دانلود رایگان مقاله تشخیص آتش سوزی در محفظه ضروری و خواب راننده اتوبوس

ABSTRACT

Effective fire detection systems properly installed in bus and coach toilet compartments and driver sleeping compartments may save human lives and property loss. Rapid detection allows for early evacuation and extinguishment of a small fire, while late or no detection may allow the fire to spread. The purpose of the work presented in this paper is to provide recommendations on how to install fire detection systems in toilet compartments and driver sleeping compartments. The recommendations also cover what type of detection system is most suited. As a basis for the recommendations, full scale fire tests were performed with different detection systems. The fire tests were conducted in realistic mockups of a toilet compartment and a sleeping compartment. Different heat and smoke detection systems were analyzed at different positions for different fire scenarios to provide information on how to best install detection systems in these compartments. Five different scenarios were run and the most interesting finding was that two realistic fire scenarios in the toilet compartment did not activate fire detectors in the ceiling at realistic air flow rates. It is very rare that fire detectors are placed anywhere else than on the ceiling in toilet compartments on buses and the fire would then be very large upon detection.

4. Discussion and conclusions

According to the new UNECE Reg. no. 107 requirement smoke or heat detectors shall be installed in toilet compartments and driver sleeping compartments of buses. The performed tests have resulted in valuable information of what to consider when installing these detectors. Smoke detectors are generally much faster than heat detectors, which is also confirmed in all tests performed in this study. In the tests the fires have developed quite rapidly, but for slow growing fires the benefit of smoke detectors compared to heat detectors will be even greater. There are locations where heat detection may be considered, e.g., in the concealed space under the sink in toilet compartments or close to the trash can where the detector is expected to be in the immediate vicinity of the fire. In both the paper test and the plastic/rubber test the temperature in the concealed space under the sink was over 100 C after one minute. In very narrow spaces and in other circumstances when the detector is close to the potential fire source heat detectors will also react relatively quickly, although smoke detectors will most often still be faster. The benefits of using heat detectors in these spaces are that they are usually cheaper and more robust. They may also require less maintenance and inspections than smoke detectors that must be inspected regularly to ensure proper functioning. However, heat detectors should only be used as a complement to smoke detectors.