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Asociación para el Avance en Instrumentación medica  Las normas se elaboran para una variedad de razones. La contención de costos es un objetivo primordial. Si la esterilización segura de una herramienta se puede hacer con menos pasos, el grupo de estándares evalúa la situación para determinar las mejores prácticas.

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La Asociación para el Avance en Instrumentación Médica (AAMI, por sus siglas en inglés), publicó un documento que busca orientar sobre el mantenimiento de calidad a los equipos médicos, para lograr un funcionamiento eficiente de los mismos y garantizar la obtención de resultados confiables en los estudios realizados.

Si bien es responsabilidad de cada centro asistencial en salud diseñar e implementar sus propias indicaciones para el mantenimiento de equipos, las guías EQ89 permiten establecer parámetros internacionales de calidad y adherencia a las instrucciones de uso y revisión de dispositivos médicos que los fabricantes anexan a cada una de sus patentes.

El desarrollo de las EQ89 partió como iniciativa de los Centros para los Servicios de Medicare y Medicaid de Estados Unidos, que en diciembre del 2011 sugirieron a los hospitales nacionales seguir las recomendaciones de manejo de los equipos emitidas por sus fabricantes. Esto motivó a las instituciones y al sistema de salud norteamericano a realizar investigaciones en dicha área, producto de las cuales se escribieron las guías.

A partir de entonces, los hospitales y centros médicos norteamericanos deben entregar un reporte a la AAMI en el que consignen el seguimiento realizado a sus protocolos, con énfasis en las fallas detectadas a nivel de seguridad de los equipos, actualizaciones de software y generación de estrategias para control de daños.

Las guías invitan además a las autoridades sanitarias a evaluar consecuencias de la falla de un equipo biomédico, a construir entornos seguros para el almacenamiento de dispositivos y a regular los niveles de humedad y temperatura a los que éstos son expuestos.

Al respecto, Paul Kelley, Director de Ingeniería Biomédica de la Green Initiative and Asset Redeplyment del Hospital de Washington, concluyó: "en este trabajo participaron representantes de diferentes hospitales y clínicas, fabricantes, reguladores y organizaciones no gubernamentales, por lo que el producto final contiene diversos puntos de vista, que hacen más fácil su aplicación real en los centros de atención".

Para obtener un ejemplar de las guías puede visitar el siguiente enlace aquí.

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asociación para el avance en instrumentación médica

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guías de mantenimiento de equipos médicos

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centros para los servicios de medicare y medicaid de estados unidos

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AAMI publica guías para el mantenimiento de equipos médicos

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La Asociación para el Avance en Instrumentación Médica (AAMI, por sus siglas en inglés), publicó un documento que busca orientar sobre el mantenimiento de calidad a los equipos médicos, para lograr un funcionamiento eficiente de los mismos y garantizar la obtención de resultados confiables en los estudios realizados.

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(Comisión Electrotécnica Internacional) es la organización líder a nivel mundial para la preparación y publicación de normas internacionales para todas las tecnologías eléctricas, electrónicas y relacionadas

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Asociación Nacional de protección contra el fuego se ha dedicado a proteger vidas y bienes de los efectos devastadores de los incendios y otros peligros. A través de los Códigos Nacionales contra Incendios de la NFPA, desarrollo profesional, educación, programas de asistencia a la comunidad, e investigación, la NFPA continúa

siendo la asesora mundial en seguridad contra incendios, eléctrica y de edificación

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El Reglamento tiene por objeto establecer la condiciones técnicas y garantías que deben reunir las instalaciones eléctricas conectadas a una fuente de suministro en los límites de baja tensión.

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Es una norma para equipos electromédicos: Ensayos recurrentes y ensayos después de reparación del equipo electro médico.

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Es una familia de normas cuyo ámbito abarca la seguridad, el rendimiento esencial y la compatibilidad electromagnética de los equipos y sistemas eléctricos médicos.

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The third edition of IEC 60601-1 was published in December 2005, but few certification bodies (CB) certificates have actually been issued to this version of the standard and few agency mark projects have been completed around the world.1 There were five CB certificates issued in 2008 and 14 as of May 2009. Many manufacturers have asked safety agencies to conduct gap analysis comparing the second edition with the third edition requirements. Why is it taking so long to get this standard to be used for meeting regulatory requirements around the world? There are still challenges in determining the best approach to implement and use the standard, and there are several questions facing regulators and standards writers, including the following:

* How should the CB scheme issue certificates to the standard, taking the requirements of ISO 14971 into consideration?2

* Will test labs and national regulators be ready for the shift to the third edition, including the major aspects of essential performance and risk management?

* How is the transition period going to work for countries that issue national versions of 60601-based collateral and particular standards? The national versions need to be updated and published to align with the third edition of IEC 60601-1.

Answering these questions is a first step toward understanding the finer points of the standard and the path device makers should take. Medical device manufacturers should learn about the standard so that they can decide how to transition from the second to the third edition as smoothly as possible.

Looking Back and Looking Forward

The IEC 60601-1 standard, "Medical Electrical Equipment-Part 1: General Requirements for Safety," is the cornerstone document addressing many of the risks associated with electrical medical equipment. Ensuring that a device complies with IEC 60601 can be a complex, multifaceted task.

To better understand the standard, it helps to talk about its history. IEC and ISO standards development projects typically take 3-5 years. The third edition of IEC 60601-1 took more than 10 years of development before it was actually published. This unusually long development process was partially due to some significant changes to the standard. For example, the internal numbering system of the clauses has been totally redone, so that even those requirements that did not change require effort to find. To that end, a tool was developed, IEC/TR 62348:2006, which helps identify where certain second edition requirements are located in the third edition.3 This free document can be downloaded at the IEC Web store. Two errata sheets called corrigendum were issued.4,5 Also, two interpretation sheets (IS) clarified some of the requirements.6,7 The first says that the third edition does not apply to medical gas pipeline systems. The second clarifies that fire enclosure requirements of subclause 11.3 only apply when "...there is a significant likelihood of fire due to the presence of a source of ignition...and a significant source of fuel." In most cases, these requirements do not apply to the medical device under test unless the device is intended to operate in an environment containing flammable anesthesia. ⁸

Along with such documents, other work to align collateral standards (i.e., IEC 60601-1-XX) included updating the alarms standard IEC 60601-1-8 to the third edition. Most collateral standards were published based on second edition of IEC 60601-1. Alignment of the collaterals was completed in 2009. And, although not all of the particular standards (i.e., IEC 60601-2-XX) have been aligned with the third edition, it is hoped that the project will be completed by the end of 2009 as well. Any future dates mentioned in this article are estimates based on the most current information available.

The second edition of IEC/TR 62354, which details the testing procedures of medical electrical equipment based on third edition of IEC 60601-1, should hopefully be published by the first half of 2010.9 This technical report (a guidance, not a standard) primarily covers the third edition of IEC 60601-1. But it also covers the second edition where appropriate, since many of the test requirements from second edition carry over to the third. IEC/TR 62354 is designed to provide details on how to conduct the tests in 60601-1. The second edition of this guidance document will address the third edition of IEC 60601-1, which was not covered in the original version.

Going further into the future, the Amendment 1 (A1) to IEC 60601-1 is estimated to be published by June 2012. More than 150 comments have been collected during the last seven years in anticipation of adding corrections and modifications based on the experience of using this current version. These comments also include changes that didn't get into the published third edition of 60601-1. It is anticipated that a small portion of the particular standards may need to be aligned with IEC 60601-1 + A1 and that those efforts should be completed in 2015.

The CB scheme was originally established to facilitate the acceptance of test data (primarily electrical and mechanical) amongst member laboratories. Therefore, issuing certificates to IEC 60601-1:2005 related to the requirements of ISO 14971 represents a challenge. As documented on the IEC System for Conformity Testing and Certification of Electrotechnical Equipment and Components (IECEE; CB scheme) Web site, "....an international scheme is operated by the IECEE...based on the principle of mutual recognition...by its members of test results for obtaining certification or approval...."

However, IEC 60601-1 represents a departure from the traditional standards historically addressed by the CB scheme in that it involves more than electrical and mechanical testing. The third edition encompasses aspects never before considered, such as risk management, biocompatibility, and usability. Consequently, the CB scheme must develop an entirely new infrastructure to support methods for member laboratories to countercheck practices and procedures for certifying against new requirements.

When the CB scheme first approached the topic of risk management, it had to consider how the requirements of ISO 14971 should be evaluated. The two options are a desk review of a manufacturer's documentation or an on-site assessment of a manufacturer's risk management process.

To conduct an on-site assessment of risk management requirements per 60601-1, 3rd ed., all the safety agencies that issue a certification mark or CB certificate must employ trained ISO 14971 auditors. They must also have personnel experienced in the risk management process for ISO 14971, and biomedical experts that understand the necessary types of medical electrical equipment.

Recognizing such training as a significant challenge, the CB scheme conducted a workshop in October 2007 to train member test laboratories on the application of the risk management requirements. However, during this meeting, it became clear that divergent opinions existed, thereby frustrating hopes for a uniform acceptance of test reports generated by member laboratories.

Such challenges prompted the CB scheme to establish a Risk Management Task Force (RMTF) to set up a system for IEC 60601-1 to address the risk management questions. During the RMTF meetings, attendees discussed the need for training on risk management for safety agencies and the content of a new test report form (TRF).

A third edition TRF is published and has been in use for several years now. This TRF contains some of the risk management requirements but is set up more for desktop assessment of risk management than for on-site assessment. Further, the TRF does not provide sufficient detail on the content of elements that would normally be covered by a qualified auditor evaluating a given risk management process. To establish full compliance, the complete set of risk management process elements are required.

To establish uniformity of member test laboratories in ISO 14971 requirements, the RMTF has spent considerable time detailing the needed elements when "inspection of the risk management file" is called out in IEC 60601-1. Based on this work, it is anticipated that the TRF will be modified before A1 is published.

Several IEC committees are discussing the difficulty of desktop risk analysis. These groups (collectively, IEC TC 62/SC 62A-D) include the technical committee for electrical equipment in medical practice; the subcommittee for common aspects of electrical equipment used in medical practice; the subcommittee for diagnostic imaging equipment; the subcommittee for equipment for radiotherapy, nuclear medicine, and radiation dosimetry; and the subcommittee for electromedical equipment.

Once A1 is published, it is anticipated that certifying agencies will be required to do an on-site assessment of the manufacturer's whole risk management system.

The second challenge is getting test labs and national regulators up to speed on the paradigm shift to the third edition. Both essential performance and risk management are new concepts for the IEC 60601 series of standards, and thus it has taken time for the labs and regulators to understand the processes. At this point most of the test labs have a pretty good understanding of the term essential performance because they tend to be involved in the standards development process.

Risk management is not a new concept for the national regulatory bodies of the medical industry. However, it is new for some of the safety test labs unless they happen to be a notified body for the Medical Devices Directive (MDD) or are auditors for national regulatory systems, which require ISO 14971 knowledge. Otherwise, risk management requirements are a game changer when added to the medical electrical product safety standard.

As mentioned previously, the CB scheme system is not set up for on-site assessments of risk management and TRFs are not structures for full risk management assessment. Some of the safety test agencies also were not set up to meet the challenges because their engineers are skilled at testing and certifying, not auditing.

In addition to these two problems, there is the new collateral requirement which, per the third edition, says that "any applicable collateral standard becomes normative at the date of its publication." This means that any published collateral standard in the IEC 60601 series needs to be used in conjunction with third edition to meet the overall standard. The collateral requirement complicates the CB scheme's plans because the group has not always issued certificates for collaterals in effect at the time of the certificate issuance.

Also, the MDD list of harmonized standards has all of the collateral standards for third edition published except for EN 60601-1-9, which is the standard for environmentally conscious design of electrical medical devices.10 Protecting the environment is not in the essential requirements of the MDD. Reviews to determine whether 60601-1-9 addresses the EU Energy Reduction Directive are in process. All of these elements add to the conflict, which makes sorting out requirements difficult for manufacturers.

The third question raised at the beginning of this article regards the transition period of adoption and how it will work for each country's regulatory framework. It is critical to discuss the timetable because the collateral and particular standards need to be updated and published so that they align with third edition of IEC 60601-1.

United States. In the United States, the national version of third edition is ANSI/AAMI ES 60601-1:2005, released in February 2006. Note that UL 60601-1, which is the national version to second edition, is still in effect. FDA has been working on a guidance document to use the third edition for several years, and it is hoped that the guidance will be released by the end of 2009. The guidance document should explain FDA's perspective on the use of risk management to get a product authorized to market and also discuss the structure of the third edition. Currently, the second edition of IEC 60601-1 is the recognized consensus standard on FDA's Web site and is used during the evaluation of a premarket submission for medical devices. There is no reference to the third edition of IEC 60601-1 or to the AAMI ES 60601-1 standard on FDA's Web site.

At this point, FDA has not specified when it will add either the third edition of IEC 60601-1 or ANSI/AAMI ES 60601-1 as a recognized consensus standard. The authors' best guess is that the United States will align with Health Canada's requirements (outlined in the following section). Note that if a product is approved by FDA and there are no substantial changes, as defined by FDA, then whatever standards the manufacturer met to gain said approval are appropriate. There is no need to upgrade the product to newer FDA consensus standards as they are published.

To obtain a U.S. product safety agency-approved certification mark (e.g., UL, CSA, TÜV America, and ETL) on a product, the test lab needs to be approved under the Nationally Recognized Test Lab (NRTL) program of OSHA for the appropriate standard. Currently OSHA deems the appropriate electrical medical standard under the NRTL program to be UL 60601-1, and not AAMI ES 60601-1. OSHA is in the process of reviewing the standard and determining the approach and schedule for using AAMI ES 60601-1 as the appropriate standard per NRTL.

It is also important to note that NFPA 99, the standard for healthcare facilities, is being updated to align with the third edition of IEC 60601-1 and it will hopefully be published in 2011. On June 11, 2009, the document was voted to be returned to committee at 2009's technical committee meeting and won't be reintroduced for a vote until 2010. Once the document is approved, the third edition should trickle down into the local U.S. fire codes fairly quickly.

Canada. After the third edition was published, Canada adopted a policy that seemed too early for manufacturers to meet. It required that a manufacturer needing a Health Canada certificate for a new product or for a reissuance of a certificate provide proof that it met the third editions of both IEC 60601-1 and IEC 60601-1-2.11 The drop-dead date for manufacturers to comply was December 15, 2008. Industry and the standards development community pushed back saying that the mandatory compliance date was unreasonable, and Health Canada backed off the requirement in October 2008. For now, companies have some options. Until May 31, 2012, a manufacturer can obtain a certificate using the second edition of IEC 60601-1 as well as the applicable collateral and particular standards. Alternatively, if they feel compelled, they can obtain a certificate by proving compliance with the third edition of IEC 60601-1, along with the applicable collateral and particular standards. After the May 2012 deadline, however, companies will be obligated to use the third edition requirements without exception to obtain a Health Canada certificate.

On June 1, 2012, it will be mandatory to comply with the third edition of IEC 60601-1 and the applicable particular and collateral standards for new product submissions to Health Canada. Any new product that is certified by Health Canada prior to June 1, 2012, will not need to meet the third edition unless there are substantial changes that would otherwise require a company to resubmit to Health Canada after May 31, 2012. The Canadian national version of the third edition is CAN/CSA-C22.2 No.60601-1:2008, issued July 31, 2008. The national deviations for this version are similar to the previous version CAN/CSA C22.2 No. 601.1-M90, which is the second edition equivalent national standard. At this time, there is no estimated transition period known for the withdrawal of CAN/CSA C22.2 No. 601.1-M90. Currently the Standards Council of Canada allow issuance of Canadian safety test lab agency marks to CAN/CSA C22.2 No. 601.1-M90 and CAN/CSA 60601-1:2008.

European Union. Previously, September 12, 2009, was the deadline for the MDD presumption of conformity for products that fall under EN 60601-1 to meet the third edition, which has no particular standards applicable. As of December 2008, both the second and third editions of EN 60601-1 and all the collaterals (related to both editions of EN 60601-1), other than EN 60601-1-9, are on the list of harmonized standards. Manufacturers can use either edition of EN 60601-1 and applicable collateral and particular standards to meet the presumption of conformity for the MDD.

On June 19, 2009 CENELEC TC 62 voted to change the date of withdrawl for EN 60601-1:1990 (second edition) to June 1, 2012. This vote was sent onto CENELEC Technical Board and should soon be sent to the EU Commission for ratification. This date lines up with the Health Canada date. Therefore, for any product that is CE marked under the MDD on or after June 1, 2012-even if CE marked based on the second edition-the product "placed on the market" or "put into service" (both MDD-defined terms) will need to meet the current list of harmonized standards as the standards are updated and published under the European Journal. In the EU, there is no national safety agency certification mark because the CE mark per the MDD is the only mark allowed.

Other Countries. Other countries are at various stages of getting their national versions of the standard ready for both regulatory and safety agency certification marks. Some of the countries that are working on their national editions of the standard include Brazil, Japan, and China.

Next Steps for Manufacturers

How does a manufacturer deal with all the conflicting requirements? Should they should use second or third editions to get their products approved for national regulatory regulations and safety agency certification marks? This second question brings to the forefront that companies must put together a company strategy to transition from second to third edition for its product lines. To do so, consider the following:

* Determine what countries a product will be sold and marketed in.

* Decide how long new and legacy products will be sold or distributed in the specific country of concern.

* Decide what certification agency marks are required on the products.

* Conduct gap analysis for second and third editions on product lines early in the design cycle to minimize potential nonconformities. A safety certification agency or a consultant with expertise in the 60601 series and national regulatory requirements can help.

* Talk with the company's safety certification agency to get the current understanding of the applicable requirements.

* Talk with a notified body (EU), a CMDCAS registrar, or other national regulatory agencies to get an understanding of the changing requirements for the applicable requirements related to IEC 60601-1.

Once such analysis is conducted, a manufacturer should have a solid basis for determining whether certification and national regulatory approval to the second edition, third edition, or both standards is best. For many companies, the strategy until 2012 continues to be to obtain certification to the second edition, but also plan for a third edition certification. Such decisions must be based on the design life of the product and market.

Leo Eisner is the head of Eisner Safety Consultants (Portland, OR). Garry Lee is president of Global Advantage (Richmond Hill, ON, Canada) and Mark Leimbeck is program manager, health sciences, at Underwriters Laboratories (Northbrook, IL).

1. IEC 60601-1:2005, "Medical Electrical Equipment-Part 1: General Requirements for Basic Safety and Essential Performance" (Brussels: International Electrotechnical Commission, 2005).

2. ISO 14971:2007, "Medical Devices-Application of Risk Management to Medical Devices" (Geneva: International Organization for Standardization, 2007).

3. IEC/TR 62348:2006, "Mapping Between the Clauses of the Third Edition of IEC 60601-1 and the 1988 Edition as Amended" (Brussels: IEC, 2006); available from Internet: www.iec.ch/webstore/freepubs/iec62348%7Bed1.0%7Db.pdf .

4. Corrigendum (Brussels: International Electrotechnical Commission, 2006); available from Internet: www.iec.ch/cgi-bin/getcorr.pl/iec60601-1-cor1%7Bed3.0%7Db.pdf?file=iec60601-1-cor1{ed3.0}b.pdf .

5. Corrigendum (Brussels: IEC, 2007); available from Internet: www.iec.ch/cgi-bin/getcorr.pl/iec60601-1-cor2%7Bed3.0%7Db.pdf?file=iec60601-1-cor2{ed3.0}b.pdf .

6. Interpretation Sheet 1 (Brussels: IEC, 2006); available from Internet: www.iec.ch/cgi-bin/getcorr.pl/iec60601-1-i1%7Bed3.0%7Db.pdf?file=iec60601-1-i1{ed3.0}b.pdf .

7. Interpretation Sheet 2 (Brussels: IEC, 2006); available from Internet: www.iec.ch/cgi-bin/getcorr.pl/iec60601-1-i2%7Bed3.0%7Db.pdf?file=iec60601-1-i2{ed3.0}b.pdf .

8. 62A/623/DC, "Proposal for an Interpretation Sheet for IEC 60601-1:2005"(Brussels: IEC, 2005).

9. 62A/647/DTR, "General Testing Procedures for Medical Electrical Equipment" (Brussels: IEC, 2009).

10. EN 60601-1-9:2008, "Medical Electrical Equipment-Part 1-9: General Requirements for Basic Safety and Essential Performance-Collateral Standard: Requirements for Environmentally Conscious Design" (Brussels; CENELEC, 2008).

11. IEC 60601-1-2, "Medical Electrical Equipment-Part 1-2: General Requirements for Basic Safety and Essential Performance-Collateral Standard: Electromagnetic Compatibility-Requirements and Tests" (Brussels: International Electrotechnical Commission, 2005).

Copyright ©2009 Medical Device & Diagnostic Industry

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Regulatory Strategies for the Third Edition of IEC 60601-1

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The third edition of IEC 60601-1 was published in December 2005, but few certification bodies (CB) certificates have actually been issued to this version of the standard and few agency mark projects have been completed around the world.1 There were five CB certificates issued in 2008 and 14 as of May 2009.

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Esta norma especifica los requisitos aplicables a los dispositivos de detección del aislamiento que permanentemente detectan la resistencia.

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Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. - Equipment for testing, measuring or monitoring of protective measures - Part 8: Insulation monitoring devices for IT systems

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Abstract

This part of IEC 61557 specifies the requirements for insulation monitoring devices (IMD) which permanently monitor the insulation resistance to earth of unearthed IT a.c. systems, for IT a.c. systems with galvanically connected d.c. circuits having nominal voltages up to 1 000 V a.c., as well as of unearthed IT d.c. systems with voltages up to 1 500 V d.c. independent from the method of measuring. This second edition cancels and replaces the first edition published in 1997. This edition constitutes a technical revision. The following changes were made with respect to the previous edition: a) definitions complemented; b) revision of some requirements; c) addition of information on operating instructions; d) sections "type tests" and "routine tests" complemented; e) modification of Table 1; f) addition of Annexes A and B. The contents of the corrigendum of May 2007 have been included in this copy.

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IEC 61557-8:2007 Standard | Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. - Equipment for testing, measuring or monitoring of protective measures - Part 8: Insulation monitoring devices for IT systems

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En los sistemas IT, todos los componentes activos están aislados de tierra o puestos a tierra mediante una impedancia elevada.

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¿Por qué el uso del sistema IT está tan poco extendido?

Hasta ahora, el sistema aislado de tierra se utilizaba sobre todo en aplicaciones críticas, como las unidades de cuidados intensivos o los sistemas de señalización ferroviaria, donde un fallo en el suministro de corriente puede tener consecuencias fatales. Fuera de estos ámbitos específicos, el esquema IT es poco utilizado, a pesar de que ofrece numerosas ventajas, no solo en cuanto a la seguridad, sino también en cuanto a la disponibilidad.
Existen tres mitos muy difundidos sobre los inconvenientes de este esquema de red:

El sistema IT es más caro que un sistema con puesta a tierra

En efecto, la instalación de un sistema aislado de tierra es más cara que una red TN o TT, pero las ventajas económicas que ofrece, como el mantenimiento preventivo y la reducción de las revisiones, compensan los costes adicionales en poco tiempo.

El sistema de TN permite hallar los fallos con mayor rapidez

Con el uso de sistemas de localización de fallos (IFLS, por sus siglas en inglés), también se pueden localizar rápidamente los fallos en el sistema IT.

Para el sistema IT deben adquirirse consumidores muy costosos

Con ayuda de medidas técnicas que no conllevan ningún coste adicional, también pueden utilizarse componentes estándar.

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Sistema IT: Sistemas aislados de tierra para máxima disponibilidad

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Hasta ahora, el sistema aislado de tierra se utilizaba sobre todo en aplicaciones críticas, como las unidades de cuidados intensivos o los sistemas de señalización ferroviaria, donde un fallo en el suministro de corriente puede tener consecuencias fatales.