Title: Fire safety studies: Part 1 - Fire safe building with wood；

　　　　　　　　　　　　　  　　  Part 2 - Forest fires and hazards for buildings

Speaker: Dr. Esko Mikkola
From: VTT Technical Research Centre of Finland
Date: Nov. 26, 2012
Abstract:

Fire safety studies: Part 1 - Fire safe building with wood, Part 2 - Forest fires and hazards for buildings
Part 1
Fire safety engineering has been used to produce justification for protection methods of timber structures under room fire conditions in residential and office buildings. The study included use of measured fire load density and opening factor distributions, use of parametric fire curves and event tree analysis, as well as comparisons with statistical data of real fires.
The requirements for maximum 8 floor building with non-combustible load bearing structures was used as the reference level. Additionally, no sprinklers and no fire brigade intervention were assumed. Fire load density was taken the same as assumed to be in the reference case, 600 MJ/m2 (for floor area).　
In the analysis probabilities for local collapse per ignition in a compartment fire were calculated for protected timber structures and the reference structures. The protection alternatives included different coverings (fire protection ability, EN 14135) with and without sprinklers. As a result both passive and active methods together with performance levels were proposed.
Part 2
Forest and wild land fires do not only burn down forests but do have serious impacts on buildings and infrastructures as well as endanger safety of people. Many fires also occur in the wild land urban interfaces because human activities are most common causes of forest fires.
In principle, there are three heat transfer mechanisms than can cause the ignition of buildings: Radiation from the flames, convection of hot gases and spotting, i.e. transport of hot particles and firebrands. Studies in FIRE PARADOX project have included e.g. prediction of fire conditions at targets and modelling of ignition or damage of building materials. Predictions of radiative heat fluxes and temperatures at target have being analysed as well as transportation of firebrands. Key parameters are the fire front parameters (such as fire front height, depth and width, fire front intensity (MW/unit area)), distance to target, wind speed and target properties (such as materials exposed, openings/ventilation, etc.).