Not just what and how, but why!
This is the fourth in a series of posts dealing with flashover, to review prior posts see: Understanding Flashover: Myths and Misconceptions Understanding Flashover: Myths and Misconceptions: Part 2 The Ventilation Paradox As previously discussed flashover requires sufficient heat release rate for the temperature of fuel packages within a compartment to increase sufficiently to ignite … Read more
Reading the Fire Heat Indicators briefly examined energy, temperature, and heat in thermodynamic systems, and introduced the two major categories of heat related fire behavior indicators: those that we can see (visual) and others that can be felt (tactile) as illustrated in Figure 1. Figure 1. Basic Heat Indicator Categories Heat Indicators Part 2 elaborated … Read more
As discussed in prior Reading the Fire posts and the ongoing series examining fire behavior indicators (FBI) using the B-SAHF (Building, Smoke, Air Track, Heat, and Flame) organizing scheme, developing proficiency requires practice. This post provides an opportunity to exercise your skills using three video segments shot during a commercial fire. In addition to practicing … Read more
Reading the Fire Heat Indicators briefly examined energy, temperature, and heat in thermodynamic systems, and introduced the two major categories of heat related fire behavior indicators: those that we can see (visual) and others that can be felt (tactile) as illustrated in Figure 1. Figure 1. Basic Heat Indicator Categories As with each of the … Read more
I originally intended to write this post about the influence of air track on flashover in multiple compartments. However, after several conversations in the last week about the bathtub analogy and ventilation induced flashover, I had a change in plans. The Bathtub Analogy In Understanding Flashover: Myths and Misconceptions, I presented the bathtub analogy (Kennedy … Read more
In Reading the Fire: How to Improve Your Skills, I discussed building a concept map of fire behavior indicators as a method to increase competence in reading the fire. Construction of a concept map increases awareness of key indicators and understanding their interrelationships. I am working through this process along with you, with the latest … Read more
Just over a year ago I had the idea to develop a blog focused on compartment fire behavior and firefighting. A bit of work on the technology side and I made my introductory post on 8 August 2008. That month the CFBT-US web site had 2900 page views, this past July the page view count … Read more
A Quick Review The first post in this series, Understanding Flashover: Myths & Misconceptions provided a definition of flashover and examined this extreme fire behavior phenomenon in the context of fire development in a compartment. Flashover is the sudden transition to fully developed fire. This phenomenon involves a rapid transition to a state of total … Read more
Air track includes factors related to the movement of smoke out of the compartment or building and the movement of air into the fire. Air track is caused by pressure differentials inside and outside the compartment and by gravity current (differences in density between the hot smoke and cooler air). Air track indicators include velocity, … Read more
Flashover is likely the most common type of extreme fire behavior encountered in structural firefighting. As my friends and colleagues from Sweden frequently observe, this is not really extreme fire behavior, its normal fire behavior. I think it is both. The term extreme “is framed within the context of our perception with ‘extreme’ defining our … Read more