Just on a related note - it isn't always safe to assume that sprinkler operation follows a sequential concentric pattern. A recent article in the Journal of Fire Protection Engineering describes studies done at Factory Mutual some years ago on the subject. The article can be found at http://jfe.sagepub.com. The title, authors, and edition as well as the abstract are provided below.
An Investigation of the Causative Mechanism of Sprinkler Skipping Paul A. Croce, John P. Hill, and Yibing Xin Journal of Fire Protection Engineering, 5 2005; vol. 15: pp. 107 - 136. ...Investigation of the Causative Mechanism of Sprinkler Skipping Paul A. Croce FM Global Research...of this work is to identify the cause of sprinkler skipping, a phenomenon whereby sprinklers operate out of the expected sequence. Abstract: The purpose of this work is to identify the cause of sprinkler skipping, a phenomenon whereby sprinklers operate out of the expected sequence. From a list of several mechanisms, three feasible ones are selected for investigation i.e., impingement of water droplets from previously activated sprinklers onto fusible elements, condensation of water vapor onto fusible elements, and entrainment of hot gases into the spray of operating sprinklers. New instrumentation is developed in order to make psychrometric and spray cooling measurements in the ceiling flow of a large-scale fire. A series of large-scale fire tests using these instruments and a controlled heptane spray fire source are conducted. The results indicate that droplet impingement is the causative mechanism of sprinkler skipping. _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
