A Quantitative Approach to Selecting Nozzle Flow Rate and Stream, Part 2

摘要

Even the smallest flow rate nozzle, regard-less of stream type, if operated long enough, can suppress any fire in a confined compartment. However, when the lives of trapped occupants or firefighters are at stake, an aggressive stream that can effect a rapid knockdown is needed to place an effective volume of water between the occupants and the advancing fire without steaming those people within the compartment or areas opposite the applied stream. As discussed above, the modern-day engine company should expect that its arrival time is in line with a flashover event. As provided by the National Institute of Standards and Technology (NIST) in the April 2010 report on Residential Fireground Field Experiments, a timed three-person engine company and a four-person engine company began applying water to the room-and-contents fires with an "early arrival," at 11 minutes and 24 seconds and 11 minutes and 11 seconds, respectively, with the fires producing a high release rate (HRR) of 1-2 megawatt (MW), which is within the HRR ranges necessary to induce a flashover.~1