The definitions you’ve linked above do not contradict what I’ve posted below or how I’ve described the behavior in the article. You’re running a narrow definition, I’m running a broad definition, the distinction is really fine and neither is wrong.

From the linked Wikipedia article I linked above:

Ok so a couple things here. You mention your knowledge is decades old. If you’re talking more than two decades ago there’s a chance your definition was correct a very long time ago. But to be clear, today in the year of our lord 2025, in the United States of America, your definition is not correct. There are no “narrow” and “broad” definitions. There is a single definition for each in the context of firefighting in the U.S.

One of the things you’ll want to get in the habit of doing, is not quoting Wikipedia as your source, but rather the source that Wikipedia refers to when it says something:

there is considerable disagreement about categorizing backdrafts as flashovers

The disagreement mentioned here refers to the long history of loose definitions in the distant past of fire science as these phenomena were being studied and categorized, as well as differences between scientific and firefighting applications, and European/ US entities. If you follow that reference in your quote [5],

You’ll see it goes over the history of the terms and how we’ve ended up with the current definitions. In the U.S. based fire service, the be-all end-all of these terms in NFPA 921-2004 which is as follows:

The newly crafted NFPA 921-2004 definition of flashover is: “A transitional phase in the development of a compartment fire in which surfaces exposed to thermal radiation reach ignition temperature more or less simultaneously and fire spreads rapidly throughout the space resulting in full room involvement or total involvement of the compartment or enclosed area.”

The source goes on to explain:

However, for firefighting purposes, the NFPA have recognized for over twenty years (in their annual reports concerning firefighter life losses) that there are several other forms of related phenomena or terms used, such as smoke explosion; flameover; backdraft; flash fire; etc and that many of these phenomena cannot be explained or directly attributed by on-scene firefighters.

Therefore, the NFPA reporting system has established the term ‘Rapid Fire Progress’ to cover all situations where some form of fire phenomena led to an extreme event of combustion causing sudden transition from a small fire to a large fire, even where flaming is not sustained. They further refer to various sudden or extreme fire phenomena as falling into one of three categories:

• Flashover
• Backdraft (Backdraught)
• Fire Gas Ignitions

The whole “All backdrafts are flashovers but not all flashovers are backdrafts” comes from studies done by the Swedes in the 1980s which, depending on how long ago you spoke with your lieutenant, may have been what he was referring to. The source article touches on these as well, but again, these are not acceptable terms today.

So if in your article you wanted to use the non-specific broad definition of these phenomena, you’d use “Rapid Fire Progress”. But if you wanted to use terms like flashover or backdraft, you’d need to use the correct one for the phenomena you’re trying to describe because they are not interchangeable any longer.

Here is another great article in PDF format about RFP and its categories that really goes into detail on their differences. It also explains the issue I take with your article, which is that these terms are still to this day sometimes casually misused as if they’re unimportant and interchangeable. This is harmful when presented in an educational context (like your article is to some degree), because these terms need to be clear, distinct, and have a universal meaning so that conditions can be accurately communicated when you’re fighting a fire.