Smoke exposure levels prediction following laboratory combustion of Pinus koraiensis plantation surface fuel

Abstract

High concentrations of harmful gases released from forest fire will pose a short-term hazard to fire-fighters' cardiopulmonary function, even threaten their lives. In this study, laboratory experiments were conducted to examine the relationship between harmful gases concentrations and burning environment and fuel characteristics. In the experiments, fuel beds were created with controlled moisture contents and fuel loads; a wind tunnel device was used to conduct 144 trials, each with a specific wind speed. The easily predicted fire behavioral characteristics and the harmful gases concentrations such as CO, CO₂, NOx, SO₂ which were released during fuel combustion were measured and analyzed. The results showed that the influences of wind speed, fuel moisture content, and fuel load on the flame length are in accordance with the fundamental theory of forest combustion. The contributions by controled variables to the influence on the short-term exposure concentration of CO and CO₂ can be ranked as fuel load > wind speed > fuel moisture. The R² of the established linear model that was used to predict Mixed Exposure Ratio was 0.98. Our results can help protect the health and lives of forest fire-fighters and can be used by forest fire smoke management to guide fire suppression.

Keywords: Fire behavior; Mixed exposure ratio; Pinus koraiensis; Random Forest; short-term exposure concentration.