How wide should a firebreak or fireguard be?

There is no set standard, but it should be wide enough for the fuels along the boundary of the burn unit. Typically a bareground line 4 to 10 feet wide is sufficient, but narrow cow trails and even mowed lines can be safely used. The width of the firebreak can be offset by reducing the amount of fuel right next to the edge of the burn unit by mowing or shredding to diminish flame heights and fire intensity.