Introduction.pdf

Introduction

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Introduction

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Fire – Constant Hazard with Highest Hazard Potential.........................13 Purpose of the Fire Safety Guide ........................................................15

11 Fire Safety Guide / © Siemens Switzerland Ltd

Introduction

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Fire – Constant Hazard with Highest Hazard Potential Since the middle ages, when whole cities burnt down, mankind has learned a lot and has taken constant efforts to avoid and contain fires. These efforts, however, have been compensated by additional sources of ignition and increasing combustible loads. Today, virtually every household and every company features PCs, TV, halogen lamps, coffee machines and other electrical appliances, heating and air conditioning equipment, etc. Most of these devices include a power supply unit and other electronic modules, thus constituting potential sources of ignition. But fires may also be laid deliberately. The share of arson is already 25 to 40%, and figures are increasing1. Deliberately laid fires often spread quickly and fire fighting is extremely difficult. On average, such fires are three times as expensive as an average event of fire2. In our affluent society, buildings are furnished with more and more luxurious textiles, carpets, etc. In addition, the use of economic, easy-to-process and moldable die-cast synthetic material is permanently increasing. Apart from the increasing combustible load, these substances are mostly highly inflammable and react as fire accelerants. This effect is much more fatal than the mere combustible load would reveal. A conflagration releases approximately as much power as a nuclear power plant – such conflagrations may reach several hundred MW to some GW. A limited paper fire during which 3g of paper are burned per second already generates 40kW and a flame height of 0.8m. In addition to heat, each fire, whether large or small, produces toxic waste and highly toxic smoke gases. These gases contain, among other substances, carbon monoxide, hydrochloric acid gas, chloric gas, various sulfur compounds, nitrogen oxides (NOx), hydrocyanic acid gas and many other highly toxic substances, even phosgene. The loss of human life and financial damage caused either directly or indirectly by smoke gases is accordingly high. All over Europe, more than 4'000 people die every year because of fire events3 – most of them from smoke poisoning. It is difficult to assess the number of injured persons even approximately – it might amount to ten times as many seriously injured and hundred times as many slightly injured persons. Altogether, this amounts to approximately half a million people who fall victim to fires every year, and who partly suffer permanent damage.

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Introduction

The expenditures for direct fire-related damage in Europe amount to 1 to 3 tenth of a percent of the GNP4. This means that the direct damage caused by fires in Western Europe amounts to more than 15 billion €5. The indirect consequential damage may be ten times higher. In comparison: The upper limit of expenses of the EU-25 household for 2005 is approximately 120 billion €. Examinations have shown that the largest part of this enormous damage is caused by smoke gases and their corrosive constituents. Damage caused by smoke is approximately ten to hundred times higher than the actual fire damage6. Approximately one third of this smoke damage can be traced back to hydrochloric acid (HCl) released by fire, which results in corrosion of installations and devices. For an individual company this may be fatal. According to estimations by experts7, a conflagration in a company’s premises may have the following, disastrous effects: • For approximately one third of the companies concerned, direct fire damages result in bankruptcy. • For another third of the companies concerned, the loss of their customer base results in bankruptcy within three years. • The residual third often has to merge with other companies or needs to be sold. Sometimes, however, the company has the force to survive. Damage caused by fire shows that fire prevention, fire detection and fire fighting are highly up-to-date topics we have to face.

14 Fire Safety Guide / © Siemens Switzerland Ltd

Introduction

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Purpose of the Fire Safety Guide It is the goal of fire protection to effectively save people, material goods and the environment from the dangers and effects of fire. In addition, material damage resulting from operational interruption or the loss of the customer base shall be minimized. Good fire protection is based on the relevant, harmonized structural, technical and organizational fire protection measures. In contrast to many other investments, fire protection aims at preventing events. Success is thus mostly not visible – only failure becomes visible in the form of major fire events. Practice has shown that the investment in a well conceived fire protection concept is not normally higher than the investment in a suboptimal concept. Good fire protection is thus not a short-term investment but an economically motivated way of thinking. For many years, Siemens has been and still is a committed, worldwide active provider of detection, evacuation and extinguishing systems as well as danger management systems. It is our concern to provide an overview of the most important topics in technical fire protection and showing the most significant correlations with this Fire Safety Guide. The Fire Safety Guide supports you in evaluating fire protection systems, so that you may have the highest possible benefits from your choice of fire protection solution. To guarantee sufficient safety from fires, national and regional directives have been laid down in most countries. Personal safety is generally regulated by laws and official requirements. Protection of material assets is mainly a matter of insurance companies that have laid down corresponding guidelines and directives. Such claims and requirements in laws, rules, directives and standards unambiguously take priority over the recommendations in this Fire Safety Guide and must be taken into account in planning your fire protection solution. If fire protection measures are not called for, fire protection matters are the responsibility of the fire detection system planners. Siemens and the former Cerberus have conducted basic research for many decades and have worked out many documents on fire protection. Most of them have been made available for internal use only. This Fire Safety Guide is based on these documents and on the extensive knowledge and experience of Siemens and the former Cerberus. References appear only where they refer to documents that have been made publicly available.

15 Fire Safety Guide / © Siemens Switzerland Ltd