Introduction

The physical burning of wood is a chemical process. When wood is exposed to high temperatures, the process of pyrolysis (chemical change due to heat) begins. Certain components of wood are converted into flammable gases or vapors, and when combined with oxygen, the resultant oxidation of these gases produces a visible flame.

• By-products of burning wood:
  • Water (in the form of steam)
  • Char or charcoal (primarily carbon)
• Charcoal combustion:
  • Charcoal burns with greater heat than the basic components of the wood.
• Factors affecting charring:
  • If carbon or charcoal continues to burn for a long period of time, the depth of charring will be more significant.
  • If an accelerant (such as gasoline) is introduced, the charring depth will increase.

The purpose of the Char Depth Gauge is to determine just how deep the charring actually is. This measurement will aid in determining several important factors related to:

• Fire behavior
• Wood combustion efficiency
• Fire safety assessments