The Third Certainty

Introduction

The route to compliance

Table 1 - the CE mark

The CE mark is applied to products (and/or their packing and instructions) to show that the manufacturer, agent or importer can demonstrate compliance with all relevant directives. The requirement to demonstrate compliance may have involved a third party (as with the medical devices directive or parts of the Machinery Safety or EMC directives) or be based upon self-declaration, commonly backed up by third party testing, within a supporting technical file (as with the Low Voltage directive). Applying the mark means that all requirements have been satisfied, including completion of a declaration of conformity. However, the regime for compliance varies between directives and hence the CE mark has many meanings. The CE mark allows free and unhindered transport throughout the EU. It is effectively a free trade mark. The CE mark is not a mark of quality or safety. It does not mean that the product on which it is placed is either good or safe. It is a statement that the person applying the marks believes that they have satisfied their legal obligations. The CE mark is not a purchasing mark nor (for most directives) is it a mark of approval or certification. There is no guarantee attached to the CE mark. It is not equivalent to a third party approval mark such as those provided by FIMKO, VDE, etc.

There are at least six CE directives which may apply to electrical products. The most common are Low Voltage (LVD), Electromagnetic Compatibility Directive (EMC), Machinery Safety (MSD), Medical Devices (MDD), Gas Appliances (GAD) and Radio and Telecommunications Terminal Equipment (R&TTE). In addition you may need to consider non-CE marking directives for Explosive Atmospheres, General Product Safety or Product Liability.

The establishment of what directives apply is most important since some of the inter-relationships are quite complex. The 1997 guidance notes on the Low Voltage Directive (issued by the Commission) detail some of the relationships that effect application of the Low Voltage Directive, e.g. the Machinery Safety Directive and the Low Voltage Directive are applied in a complimentary fashion (predominance is often given to the former since it includes compliance with the Low Voltage Directive from within its own Essential Health and Safety Requirements (under its clause 1.5.1)).
 

Table 2 - UK legal obligations

Regulation 5 of SI3260:1994 requires electrical equipment to satisfy three measures. The first of these is to be "safe", the second is to manufactured in accordance with good engineering practice (i.e use of a harmonised standard) and thirdly to satisfy the safety objectives (as in Annex I of the Low Voltage Directive). The definition of "safe" is derived from Section 19 of the Consumer Protection Act 1987 which contains the meaning of "no risk, or no risk apart from one reduced to minimum, that the goods, their use or assembly, whether immediately of after time, will cause the death of, or any injury to, any person". The Regulations extend the coverage to domestic animals and damage to property.

Standards contain the detailed requirements for testing and assessing products. They can be used to demonstrate compliance with the principal safety objectives of the Low Voltage Directive. Standards are not the law and are the Aservants@ of directives. The test and assessment methods they contain provide a route path through the essential features of a safety assessment and give tangible parameters against which a product can be evaluated. There are 500+ harmonised standards for electrical safety. Standards cover domestic, commercial and industrial environments. They cover whole equipment as well as the components used within them. There is a hierarchy of standards stated within the Low Voltage Directive. EN standards should be used in preference to IEC standards that shall in turn be used in preference to national standards (e.g. BS or DIN VDE). National standards may be used but are generally only useful in the country of issue (e.g. BS in the UK).

Ostensibly, harmonised (EN) standards provide a presumption of conformity with the essential requirements of the Low Voltage Directive. However, it is worth noting that many of the EN standards published by BSI in the UK contain the statement "Compliance with a harmonized standard does not of itself confer immunity from your legal obligations." This statement should alert us to the requirements of Article 9 of the Low Voltage Directive that allows for failures or shortcomings of standards in respect of some of the objectives of Annex 1 of the Low Voltage Directive. There are many examples including that exclude the elderly and infirm from the scope (and thereby protection) of some domestic appliance standards (e.g,. waste disposers) and others that exclude service personnel from the protection requirements (e.g. EN 61010-1 - laboratory, measurement and process control equipment).

Although there is no mandatory requirement to apply standards, it is expected that most manufacturers will use them to demonstrate compliance. It is worth noting that it is accepted practice across the EU to use standards as the basis for enforcement action. However, whether standards are used or not, directives such as the Low Voltage Directive have a mandatory requirement for a test report in the technical documentation.

The choice of which standard to apply depends on the product type and the directives against which it is being assessed. You should also ensure as part of your assessment process that the principal safety objectives have been adequately covered by your chosen test standard.

Some key Low Voltage Directive product standards are:

Examples of typical product types and the most applicable standards
Product type	Applicable standard
Domestic electrical products (also products for commercial use in environments similar to the home or where products will be used by the public) e.g. Washing machines, vacuum cleaners, commercial catering equipment, vending and amusement machines	EN60335-1:1994 and any one of 100+ part 2 standards (e.g. EN60335-2-29 for battery chargers).
Domestic electronic products (also professional audio-visual equipment) e.g. Television sets, video recorders, hi-fi systems	EN60065:1998
Information technology and business equipment (including office and data processing equipment) e.g. Computers, photocopiers, fax machines.	EN60950:1992 (soon to be updated to EN60950:2000)
Luminaires (including domestic and commercial lighting) e.g. Table lamps, street lighting	EN60598-1:1997 and any one of 20+ part 2 standards
Laboratory, measurement and process control equipment e.g. Multimeters, oscilloscopes, temperature or flow monitoring equipment.	EN61010-1:1993 and in some cases one of the small number of part 2 standards
Industrial machines	EN60204-1:1998 and EN60439-1:1994 (although neither provide comprehensive coverage of the Principal safety objectives in their own right and usually require cross reference to other standards)

Selecting directives and standards

The key to this methodology is the Aproduct@ apex (which can also form the hub of a network of triangles where more than one directive applies). The term Aproduct@ is in this case defined by the type of product, its application, environment and conditions of use.

Use of the principal safety objectives

Where multiple or part standards are involved there is increased emphasis on the use of the principal safety objectives (Table 3 refers) to demonstrate compliance. As I have highlighted earlier, these objectives have predominance over standards and there are common examples of standards not necessarily covering all of the issues with a given example of product type. For all products within its scope, the obligation to comply with the Low Voltage Directive means compliance with these principal safety objectives (probably using an EN standard as the foundation for your declaration).

Table 3 - Summary of the principal safety objectives (Low Voltage Directive Annex I)

General conditions Marking and instructions necessary for safe use Manufacturer's name or brand marking Use of suitable components, materials and assembly techniques to ensure that the equipment can be safely connected. Design must ensure compliance with provisions for protection against hazards internal and external to the equipment Protection against hazards arising from the electrical equipment Protection from hazards due to direct or indirect electrical contact Temperatures, arcs or radiation which could cause a hazard must not be produced Protection from non-electrical hazards Electrical insulation is suitable for foreseeable conditions Protection against hazards which may be caused by external influences Mechanical elements of the design must ensure safety - mechanical strength and impact resistance Non-mechanical influences such as heat (deformation) must not effect safety In foreseeable conditions of overload the equipment shall remain safe

The principal safety objectives are included within the "design brief" of all standards intended for use with the Low Voltage Directive. In some of these standards there is an explicit statement of design principles to prevent hazards. These design principles can be related to the principal safety objectives of the Low Voltage Directive.
 

For example in EN60065 and EN60950 this is expressed as a series of hazards:

Hazard	Related objective
Electric shock	Objective 2a and 2d
Energy hazard	Objective 2a and 2b
Fire	Objectives 2b and 3c
Mechanical and heat hazards	Objective 2b, 2c and 3c
Radiation hazards	Objective 2b
Chemical hazards	Objective 2c

These hazard prevention principles relate to the main body of the standards where the specific test and assessment procedures are contained. The remaining objectives are addressed within these procedures.

For example:

EN60950 clause 1.7	Objective 1a and 1b
EN60065 clause 14	Objective 1c

It is unusual for a single clause within a standard to directly address a particular principle objective. It is more common for the objective to be satisfied by a combination of clauses. This is why such emphasis is placed upon using the whole standard for an assessment rather than selecting "appropriate" parts. It is logical that a standard is as incomplete and as useless as any other book where chapters have been selected out of sequence or omitted altogether.

Conclusion

Simon Barrowcliff is a director of the safety division of TRL Compliance Services Ltd. TRL Compliance Services Ltd is a notified body under the R&TTE and Low Voltage directives and a competent body under the EMC directive. Tel: 01695 556666. Email: simon@trllvd.co.uk. URL: http://www.trlcompliance.com.