This work has been made as a thesis for a BSc degree in Fire Protection Engineering at Lund University. The work has been supported and funded by ESS AB, European Spallation Source, in Lund. ESS AB is a publicly held company, owned by Sweden and Denmark as host countries. These host countries, together with at least 17 other European countries, will build and establish a multidisciplinary research center just outside of Lund. The research will be based on the world's most powerful neutron source and be 30 times brighter than the leading active facilities today. The scope and objective of this work was to evaluate and determine fire properties for a material that will be used for radiation shielding at the Research center. Traditionally two materials, borated paraffin and borated polyethylene, are used for radiation shielding at neutron-based research laboratories. Since base paraffin and base polyethylene are known as combustible materials with a high-energy content, it is of great interest to determine the actual fire properties of the borated versions. As the application of the borated paraffin will be in encapsulated blockhouse wax walls of steel, the prioritized objective in this paper was to evaluate the borated polyethylene that was initially considered to be used as unprotected sheets for radiation shielding. The borated polyethylene was bought at a global supplier of plastic products. Some current building regulations together with valuable information concerning the material were also discussed. The results of the work are based on literature research, interviews, discussions and test methods (cone calorimeter tests, parallel panel tests and combustion under an exhaust hood). Limitations of the work are that it does not consider toxicity, smoke production or a measured heat release rate in the full scale tests. The Euroclass classification according to European fire classification of materials, construction products and building elements was only in the application as a construction product or surface lining and not as flooring. The evaluation of borated polyethylene shows that the fire properties vary depending on the orientation of the material. When burning in a horizontal orientation the Boron oxide establish a suffocating residue layer that dampens the release of pyrolysis gases but in vertical orientation the Boron oxide runs off with the melted material and does not form a suffocating residue layer. When burning in vertical orientation the borated polyethylene also has burning droplets. Values obtained in cone calorimeter tests were used in a screening method, Conetools, to determine the borated polyethylene as D-classified material according the Euroclasses by the European fire classification of materials, construction products and building elements. The actual classification and the burning droplets demands fire protection measures in most building classes according a simplified design by the Building Regulations of the Swedish Board of Housing, Building and Planning, BBR. Future work to ensure a safe use of combustible materials for radiation shielding should be to verify the actual applications of fire protections measures. This verification is strengthened in the guideline BFS 2013:11 chapter 3.4 Skyddad brandenergi (Swedish). Further on in the future it would be interesting to develop a new material for radiation shielding that can be used as self-supporting building elements with fire properties that does not demand fire protection measures or extended fire protection systems.
|Titel på värdpublikation||Fire and Materials 2015 - 14th International Conference and Exhibition, Proceedings|
|Förlag||Interscience Communications Ltd|
|Status||Published - 2015|
|Evenemang||14th International Conference and Exhibition on Fire and Materials 2015 - San Francisco, USA|
Varaktighet: 2015 feb. 2 → 2015 feb. 4
|Konferens||14th International Conference and Exhibition on Fire and Materials 2015|
|Period||2015/02/02 → 2015/02/04|