What is a burn window?

• A. The duration from ignition to containment.
• B. The forecasted weather for the burn day.
• C. The planned ignition rate and spacing during ignition.
• D. The time period when weather and fuel conditions meet the prescription for safe and effective burning.

Answer: (D)

A burn window is the period when weather and fuel conditions align with the prescribed criteria, making a burn safe and effective. This is the timeframe you target for ignition because it matches the safety and performance requirements set during planning. It’s not the total time from ignition to containment, nor the day’s forecast, nor the ignition rate and spacing—that would be planning or operational details outside the window concept. If conditions move outside the prescription (for example, wind shifts, humidity rises or falls beyond limits, or fuels are drier or wetter than allowed), the burn window can close and ignition should be delayed or stopped.