Birgit Östman

• Senior Researcher at Linnaeus University

This chapter deals with the fire properties and performance of wood products and structures. It starts with two subchapters on the basic physical and chemical properties under fire conditions including fire-retardant treatments to obtain higher reaction to fire classes. A new European standard to evaluate their long-term fire performance is include...

Acceptance criteria for products according to the cone calorimeter Birgit Östman, Linnaeus University, Sweden, Birgit.Ostman@lnu.se Short Communication DOI: 10.1002/fam.3119 The international standard ISO 5660 Cone Calorimeter test is widely used in fire research and for modeling, but not so often in legislation or requirements on products. The ava...

Wood and wood-based products are extensively used in the building sector due to their interesting combination of properties. Fire safety and fire spread, however, are of utmost concern for the protection of buildings. Therefore, in timber structures, wood must be treated with fire-retardant materials in order to improve its reaction to fire. This a...

This chapter covers control of workmanship, fire safety during construction, responsibilities and enforcement, fire detection and suppression and emergency procedures. Quality and inspection of workmanship are vital for high-quality buildings, whether of timber or other construction materials. Timber buildings require certain precautions due to the...

Link to the book Fire Safe Use of Wood in Buildings - Global Design Guide for Open Access digitalt and order of hardbound book: https://doi.org/10.1201/9781003190318

The possibilities for building in wood have gradually increased in recent decades mainly due to environmental benefits. But there are still restrictions in terms of fire regulations in many countries, especially for taller buildings. The situation has therefore been mapped in about 40 countries on four continents as an update to a survey in 2002. T...

Engineered wood products e.g. cross-laminated timber (CLT) and glued-laminated timber (glulam) are increasingly used as the material of choice for mid-rise to tall construction timber projects. However, the requirements to manufacture these timber elements are considerably different among countries and, consequently, do have an influence on their f...

The fire safety design of cross-laminated timber (CLT or X-Lam) in Europe is governed by the Construction Products Regulation and its essential requirements, as for all other building products. These requirements are mandatory, to be used in all European countries. They include classification systems for reaction to fire of building products, fire...

Fire retardants may considerably improve the reaction to fire properties of wood products, but the long term durabi­lity needs to be addressed. Several long term studies of fire retardant treated (FRT) wood products over time are presented. They are performed according to a European system based on earlier Nordic and North American systems and incl...

An overview of the European requirements on fire safety in buildings is presented based on the construction products regulation and its essential requirements. These requirements are mandatory, to be used in all countries. They include classification systems for reaction to fire of building products, fire resistance of building elements and structu...

The combustibility of timber is one of the main reasons that many building regulations strictly limit the use of timber as a building material. Fire safety is an important contribution to feeling safe, and an important criterion for the choice of building materials. Historically, the combustibility aspect of wood has been a disadvantage for using t...

Recent architectural trends include the design and construction of increasingly tall buildings with structural components comprised of engineered wood referred to by names including; cross laminated timber (CLT), laminated veneer lumber (LVL), or glued laminated timber (Glulam). These buildings are cited for their advantages in sustainability resul...

Bristande brandteknisk funktion hos byggnadstekniska detaljlösningar är ofta en starkt bidragande orsak till brandspridning. Flera incidenter de senaste åren visar tydligt att byggsystem med hålrum kan ha stor inverkan på brandförloppet och medföra stora egendomsskador i alla typer av byggnader. Befintliga rekommendationer om att brandstopp måste i...

Several long term experimental studies on the maintained reaction to fire performance of fire retardant treated (FRT) wood products over time are presented. They are performed according to a European system based on earlier Nordic and North American systems and include accelerated ageing according to different procedures and natural weathering up t...

This paper briefly reviews the main fire scenarios for exterior façade claddings on multi-storey buildings, together with available full-scale test procedures and performance requirements in different countries. It is obvious that there is no international agreement or approach on how to evaluate the fire safety of façade claddings. Two series of f...

The low thermal conductivity and slow charring rate of wood products may protect underlying products from being heated and ignited. A literature survey shows that such fire protective behaviour of wood coverings has been verified by different methodologies in several countries in and outside Europe. A new European system with K classes for the fire...

https://www.ethz.ch/content/dam/ethz/special-interest/baug/ibk/costfp1404-dam/documents/151019-NW-Berlin-COST-FP1404-book-of-abstracts-WG123-Farbe.pdf

Two series of full scale fire tests of wooden facades according to the Swedish test SP Fire 105 are presented, one series for different shares of untreated wood (partial wood and structural fire protection with a fire shield above the window) and another series for fire retardant treated, FRT, wood. The results are compared with data from the Singl...

The classification system for the reaction to fire performance of building products in Europe has been applied to wood-based panels as being ‘products with known and stable fire performance’. The European classification system includes two sub-systems, one main system for all construction products except floorings and the other for flooring product...

Acoustics is an important performance characteristic for building with wood and a prerequisite for the acceptance of wooden buildings by building industry, building owners and consumers. However, the research in this area has been limited in Sweden during recent years. Therefore, a national consortium was initiated by SP Trätek in 2007 in order to...

The new classification system for the reaction to fire performance of building products in Europe has been applied to five different product families of wood: Wood-based panels, Structural timber, Glued laminated timber, Solid wood panelling and cladding and Wood flooring as being ‘products with known and stable fire performance’. The European clas...

A larger cone heater for the cone calorimeter has been developed in order to measure the rate of heat release from building materials. The aim was to facilitate the testing of inhomogeneous materials and to minimize edge effects. Specimens of two different sizes, 100 × 100mm and 200 × 200mm, were tested in the horizontal orientation. The maximum ra...

Correlations based on linear regressions between data as time to ignition and heat release in the cone calorimeter and time to flashover in the room fire test have been developed. They are a further development of an earlier approach which has been modified and extended to a wider range of surface linings. The correlations apply so far only to surf...

Equipment has been developed for measuring the rate of heat release from building materials in an open test arrangement. The method is based on an oxygen consumption technique. A vertical sample is placed under an open hood in which the combustion gases and a certain amount of air are collected. The decrease in oxygen concentration and the mass flo...

Fire retardants may considerably improve the fire properties of wood products, but the durability, e.g. in exterior applications, has not been addressed fully. This paper reviews the existing knowledge and experience mainly from the USA with the aim of supporting further development in Europe. The review is concentrated on pressure impregnated fire...

Kraft lignin is a by-product of kraft pulping with great potential as an additive for wood composites. Kraft lignin was added to wood chips prior to defibration and alternatively to fibers to improve the properties of fiberboards. Lignin-wood fiberboards were produced on both laboratory and semi-industrial scale using different methods of adding th...

Cone calorimeter tests were performed on specimens made of pieces of wood and pieces of gypsum plasterboards protecting the wood against the heat. The thermal behaviour of the gypsum plasterboards of different origin was studied by determining the time to onset of charring and the charring rate of wood. The specimens were exposed to a constant heat...

The charring of wood studs has been studied in the cone calorimeter at constant heat flux 50 kW/m2 and compared to data from full-scale furnace wall tests. The wood studs were unprotected or protected by gypsum plasterboards on the exposed side. Similar charring depths were found and the data analysed mainly in terms of fire exposure. A simple smal...

The Cone Calorimeter has been used for fire testing of different products on a small scale for almost a decade. However, the number of users has been increasing in the last two to three years. More experimentation with the apparatus has led to practical questions. One of these is about the use of a retainer frame which has been used mainly for buil...

The smoke production rates for 13 different surface lining materials have been determined in the cone calorimeter at three irradiance levels: 25, 50 and 75 kW/m2. Two light systems have been used simultaneously, a helium-neon laser and a white light source, showing equal results. Different smoke parameters obtained in the cone calorimeter have been...

A very simple empirical relationship has been found for predicting the time to flashover in a full-scale room fire test for surface lining materials. It is based on bench-scale measurements of rate of heat release in the cone calorimeter. The relation also includes the time to ignition and the density of the linings. Where T is time to flashover in...

The contribution from different types of building panels to the total fire resistance of a construction has been determined experimentally by testing in furnaces of three different sizes. The agreement between a full size furnace according to IS0 834 and a small size furnace is good, while a medium size furnace gives a somewhat higher fire resistan...

Three test methods for measuring the rate of heat release, RHR, have been compared on the same building materials. The test methods are the OSU-box modified for O2-consumption, the STFI open arrangement and the NBS cone calorimeter. All methods are based on the oxygen-consumption technique. Radiation intensities up to 50 k Wm−2 have been applied. T...

The immediate tensile strength parameters for spruce parallel to the grain and for hardboard have been determined at equilibrium conditions at temperatures up to 250C. Below 100C the moisture content has been varied between 0 and 30%. Above 100C dry samples have been studied. An increase in moisture content up to about 12% leads to a slight increas...

Two types of fire retardant insulating wood-fiber boards have been developed in laboratory and mill scale. Both include treatments which are incorporated in the normal wet process for manufacturing such boards with a concentration of the fire retardant to one side of the board. One type involves addition of a calcium borate mineral, colemanite, to...

The equilibrium tensile properties of urea-formaldehyde (UF)- and phenol-formaldehyde (PF)-bonded particle boards have been studied at moisture contents between 1 and 33% and at temperatures between −15°C and +45°C. These conditions may occur e.g. during exterior use of the boards. The tensile strength and the modulus of elasticity decrease slightl...

Ignitability, one of the new fire test methods for building materials developing within the International Standards Organization is compared with the national fire test methods in Austria, Britain, France, Germany and Scandinavia. Different commercial wood-based panels have been tested, including fire retardant treated panels. The International Sta...

The degree of permanent indentation in wood-frame hardboard doors due to low energy impact, which is not strong enough to break the board, can be evaluated on small hardboard samples (e.g. 100 mm40mm). The core material of such doors is usually a paper-honeycomb. A test method for such small board samples is proposed. Steel spheres or cones can be...

The biochemical and chemical oxygen demands of carbohydrates depend on the degree of polymerization. This is illustrated by a comparison of xylose with a xylan from birch (DP 200) and galacturonic acid with polygalacturonic acid (DP 80). The polymers have a lower and slower biochemical oxygen demand and a lower chemical oxygen demand, especially if...

Fire retarded treated (FRT) wood products resemble a group of building products that during the last decades has become more common in use. The products are however inhomogeneous materials, and small specimens cut from the same batch or plank may show different fire characteristics. The harmonized European classification system requires that most b...

Sweden birgit.ostman@tratek.se Degrees in Natural Sciences from Lund and Stockholm universities. Active in fire research for almost twenty five years. Main interest in reaction to fire, but experience also in areas as fire resistance and active fire protection. Summary Fire regulations form the main obstacle to the use of wood in buildings in many...

I utredningen ”Mer trä i byggandet”, Ds 2004:01, som ledde fram till Nationella träbyggnadsstrategin slogs fast att: för att öka träbyggandet krävs utbildningsinsatser både av studenter och via fortbildning av yrkesverksamma ute i arbetslivet. Denna rapport är en sammanfattning av kunskaperna vunna ur de aktiviteter som genomfördes inom Nationella...

Interflam 2010. Proceedings of the twelfth international conference, 419-428

SP Report 2010 : 19