A case study of a real forest fire incident is presented, where field measurements held out near the flame-front in smoky, hostile conditions. Permanent gases, such as CO, CO2, NH3, volatile organic compounds (VOCs) and particulate matter (PM2.5, PM10) were monitored. Complexity and possible origin of some of the forest fire smoke components are examined and discussed; styrene identified seems that was originated mostly from the combustion of plastics, due to the forest fire expansion to a plastics storehouse. A new approach, regarding the chemical composition of forest fire smoke and possible origin of smoke components depending on the flame-front expansion (e.g. to rural fields, rural and urban constructions or landfills), is presented in the format of a road-map. The case study tests part of the validity of the road-map, which could be used for air-quality indications and risk assessment in a forest fire. Criteria for monitoring air-quality in a forest fire, for health and safety issues, are also discussed. © 2006 Elsevier B.V. All rights reserved.