RockDelta stone wool means advanced fire protection. RockDelta stone wool is made from diabase rock and therefore cannot burn. Without the use of environmentally harmful flame inhibitors, RockDelta stone wool inherently resists temperatures higher than 1000°C. Demanding fire protection applications, e.g. within maritime and off-shore engineering, accordingly rely on stone wool to act as an effective fire barrier which controls the spread of the fire and provides valuable extra minutes to save people, property and reduce the environmental damage.
Tunnel Tracks and Fire Safety: A Vitally Important Topic
Fire safety is a vitally important topic with special consequences related not least to tunnel tracks. Accordingly, for every building component in the tunnel structure, accurate knowledge of the components resistance to fire and reaction to fire – including, for instance, toxic smoke generation – is of the utmost importance. Several major fires in European road and rail tunnels over the last decade have spurred a massive increase in the focus on tunnel fire safety, evidenced for instance by the large-scale seven multi-national projects that was funded under EU’s 5th Framework Programme on Tunnel Fireand Safety.
EU Fire Safety Classification System
A new EU fire classification system replaced old national systems by the year 2001. This affected all decision-makers in the building industry and all building users – and provided for a modern, elaborate and precise means of determining whether a material fuels a fire or provides resistance to the fire.
This new fire classification system consists of seven categories as follows: A1, A2, B, C, D, E and F. RockDelta stone wool based track anti-vibration mats do not only exhibit exceptional functional performance under even the most extreme climatic conditions, but also, stone wool comes with inherent and unique fire safety features as evidenced by the fact that all RockDelta stone wool based products fall into Euroclass A2 which means that the material is non-flammable, non-combustible and exhibits no flashover, no flaming droplets (d0) and minimum smoke emission (s1) during a fire. RockDelta stone wool thus helps to ensure an effective fire safety with enhanced protection against loss of life, structural damage and financial losses.
EU Fire Safety: Towards Harmonization in the Second Half of the 20th Century
In the second half of the 20th century, almost every country in Europe developed their own national system for fire testing and classification of building materials. More than 35 different national standards were used, confusing consumers and producers alike. Furthermore, some standards were even conflicting as one material could be classified as hazardous in one country and safe in another country.
In the early 1990´s The European Commission therefore decided to harmonize the standards for testing and classification of all building materials intended for sale in the EU. Two sets of standards were drafted under CEN (European Committee for Standardization): one for reaction to fire of materials and one for fire resistance of construction elements.
Until the year 2001, across Europe national standards on reaction to fire were employed. These national standards were typically developed more than fifty years ago at a time when building materials were mainly wood, glass, stone and cement. They were clearly not meant for testing the large variety of sophisticated and complex building materials used in the modern day constructions. CEN accordingly developed a new set of standards better suited at evaluating today's suite of more complex building materials.
Reaction to Fire and the New Euroclasses
Based upon an elaborate test scheme, all building materials (except flooring and roofing materials) are ranked in one of seven new Euroclasses that reflect the material’s reaction to fire. The purpose of this reaction to fire testing is to determine whether or not material fuels a fire.
The reaction to fire tests crucial properties of the building material in question and use the results of these tests as evaluation criteria for the classification. The classification result is furthermore based upon a combination of properties tested.
The classification is based upon two standards: EN 13823 - Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item (SBI) and EN 13501-1 - Fire classification of construction products and building elements - Part 1:
Classification using test data from reaction to fire tests. Following these two standards, the properties to be tested are as follows:
- Spread of fire
- Ignitability
- Rate of heat release
- Rate of spread of flame
- Toxic gases
- Smoke generation
- Flaming droplets
These properties are measured with a system of four harmonized, small-scale test methods plus an elaborate large-scale reference test protocol.
The seven Euroclasses are as follows:
A2 No contribution to a fire, non-combustible, no flash-over, additional classification for smoke production and droplets
B Very limited contribution to a fire, no flash-over
C Limited, but some contribution to a fire, flash-over risk
D Not negligible contribution to a fire, flash-over risk
E Poor fire reaction properties, flash-over risk
F No performance determined, no data available, flash-over risk
The A2 (s1, d0) classification clearly demonstrates that RockDelta stone wool based track anti-vibration solutions exhibit outstanding fire safety features which has enabled modern day track engineers to achieve a level of tunnel fire safety hitherto unattainable with traditional materials for track anti-vibration treatments of which several have been known to fuel a fire (and generate toxic smoke) rather than helping to prevent the fire from developing.
Several major fires in European road and rail tunnels over the last decade have spurred a massive increase in the focus on tunnel fire safety, evidenced for instance by the seven multinational projects that were funded under EU´s 5th Framework Programme on Tunnel Fire and Safety. A key safety parameter remains smoke generation, which relates directly to human safety under a fire and therefore is a vitally important characteristic of any building material. RockDelta stone wool based anti-vibration mats are all classified as s1 (best class, i.e. minimum smoke production) whereas for example Polyurethane (PUR) based materials, normally emitting dense and highly toxic smoke, are generally classified as s3.
Comprehensive information related to stone wool and fire safety can be found here. Furthermore, the RockDelta TechNote, entitled “Advanced Fire Protection with RockDelta Stone Wool: CEN Classification of RockXolid® and RockBallast®“ also gives a comprehensive look at the fire and smoke safety aspects of RockDelta stone wool relative to the new Euroclasses.
Flaming particles or droplets can cause further spread of fire. Building materials in Euroclasses A2 to D that give off no burning droplets within the first 600 seconds, are classified as d0. If droplets are generated and burn for less than 10 seconds the material will be classified as d1. If droplets are generated and burn for more than 10 seconds, the material will be classified as d2. RockDelta® stone wool based anti-vibration mats are all classified as d0.
