WCA January 2016

Fire Risk and Safety Philosophy in Indoor Cabling By Jörg Bör

Abstract The fire performance of cables is a very important issue, especially in indoor cabling. On the one hand cables must not ignite by their own in case of any perturbance. But in most cases cables connect different rooms or devices with each other. Thus on the other hand fire propagation is no less important than self-ignition. Thirdly, fire ratings are defined for safety relevant applications. IEC 60331 specifies a period of time during which the intended performance has to be maintained while a permanent flame is burning the cable. Although this knowledge is common, experts often wonder why fire performance requirements seem to be weak in some regions. But the understanding of the specific fire safety philosophy leads to understanding the different approaches to achieve fire safety in different countries. Every risk is defined as the product of two factors: one is the probability of an accident and the other is the extent of damage. The risk is quantified by multiplication of these factors. This is the same for the risk of fire. In some countries fire safety philosophy focuses exclusively on the avoidance of any fire. So the target is to reduce the probability of fire close to zero. In other regions both factors of risk are considered. Thus the burning characteristics are much more important. If a fire appears, negative effects on the health of persons or technical goods shall be as low as possible. This includes the aspects of corrosive fumes, which may transform to acids by reaction with any water, as well as the reduction of smoke density, which might cause bad sight in case of fire and confuse any people looking for emergency exits. For this reason, the criteria “halogen free” and “low smoke” are much more important in Europe than, for example, in America. Halogens there are used especially for fire avoidance, because these elements have self-extinguishing effects. The highly reactive elements of the 7 th principal group collect oxygen and help to stop a fire. But compounds of halogens with oxygen are acid radicals, which react with the omnipresent water and turn into an acid. These corrosive smokes are a danger for personal health and might damage technical goods as well. This paper discusses the different approaches of fire safety, threats and advantages.

1 Introduction American experts often ask why European countries have weak fire protection regulations. On the other hand European people wonder why Americans are not aware of the tremendous danger of acid smoke caused by halogen fumes. This difference is often discussed between experts in standardisation committees as well as with customers in cable sales presentations. Looking at European fire safety regulations, for example the “Constructive Products Regulation” (CPR) [6] , may be confusing. Why don’t European governments protect their inhabitants better against the risk of fire? Looking at American fire safety regulations does not confuse less: Why don’t American governments protect their people against the risk of acid fumes? In a democratic world, laws and regulations are not given to the people, but are made by the people. Laws and regulations are a result of the general public opinion and mentality. In a business market it should not only ask for standards and regulations but for the ideas behind them. Neither customs nor any other trade barriers prevent the sales of American products in Europe and vice versa, but the missing acceptance of those products by the final consumer. 2 Intercultural Differences The first step of knowledge of intercultural understanding is the experience that there are differences. The second step is to recognise that these differences cannot be evaluated to be better or worse, but just different. The reasons for intercultural differences cannot be investigated in this paper. Intercultural differences are often established by historic experience or by the influence of the geographic situation. Deeper explanations are given in the appropriate literature. One might think this might be an issue for typical consumer markets (B2C) but not in markets of industrial goods (B2B). But be aware, the managers in the B2B market are often women or men born in that specific region and living there, and they have to take into account the requirements of their selling markets which are usually in the same region. Hofstede [1] names this “cultural relativity”.

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Wire & Cable ASIA – January/February 2016