Fire performance characteristics of acetylated ash (Fraxinus excelsior L.) wood

Abstract

Wood acetylation with acetic anhydride is used to reduce swelling and shrinkage in changing humidity as well as to protect against biological deterioration in an environmentally acceptable manner. Changes in the chemical composition of wood will influence its fire performance. The objective of this investigation was to estimate the influence of wood acetylation on the reaction of wood to fire. Acetylated and untreated ash wood parquet boards conditioned according to EN 13238:2002 were tested for their reaction to fire on flooring radiant panel equipment and on a cone calorimeter according to EN ISO 9239-1:2002 and ISO 5660-1:2002. Acetylation diminished the performance of the wood on reaction to fire compared with untreated wood. It was supposed that acetylation decreased critical heat flux at extinguishment by acetic acid split off in pyrolysis conditions. Burning of acetylated wood produced less smoke than natural wood. In conditions of more intense radiant heat flux the difference in smoke production between acetylated and unmodified wood was less pronounced.

Keywords:

• Acetylation
• cone calorimeter
• flooring radiant panel
• reaction to fire
• wood

Acknowledgements

The authors greatly acknowledge financial support from the European Regional Development Fund and from the Latvian Council of Science Fund, as well as technical support from the Forest and Wood Products and Development Institute.