Re: What are the reducing and oxidizing regions of a flame?

The region of the reaction where all the "stuff" takes place is a small 
area between the actual fuel ( that which is being oxidized ), and the 
flame and smoke (reduction) called the "flame interface. If you were to 
strike a match and observe its burning process closely you will notice 
that the flame does not actually touch the match. The space between the 
flame and the match is the flame interface and this is where all the 
chemical majic, i.e. oxidation-reduction reaction is taking place. It is, 
as you already know, a straightforward chemical chain reaction. This is 
all the result of rethinking the old fire triangle which used to 
illustrate that it took 3 things to make and sustain a fire: 1.) fuel, 2.) 
heat, and 3.) at least 16% oxygen. The fire tetrahedron has since took its 
place in the past forty years or so adding to the above threee criteria 
the fourth element of fire theory which is the chemical chain reaction.

For a simple flame test, the hottest part of the fire is just above the 
flame. A good analogy would be the sun. The sun's corona is much hotter 
than the sun's surface, by a million degrees or more. 

Most of the answer comes from the Internation Fire Service Training 
Association's publication, Essentials of Firefighting, the standard by 
which most fire cadets are introduced to the basics of firefighting.
You can also do a search on most search engines via the internet by using
"fire tetrahedron" or "fire chemistry". 

Thank you for the question,

Donald E Duggan