Recent firefighter line of duty deaths as a result of rapid fire progression have highlighted that there is a deficiency in firefighters’ understanding of the fire dynamics created by modern, synthetic fuels on the fireground, and how their tactics may influence these conditions. In particular, the rapid growth of these modern fires, their response to ventilation, and their propensity to become underventilated have changed when compared to their legacy counterparts. Among the reasons for this gap in understanding is the way in which firefighters conduct live fire training. Typical fuels used for firefighter training, such as pallets and straw, are more typical of legacy fuels than modern, synthetic fuels, however. Recognizing this, many instructors have begun to introduce synthetic materials into live fire training, in an effort to make the training feel more realistic. While these fuels may exhibit fire behavior more representative of a room and contents fire with modern furnishings, they also create the potential for hazardous conditions for firefighters. A series of eight experiments was conducted in a concrete fire training building. Two training fuel packages were considered. The first consisted of wooden pallets and straw, a common fire training fuel. The second introduced oriented strand board (OSB) to the pallets and straw fuel package. Both of these training fuels were compared to a room with furnishings similar to those that may be found in a residential home. The results indicated that pallets and straw fail to replicate the high radiant heat flux, underventilated conditions, and rapid response to additional ventilation that was noted in the furnished room fire. Further, since the concrete training building had several built-in ventilation points, and additional ventilation resulted in no increase in thermal conditions, the pallets and straw training fires could be considered fuel limited. In the OSB experiments, on the other hand, a limited growth secondary to ventilation was observed. Thus, the OSB fires represent a more realistic simulation of a furnished room fire than the pallets and straw. In addition to increased fidelity, the OSB training fires exhibited more severe thermal conditions, which would pose a greater hazard to students and instructors than in the pallets and straw evolutions. Thus, if fire instructors should elect to include synthetic materials, such as OSB, into live fire training evolutions, additional precautions must be taken to ensure that participants are not exposed to excessive thermal conditions. Likewise, if instructors choose pallets and straw as a training fuel because of the increased margin of safety, special emphasis must be placed on the difference in fire behavior between the training fuel and the modern, synthetic fuels that would be encountered on the fireground.
- Когда мистер Беккер найдет ключ, он будет вознагражден сполна. ГЛАВА 22 Дэвид Беккер быстро подошел к койке и посмотрел на спящего старика. Правое запястье в гипсе. На вид за шестьдесят, может быть, около семидесяти.
Белоснежные волосы аккуратно зачесаны набок, в центре лба темно-красный рубец, тянущийся к правому глазу.