantial number of devices do not yet need to meet the third edition, but it is best to be aware of the changes to be prepared for the future. Some manufacturers may get more time to comply, but they will need to make the transition eventually.

What is the actual benefit to the design process?

Opening up the design process to the latest developments in technology also means looking at both the worst-case and residual-risk assessment for any product. It is the price to pay for design freedom.

The actual benefit is in design flexibility. Although it is not necessarily easy flexibility, it does allow the manufacturer to analyze where the dangers are and balance them with the rewards right from the start. The classic case would be when a modality or treatment is very risky but without it, the patient dies. The manufacturer, clinician, and even the patient might say, “I am willing to accept a 20-percent risk of death when I use this modality because the risk of not using it is 100-percent certainty of death.” Granted, it is never an easy decision, and this is an extreme example, but the whole concept supports the idea of balancing risk with the benefit while developing new technologies for diagnosis and treatment. This concept allows designers to move past just the clinical choices that are made by physicians to the actual design decisions that are made by manufacturers. It allows them to embrace the future and wherever new technology leads patient care. It opens many doors to innovative design and the use of leading-edge developments using new electronics, communications, and other types of components and systems.

Impact on test and certification bodies

IEC 60601-1 Third Edition also affects those handling certifications. Now evaluation and testing will encompass much more than the traditional electrical and mechanical realms. They are also going into new territory; risk management, essential performance, and usability are all part of the picture. This has required test and certification bodies to upgrade their methods and personnel to be able to certify devices to the new standards. They must understand and be able to work with manufacturers to apply ISO 14971, sometimes consulting with experts who are experienced in risk management, and biomedical experts who understand the necessary types of medical electrical equipment.

Effective dates for the third edition

The European Union (EU) is leading the push, and all medical device manufacturers who are selling to EU territories currently, or plan to sell new devices into that market, should make the change as soon as they can. Beginning June 1, 2012, the EU will no longer accept the second edition. This includes existing devices already tested to second edition standards. The device must be reevaluated to the third edition, including risk management to ISO 14971, with appropriate documentation.

Canada has already published its national version of IEC 60601-1 Third Edition as CAN/CSA C22.2 No. 60601-1-08. Health Canada will no longer accept the second edition beginning on June 1, 2012. However, it is expected that device submissions to Health Canada prior to this transition date will not be withdrawn.

In the United States, the FDA has announced that both the IEC and AAMI versions are on its list of consensus standards. The withdrawal date for the second edition is June 30, 2013. Device submissions to FDA prior to this date will not be withdrawn, but the third edition is already being accepted by the FDA for many products.

The chart in figure 1 details the transition timeline as it applies to specific geographical areas.

Implementation dates for IEC 60601-1 Third Edition

In 2005, the third edition of IEC 60601-1 was published. This was followed with publication by three other major standards bodies:

 Figure 1: Transition timeline to the third edition of IEC 60601-1 as it applies to specific geographical areas

Transition dates for these standards vary by the geographical market, as shown in figure 2:

 Figure 2: Transition dates

[1] U.S. FDA Website
http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/detail.cfm?standard__identification_no=28193

[2] Email dated 28-Feb-2011 from Mr. B. Pasquet, Office of Technical Programs and Coordination Activities
OSHA - Washington, DC.

[3] Website for European Union Official Journal: http://ec.europa.eu/enterprise/policies/european-standards/documents/harmonised-standards-legislation/list-references/medical-devices/index_en.htm

[4] Health Canada website. http://www.hc-sc.gc.ca/dhp-mps/md-im/standards-normes/notice_iec_60601_avis-eng.php

Consequence of inaction

Compliance with the third edition of IEC 60601-1 is a must if any medical device manufacturer wants to stay in the market. Over time, each geography and market will make a transition to this approach, and will embrace the risk-management approach to medical device conformity. although there is still the possibility that manufacturers will be able to keep producing and selling existing product for certain markets that have no upgrades at all, that will be its own nemesis. All products must eventually keep up with current technology, or they will literally drive themselves out of the market.

Help in making a smooth transition

While there are many product-safety laboratories that are used to working under past standards, not all are credentialed as a notified body for the Medical Device Directive (MDD) or have the knowledge of ISO 14971, to be cooperative guides for manufacturers making the change to the new device safety standards.

A qualified national certification body (NCB), such as TÜV Rheinland, and a certified body testing laboratory (CBTL) can offer help navigating through the new approach and requirements. This can be a great help to any medical device manufacturer looking to discover the greatest advantages locked within the third edition.

However, while any qualified regulatory, test, and certification body can help reduce the confusing issues, all must draw a line between helping the manufacturer to develop testing processes and validation of tests, and providing product redesign help. They can’t overstep limits and provide actual device design or engineering advice.

Conclusion: making a smooth transition

The most important thing while assessing these changes is for each medical device manufacturer to clearly understand the changes involved and to begin the transition as early as possible. This is simply common sense and good marketing. The earlier the transition is started, the better the company will be able to manage all the aspects of compliance it needs to implement. It is best to do this while implementation is not urgently time-critical.

Understanding the intricate details of IEC 60601-1 Third Edition’s main changes and the reasons behind them will help make the transition easier. Knowing which deadlines affect which geographies, markets, and specific devices is key. Finally, knowing where to turn for help is absolutely necessary. There is no reason to fall into confusion when there are sources ready and able to help medical device manufacturers make a smooth transition to the third edition.

With a philosophy based on risk management, the third edition of IEC 60601-1 offers challenges, but also great advantages to medical device manufacturers if they understand the standard and use it to their advantage.

About The Author

Dale Hallerberg

Dale Hallerberg is the technical manager for medical product testing at TÜV Rheinland of North America. His bachelor of science in electrical engineering is from the University of Illinois. He has more than 25 years experience in product safety testing and electrical safety research. He is a member of the AAMI Electrical Section, and is active on the IECEE Risk Management Task Force. He is also part of the development team for the third edition amendment 1 of IEC 60601-1—“Medical equipment/medical electrical equipment—Part 1: General requirements for basic safety and essential performance,” published by the International Electrotechnical Commission (IEC).