Normen & Richtlijnen

The CE mark and the classification

All medical devices are subject to certain rules of classification. The actuators which we develop and produce for manufacturers of electrical medical equipment are hand and foot-controlled actuators which are classed as accessories under the German Medical Devices Act (MPG). As such, they are also subject to the Medical Devices Directive (93/42/EEC).

The EC directive for medical devices (93/42/EEC) distinguishes four classes (I, IIa, IIb, and III), referring to the risk potential of each product, whereby class I represents the lowest risk potential and class III the highest. Manufacturers are obliged to distinguish their products using these classes. Our actuators for electromedical devices have been classified accordingly.

The steute Meditec developers and product managers have long been paying careful attention to the standards and directives applicable to our products. How we need to proceed in this respect, which standards we have to observe and which developments in this fairly obscure field could emerge in the future, are summarised in the following pages.

All normative requirements fulfilled

Because the intended purpose of our switching devices – in combination with the downstreamed control unit of the system marketer – is to actuate medical devices, hence they count as accessories and have to be equipped with a CE conformity marking in accordance with the MDD.

All steute Meditec series fulfil the conditions stipulated by the directive for medical products (93/42/EEC), by the IEC 60601 series of standards and by the class of AP (anaesthesia proof). They also fulfil the criteria for protection classes up to IP X8 in accordance with IEC 60529.

Testing by a notified body

As a manufacturer of medical devices we also, in order to meet the high standards of quality and safety expected of medical equipment, subject our products to an additional and voluntary safety check by a competent testing authority (notified body).

This safety check comprises a prototype test of the product on the basis of harmonised European standards, a plausibility test for the conformity procedure which is necessary for the CE marking, including technical documentation in accordance with the EC directive, and an inspection of the factory with repeat production controls.

We document this additional voluntary safety check on our foot switches with the TÜV seal of approval »GM« (tested medical device).

The international valid standard IEC 60601

Which regulations exist for medical handheld and foot operated controls in Europe?

The EC directive for medical devices (MDD) or in Germany the MPG, appendix I, names fundamental requirements for medical devices: »Products must be designed and manufactured in a manner which ensures that … the safety of patients and users … is not put at risk.«

The solutions chosen by manufacturers during the design and manufacture of devices must obey the principles of integrated safety, not forgetting adherence to state-of-the-art technology.

»When choosing suitable solutions, manufacturers must apply the following principles, proceeding in the order set out below:

     
  1. Elimination or minimisation of risk (integration of safety concept in product development and construction).
  2.  
  3. Where appropriate, adoption of suitable protection measures, including alarms, to warn of non-eliminable dangers.
  4.  
  5. Instruction of users regarding residual risks for which no suitable protection measures can be found.«
  6.  

This three-step procedure has been tried and tested and is well established in other areas of safety engineering, e.g. machine safety.

The international level: IEC 60601

The IEC 60601 series of standards directs safety concepts for electrical medical equipment worldwide. IEC 60601-1 (medical electrical equipment) states (1st section 3.1): »In their normal state and on first error, devices … must not be hazardous … «.

The 2nd section 2.10.11 defines the criteria for a first error: »state when in the device a single protective measure has failed to prevent a hazard...«. 3rd section 52.1 »Devices must be constructed and manufactured in such a way that they are not hazardous on first error «.

The additional standards in series IEC 60601 describe the demands made of individual equipment classes (e.g.: IEC 60601-2-22 for laser devices and IEC 60601-2-43 for X-ray devices).

Functional safety

The third, revised edition of the IEC 60601series of standards, which appeared in 2006, accommodates the fact that medical devices are found increasingly frequently in integrated systems. Since then, this standard has covered the basic safety and functional safety of devices and systems. This means that the requirements of the additional standard IEC 60601-1-1 are now included within the basic standard.

The basic ideas behind the revised standard address two very important points: safety in use (usability) and risk management.

Risk management

Usability (IEC 60601-1-6): Minimisation of risks for patients and users

The new standard IEC 60601-1-6 refers to medical electric devices and their combinations. It describes the process of ergonomic design and gives instructions, as to how this process shall be organised, carried out and documented. The usability of the concerned medical equipment shall be so good that the fundamental safety, as well as its essential perfomance are secured. The standard refers explicitly to use errors and how these can be reduced to an acceptable value. Though the consequences of faults as result of the irresponsible conduct lie beyond the focus of the standard.

For many years now, steute Meditec has been adhering to the guiding principle of usability, as well as working closely with development partners and institutes with recognised expertise in the ergonomic comfort and usability of medical equipment.

Risk analysis / risk management for medical equipment

The idea of risk management known by the introduction of the ISO 14971 has characterised the basic concept of the third edition of IEC 60601-1. With it the product standard, as well as the process standard, are considered.

Basically the degree of risk is determined by two factors: degree of damage and possibilty of occurrence.

The risk analysis is in the meantime for designing engineers and safety engineers a usual method. The risk management per ISO 14971 and IEC 60601-1-1 goes beyond this. Beside the pure analysis and determination of risk classes, it contains decisions about the acceptability of the planned safety measurements, as well as the definition, implementation and verification of countermeasures and market observation.

Minimize risks for users, patients or others to an acceptable degree

Risk analysis and/or product standard?

The manufacturer, meticulous to details, might question whether a risk anylysis is obligatory in the case of an existing product standard. The answer is: In principle yes, because the product standards also aim to define the necessary measurements, in order to reduce the risk to an acceptable degree. But the standards are often not state-of the-art. Thus the manufacturer should verify if the current technology is still covered by the standard.

Moreover the product standards assume standard realisations. »Exotic« concepts are often not considered. In these cases the more basic EN 1441, describing the risk analysis, is a lot more helpful. Furthermore the product standards (partly implicitly) are based on the assumption that certain application fields and principles are present. Thus it must be verified if the product is covered by it. Finally the product standards do not consider the optional components. Therefore it should be checked if all functions or components of the product are covered by the standard.

Alignment with other areas of safety technology

The revisions made to the IEC 60601-1 standard need to be viewed in a wider context. In other safety-relevant areas, e.g. machine safety, terms and procedures such as functional safety, risk analysis, hazard assessment, etc. also constitute part of the state-of-the-art technology.

Different systems of standards are thus gradually becoming aligned. Since we are also one of the branch leaders for safety switchgear used in machine and plant engineering, as well as for safety switchgear used in explosive environments, steute is able to benefit from considerable synergies in this respect.

International harmonisation of standards

A further key trend in conjunction with the standards and directives for medical equipment is harmonisation at a European and international level. And even when EN or IEC rules and standards are not adopted 1:1, they still serve as the basis for various national standards. In the USA, for example, the product standard UL 60601 must be observed. It correlates closely with IEC 60601, while taking into account typically American realities. All standard series made by steute are checked for compliance by the CSA.