This shift was politically initiated by environmental concerns but is presently strongly driven by the market forces. Another reason for this focus is the difference between Europe and the US in the use of flame retardants, raising questions concerning the relevance in present fire safety standards. In all, this has caused a debate about how to ensure fire safety without compromising environmental and health quality.
The International Project on Flame Retardancy in Electronics1, which was carried out by IVF from 1997 till 1999, showed that fire safety is primarily achieved by the addition of flame retardants (the "chemical approach") and that there is a lack in knowledge of fire safety among designers. The use of materials that exhibit acceptable fire performance in a small scale test (UL94) seems to be a "default measure" for fire safety among many designers.
There are today several reasons for revisiting fire safety in electronic and electrical products and systems. These include:
- New legislation, including the emerging EU directives requiring a phase-out of certain flame retardants.
- Environmental demands focussed on the uncertainty of environmental properties of alternatives to traditional flame retardants.
- Continued miniaturization of electronics which may imply high power density and areas with excessive heat.
- The fact that fires occur despite the use of high fire performance materials.
An increasing dependence in society on reliable electronic systems, e.g. for telecommunication, banking, air control and e-commerce.
- The increasing use of polymers in E&E products, and
Anticipation that products with improved fire safety performance will offer added competitive edge on future markets.
Today's approach to fire safety is based on principles and test methods which were developed at least half a century ago, i.e., the use of a small scale test method, UL 94, which defines the fire performance of the test material based on the test configuration (vertical or horizontal) of a small sample (approximately 12 mm x 125 mm), and whether or not the material is self-extinguishing.
Fires cost 100's of millions of kronor each year in Sweden alone. In the whole EU it is estimated that approximately 5000 people die each year as a direct result of fires, to a cost of at least 0,65% of the GDP. Electrical fires are thought to be responsible for approximately 20% of this total cost. There can, therefore, be no doubt of the importance of preventing fires and in particular electrical fires. Figure 1 illustrates, for example, the increase in TV fires in Sweden in the early 90's. What can be difficult is to determine the most significant risk factors. This corresponds to where one should focus safety activities in order to obtain the greatest cost/benefit ratio.
While many sources of fires exist it is clear that electrical appliances constitute an important origin of domestic fires. In all it is anticipated that there is much to gain in commercial terms by a higher ambition for fire safety, while simultaneously including environmental and health concerns, both in the public and private sectors.
The objectives of this study have been:
To create a picture of the international state-of-the-art re design for fire safety.
To carry out a preliminary comparative test of the UL94 and cone calorimeter method for characterising flammability properties of materials, and
To identify areas for future research.
Figure 1: Increase in TV fires in Sweden during the 90’s.
Our experiences from fire tests, analyses of fire statistics, discussions with a large number of companies, and literature studies indicate that there is a clear need for a new approach to fire safety in E&E products and systems. The basic components in this new approach would be
- Performance based design
- Detailed characterization of flammability properties of materials
More information about the results of this study are available in the report; “FIRESEL: Fire safety in electronic and electrical products and systems - State of the art and proposal for a new approach2. A Workshop is planned for the first quarter 2003 to discuss these issues and plan future research in this field. More information will be posted as it becomes available.
- Bergendahl, C G et al: ”Alternatives to halogenated flame retardants in electronic and electrical products. Results from a conceptual study”. IVF Research Publication 99824, IVF Industrial Research and Development Corporation, 1999.
Andersson, D; Axelsson, J; Bergendahl, C G; Simonson M: “FIRESEL: Fire safety in electronic and electrical products and systems - State of the art and proposal for a new approach”. IVF Research Publication 01812, IVF Industrial Research and Development Corporation, 2001.