This report begins with a discussion of the mechanisms of flame spread over combustible materials while describing the NBCC prescriptive solutions that establish the acceptable fire performance of interior finish materials. It is noted that while flame spread ratings do give an indication of the fire performance of products in building fires, the data generated are not useful as input to fire models that predict fire growth in buildings.
The cone calorimeter test is then described in some detail. Basic data generated in the cone calorimeter on the time to ignition and heat release rates are shown to be fundamental properties of wood products which can be useful as input to fire models for predicting fire growth in buildings.
The report concludes with the recommendation that it would be useful to run an extensive set of cone calorimeter tests on SCL, glue-laminated timber and CLT products. The fundamental data could be most useful for validating models for predicting flame spread ratings of massive timber products and useful as input to comprehensive computer fire models that predict the course of fire in buildings. It is also argued that the cone calorimeter would be a useful tool in assessing fire performance during product development and for quality control purposes.
The objective of this project is to establish fundamental fire performance data for the design and specification of NLT assemblies; this project specially addresses determining FSRs for NLT. The goal of this project is to confirm that NLT, when used as a mass timber element, has a lower FSR than standard thickness SPF boards when tested individually and flatwise. The project also considers how the surface profiles, design details, and the direction of an assembly might influence flame spread. This includes the evaluation of typical architectural features, such as a 'fluted' profile.
Fire Resistance Characteristics of Glued Laminated Timber Manufactured from Malaysian Tropical Hardwood Timber (Malagangai): Charring Rate and Fire Classification
This paper reports the investigation on the one-dimensional charring rate of glued laminated timber manufactured from Malaysian Tropical Hardwood namely Malagangai (density, 800 kg/m 3 ). The fire test was conducted at SP Wood Technology in Stockholm in accordance with EN 13381-7:2014 for determination of charring rate. The reaction-to-fire tests for fire classifications in terms of flame spread, smoke production and burning droplets were investigated at University of Stuttgart, Germany in accordance with the procedures given in EN 13 501-1 : 2010. The results show that the charring rate of glulam Malagangai is 0.6 mm/min. The fire behaviour of the glulam is in Class C with medium smoke generation and very little burning droplets.
This paper provides understanding of the fire performance of exposed cross-laminated-timber (CLT) in large enclosures. An office-type configuration has been represented by a 3.75 by 7.6 by 2.4 m high enclosure constructed of non-combustible blockwork walls, with a large opening on one long face. Three experiments are described in which propane-fuelled burners created a line fire that impinged on different ceiling types. The first experiment had a non-combustible ceiling lining in which the burners were set to provide flames that extended approximately halfway along the underside of the ceiling. Two further experiments used exposed 160 mm thick (40-20-40-20-40 mm) loaded CLT panels with a standard polyurethane adhesive between lamella in one experiment and a modified polyurethane adhesive in the other. Measurements included radiative heat flux to the ceiling and the floor, temperatures within the depth of the CLT and the mass loss of the panels. Results show the initial peak rate of heat release with the exposed CLT was up to three times greater when compared with the non-combustible lining. As char formed, this stabilised at approximately one and a half times that of the non-combustible lining. Premature char fall-off (due to bond-line failure) was observed close to the burners in the CLT using standard polyurethane adhesive. However, both exposed CLT ceiling experiments underwent auto-extinction of flaming combustion once the burners were switched off.
Project contact is Christian Dagenais at Université Laval
Summary
The use of materials in a building is traditionally determined from its combustibility (via ULC S114 or ULC S135) and by its flame propagation index (via ULC S102). The ULC S102 Flame Spread Test, developed in 1943, has historically reduced risk through its method of classifying materials. However, this test does not provide quantitative information on the combustion properties of materials, such as heat flow. The latter is one of the most important variables in the development of a fire. Thus, a new approach would be preferable in order to review the classification of materials according to ULC S102 and ULC S135 (cone calorimeter). The objective of this project is to develop a new approach to classifying materials based on cone calorimeter test results. These results can subsequently be used in numerical modeling as part of a fire safety engineering design. A significant amount of cone calorimeter (ULC S135) testing of materials currently evaluated according to ULC S102 will be required.
The key objective of this study was to evaluate the surface burning characteristics (flame spread rating) of glued-laminated timber (glulam) decking in accordance with CAN/ULC S102 test method. This is part of a test series aimed at evaluating the flame spread rating of mass timber components, such as cross-laminated timber (CLT) and structural composite lumber (SCL).
More specifically, this study is solely focused on mass timber assemblies that are thick enough to be treated theoretically as semi-infinite solids (thermally thick solids) as opposed to thermally-thin, which is typical of traditional combustible finish products. The tested specimen in this series meets the provisions related to "heavy timber construction", per paragraph 3.1.4.7 of Division B of the National Building Code of Canada.
In an objective to evaluate the surface burning characteristics of massive timber assemblies such as CLT and SCL, flame spread tests on massive timber assemblies have been conducted in accordance with ULC S102 test method. This study evaluated the flame spread of fully exposed massive timber specimens (i.e. untreated/uncoated) as well as the effect on flame spread by using intumescent coating with CLT. Test results provide low flame spread ratings when compared to those of common combustible interior finish materials provided in Appendix D-3 of NBCC. Specifically, the obtained flame spread ratings of 3-ply CLT assemblies of 105 mm in thickness are 35 and 25 for a fully exposed CLT (untreated) and for a CLT panel protected by intumescent coating respectively. Fully exposed SCL of 89 mm in thickness provided ratings of 35 and 75 for parallel strand lumber (PSL) and laminated strand lumber (LSL) respectively.
Advanced wood building systems form a significant market opportunity for use of wood in taller and larger buildings, which are currently required to be of non-combustible construction in accordance with provisions set forth in Part 3 of Division B of the National Building Code of Canada (NBCC).
In order to evaluate the surface burning characteristics of massive timber assemblies, flame spread tests on CLT assemblies have been conducted in accordance with ULC S102 test method. Three series of 3-ply CLT panels of 99 mm in thickness, V2 stress grade as per ANSI/APA PRG-320 (i.e., manufactured with Spruce-Pine-Fir (SPF) lumber) have been evaluated for flame spread and smoke developed classification. Fully exposed CLT specimens (99 mm) provided much lower flame spread ratings (FSR of 40), when compared to thinner similar products.
The rate at which flame spreads on the exposed interior surfaces or a room or space can have an impact on the rate of fire growth within an area, especially if the materials of the exposed surfaces are highly flammable. Therefore, the National Building Code of Canada (NBC) regulates the surface flammability of any material that forms part of the interior surface of walls, ceilings and, in some cases, floors, in buildings. Based on a standard fire-test method, the NBC uses a rating system to quantify surface flammability that allows comparison of one material to another, and the ratings within that system are called flame-spread ratings (FSR).
%3a+Charring+Rate+and+Fire+Classification){kind=link}
