- Author
- Arvidson, M.
- Title
- Sprinklerskydd av sagverk: En forstudie. [Automatic Sprinkler Protection of Saw Mills: A Prestudy.]
- Coporate
- Swedish National Testing and Research Institute, Boras, Sweden
- Report
- SP REPORT 1995:63, 1995, 78 p.
- Keywords
- sprinklers | wood | literature reviews | statistics | sprinkler systems | costs | industries | quick response sprinklers | spray sprinklers | antifreezes
- Abstract
- [ABSTRACT IN ENGLISH] During the period 1985-1995, the property loss related to fires in Swedish sawmills exceeds SEK 1100 Mkr. Fire loss statistics from 374 fires shows that fires are most likely to occur in the sawing shed (37%), planning mill (13%) and the boiler plant (13%). Fires are less probable in lumber sorters, in wood waste and in dry kilns (between 5-8%, respectively). The primary causes of fire are the equipment used. Overheating and spark formation represents more than 25% of all events. In addition, 20% of the fires are initiated by equipment, where the reason is not found. Miscellanous electricity and cutting/welding activities are the cause in 15% of the cases, respectively. Incendiarism is the cause in 6%, and spontaneous ignition in only 2% of the cases. A properly installed sprinkler system could reduce the loss with approximately 80%. Reduction in cost for the installation would most likely increase the number of installations. The second part of this study investigated the possibility to lower the cost, using alternative technologies. Compared to traditional sprinkler technology the ESFR (Early Suppression Fast Response) sprinkler technology offers a higher degree of protection to a lower cost. For saw mills, ESFR sprinklers would have the potential to reduce the cost for the protection of lumber sorters. Unfortunately, with the current design of the sorters, with a high degree of dense packed lumber, the ESFR technique is not useful. In addition, ESFR sprinklers are limited to wet pipe systems. However, other types of sprinklers might be used to decrease the number of sprinklers operating in a fire or to reduce the water pressure needed. By tradition, conventional type (Duropean style or Old-style), intermediate temperature rated sprinkler are the most common used in saw mills. This study shows that high temperature rated U.S. spray sprinkler could be beneficial. It would also be beneficial to use ELO (Extra Large Orifice) sprinklers where high water densities are required. In general, however, quick response sprinklers would not be advantageous. A major part of the cost for a sprinkler installation is associated with the water supply. The cost might be reduced with other types of reservoirs than the most common types which are manufactured from concrete or steel. When smaller water volumes are required pressure tanks could be an economical alternative. The study also identifies areas where more research or testing are needed, such as the potential effect from antifreeze solutions on fires, a change of the design of lumber sorters, the change in reliability with only one pump instead of two, or with a pressure tank and the development of new types of sprinklers.