A fuel break is an existing, planned change or discontinuity in fuel that will reduce the likelihood of combustion, fire intensity and/or the rate of firespread.
In preventing firespread, the position of separating walls and other firebreaks that could help with checking the spread of fire should be considered. In modern buildings with fire-resisting floors, horizontal fire travel is more usual, while in older buildings the spread of fire tends to be in a more vertical direction.
Also refer to Wildfires and Environmental protection