PROTECTION OF SETTLEMENTS AGAINST WILDFIRES

Transcription

1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 9, September 2018, pp , Article ID: IJCIET_09_09_197 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed PROTECTION OF SETTLEMENTS AGAINST WILDFIRES Quang Bon Le, Thanh Hai Nguyen, Khac Lich Pham, Tuan Anh Nguyen University of firefighting and prevention Thanh Xuan, Hanoi, Vietnam ABSTRACT This article discusses the issue of protection of settlements against wildfires. Importance and targets of protection of settlements against wildfires are highlighted. Fire protection tools and equipment applied in various countries are analyzed, such as unmanned aerial vehicles (UAV) for wildfire monitoring, fire lines for localization of wildfires, portable firefighting appliances aimed at improved efficiency of wildfire extinguishing, automatic fire extinguisher robots. Key words: wildfires, rescue fire squads, UAV, portable fire extinguishing appliances, automatic fire extinguisher robots Cite this Article: Quang Bon Le, Thanh Hai Nguyen, Khac Lich Pham, Tuan Anh Nguyen, Protection of Settlements Against Wildfires. International Journal of Civil Engineering and Technology, 9(9), 2018, pp INTRODUCTION Wildfires and their consequences require for necessity to provide protection of human lives and national wealth on the basis of improved fire protection of settlements. Such wildfires destroy not only unique flora and fauna but numerous facilities and buildings in settlements, which results in significant damage to population and overall country. Importance of protection of settlements against wildfires evidences necessity of implementation of state policy in the field of fire safety which is an inherent portion of governmental protection of human life and health, national wealth and environment. Protection of settlements against wildfires is aimed at: protection of life and health of population, environment and facilities against dangerous factors of wildfires; improvement of fire safety in settlements accompanied by material and technical resources of rescue fire squads required for fulfillment of assigned duties; establishment, equipment and optimum dislocation of local rescue fire squads, their provision with regard to issue of prevention and management of consequences of wildfires; compliance of firefighting water supply with requirements of regulations and standards

2 Protection of Settlements Against Wildfires 2. APPLICATION OF UAV FOR WILDFIRE MONITORING Wildfire aerial reconnaissance is an important type of support of rescue fire squads during protection of settlements. Aerial reconnaissance is aimed at data acquisition for determination of degree and hazard to settlements, correct estimation of fire situation and adoption of solution on wildfire suppression. A promising approach to solution of this problem is monitoring of hazardous state during occurrence of wildfires using UAV and on-land appliances of continuous data acquisition in real time concerning impacts of wildfire hazardous factors in combination with on-line forecasting of sizes of hazardous area and respective situation. It would reasonable to apply the aforementioned appliances in order to solve the following targets of aerial reconnaissance: detection of locations of possible wildfires; detection of local fire sources and smoke generation; determination of location of people and animals, determination of existing hazard by wildfire, as well as evacuation routes and methods; determination of location and sizes of wildfire, burning objects, as well as directions and dynamics of fire propagation; monitoring of wildfire suppression; determination of possible ways and directions of introduction and transfer of human staff and fire suppression means; determination of necessity to evacuate material valuables, livestock; routes and methods of their evacuation; evaluation of results of wildfire suppression; evaluation of fire damages and etc. [1]. While performing aerial reconnaissance, it is required to account for time of day and season, as well as atmosphere turbulence in the space where UAV should be used for aerial reconnaissance. Schematic flowchart of on-line monitoring of wildfire boundaries, hazard level and forecasting of new risks is illustrated in Fig. 1. Monitoring of wildfire boundaries, hazard level and possibilities of new wildfires according to opinion of Chinese experts is comprised of the following stages: UAV start (UAV flow is controlled by monitoring center via UAV control unit); continuous monitoring via satellite system (GPS) of UAV location and hazard level near UAV by on-board instruments, inspection by on-board camera and data transfer to ground mobile monitoring center; distribution of monitoring appliances from UAV over wildfire area using parachutes; activation of monitoring center into operation control of appliances; detection of location of monitoring appliances via GPS and adjustment of their locations, if required; installation and activation of sensor of inspecting cameras in wildfire area [2] editor@iaeme.com

3 Quang Bon Le, Thanh Hai Nguyen, Khac Lich Pham, Tuan Anh Nguyen Figure 1. Schematic flowchart of on-line monitoring: a 1 ground mobile monitoring center; b 2 territory of wildfire occurrence; c 3 UAV; d 4 ground automated monitoring appliance of wildfire hazardous factors; e 5 GPS; f 6 damage area; g 7 parachutes for monitoring appliances. When necessary (in order to increase forecasting accuracy; upon expansion of wildfire area, and etc.) additional set of monitoring appliances is delivered to wildfire area. After wildfire suppression all used monitoring appliances are collected by ground mobile monitoring center. Then their operability is checked, batteries are recharged, they are prepared for next operations. This monitoring system enables delivery of ground automated appliances to wildfire area by UAV, it includes location of dispatch station for data acquisition and processing for UAV start on ground mobile platform (command vehicle; rescue fire vehicle; armored fighting vehicle; reconnaissance vehicle, hauler, and etc.). 3. FIRE LINES FOR WILDFIRE LOCALIZATION In order to prevent fire propagation in wild ecosystems and their prevention in settlements, many countries of the world use fire lines comprised of aqueous solutions of chemicals with fire protection properties. The aqueous solutions are applied in required amounts onto forest cover, thus creating fire resistant protecting line which prevents fire propagation. Prior to application, the chemical compositions are dissolved in the required concentration in any tank or reservoir, then they are applied using hoses or drip torches. Firefighting aircrafts are used for installation of fire lines in inaccessible locations. Width of the basic fire lines upon ground wildfires depends on fire intensity. The ends of fire lines should be supported by natural or artificial fire barriers. Modern substances with fire protection properties include, among others, fire retardant FR CROS 134T (Budenheim, Germany) which is intended for laying of long-term fire lines and suppression of wildfires. Field tests demonstrated that fire lines based on 10% aqueous editor@iaeme.com

4 Protection of Settlements Against Wildfires solution upon its application on combustible matter at the rate of kg/m 2, were capable to maintain fire protection properties up to 45 days. The fire retardant is noncorrosive, nontoxic, environmentally safe, fire and explosion proof. The FR CROS 134T fire retardant was successfully tested in Quảng Nam Province (Vietnam). On the basis of experimental results, the retardant was recommended for fire protection in natural ecosystems. Budenheim company informs that in order to treat the wild surface area of 3000 m 2, it is required to prepare solution of 600 l of retardant and 2,400 l of water [3]. 4. PORTABLE FIREFIGHTING APPLIANCES AIMED AT IMPROVED EFFICIENCY OF WILDFIRE EXTINGUISHING According to statistics, about 95% of fires in the world are suppressed by water. Taking into account wide popularity of this fire suppressing substance, it should be mentioned that in practice there are some issues concerning its application, namely: necessity of huge amounts of water, provision of permitted flow rates and pressure, which is important in areas with water deficiency peculiar for rural localities and forests. Nowadays rescue fire squads in the world are equipped with various firefighting tools. Conventionally they can be subdivided into three types: portable, mobile, and stationary. The mentioned tools are characterized by different weights and dimensions (from 50 to 300 kg) and methods of delivery to required place (trailer or rescue vehicle), generally they are comprised of the following components: high pressure pump, fuel tank, high pressure hose, special water monitor, and they can be additionally equipped with tank for fire suppressing substance. Advantages of portable fire protection tools are as follows: quick delivery to fire location and deployment, fire suppression in unapproachable places as well as their high capacity and efficiency. In addition, advanced technologies are constantly developed, including fire suppression using compressed air foam: ONE SEVEN [4], improved by GIMAEX Group S.A.S.Y. (France). ONE SEVEN is a highly efficient extinguishing medium which requires for minor amount of water. This system can be applied for fire suppression under complicated conditions. ONE SEVEN is widely used in many countries of the world, in particular in Germany, France, the USA, Great Britain, and Russia. In addition to ONE SEVEN system, there are other efficient portable tools of fire suppression available for rescue fire squads in many countries of the world such as HDL 70 (Germany), high pressure extinguishing systems REIN and HIPRESS MSA AUER (Germany), HLG HYDROJET and HLG POWERJET (France), high pressure extinguishing system ERMAK (Russia), mobile system CAFS Mobile (Russia) and portable system CAFS 60-P (USA) [3] (Fig. 2). Figure 2. Mobile system (CAFS Mobile, Russia) and portable system (CAFS 60-P, USA) editor@iaeme.com

5 Quang Bon Le, Thanh Hai Nguyen, Khac Lich Pham, Tuan Anh Nguyen Thus, nowadays a promising trend of wildfire suppression is application of portable fire extinguishers equipped with high pressure pumps. The main advantages of such tools are rapid decrease in heat intensity during fire suppression by means of sprayed water jets, moderate consumption of fire suppression substances. 5. AUTOMATIC FIRE EXTINGUISHER ROBOTS Application of automatic fire extinguisher robots (AFER) becomes more and more popular due to impact of hazardous factors on firefighters. AFER is a mechanical appliance based on operation of specialized sensors of environmental perception, software for robot control in this environment, and human operator to control robot functions. Numerous automatic systems are available to support firefighters upon performance of wide scale range of rescue operations, including wildfires. In addition to large amount of fire scenarios, the functional capabilities of the robots can be required to fulfill such firefighter tasks as approaching fire, identification of humans in traps, fire detection, monitoring of fire propagation and fire suppression. There are two types of AFER developed for fire extinguishing: fixed and mobile systems. Fixed systems, such as automatic water monitors, are used in the cases of significant danger of combustion and when the fire should be suppressed as fast as possible. These systems are equipped with UV or IR sensors for targeted directing of fire extinguishing systems to fire center and subsequent localization. Mobile systems are characterized by expanded capabilities to assist operator in navigation, they perform wider range of tasks. Ground mobile AFER for outdoor operation are mainly vehicles with onboard fire extinguishing systems which are remotely controlled by operator. Such AFER move at the speed of km/h on wheels or tracks, their weight is 450-9,300 kg and they are equipped with fire extinguishing systems. These robots are supplied by batteries or equipped with diesel engine. The fire extinguishing systems installed on robots are equipped with water and foam monitors capable to produce compact or sprayed jets. Generally such robots operate with Wi- Fi connection for remote control, data transfer from onboard sensors to operator of navigation and fire extinguishing. The sensors on the robots include IR cameras, gas content sensors, as well as distance meters in order to pass obstacles [5]. Aerial vehicles are also used in many outdoor rescue operations for fire extinguishing. At present military unmanned aircrafts and helicopters are modified for supporting wildfire extinguishing operations. These UAV have larger dimensions (wing length/span), they can transport higher quantities of fire extinguishing substances (up to 3 t), they are equipped with numerous sensors for monitoring and assessment of fire situation. Future application of automatic robots for wildfire extinguishing will depend on their strength, sufficient number of sensors for monitoring and environmental perception, possible tasks, cost, level of independence and travelling speed. Cost is an important factor for fire rescue operations, at present it restricts wider application of robots for fire extinguishing. However, when robots are more efficient for wildfire suppression and firefighters are able to control them in safe shelters, the robots will be applied more intensively for protection of settlements against wildfires. 6. CONCLUSIONS Finally, it should be mentioned that prevention of wildfires is an urgent and important measure; and when wildfire nevertheless occurs, timely response and required personnel with appropriate equipment would efficiently protect settlements against such emergencies. Taking into account global experience as well as possible extensive ranges of the mentioned issue editor@iaeme.com

6 Protection of Settlements Against Wildfires which effects on human life and health, it should be concluded that protection of settlements against wildfires requires for comprehensive approach. REFERENCES [1] Yannikov, I. M., Fomin, P. M., Gabrichidze, T. G. and Zakharov, A. V. Primenenie bespilotnykh letatel'nykh apparatov pri razvedke trudnodostupnykh i masshtabnykh zon chrezvychainykh situatsii [Unmanned aerial vehicles for monitoring of inaccessible and extensive emergency zones]. Vektor nauki TGU, 3(21), 2012, pp [2] Yuan, C., Ghamry, K. A., Liu, Z. and Zhang, Y. Unmanned Aerial Vehicle Based Forest Fire Monitoring and Detection Using Image Processing Technique. Proceedings of 2016 IEEE Chinese Guidance, Navigation and Control Conference, Nanjing, China, August 12-14, [3] Gao, L. P., Wang, D. Y., Wang, Y. Z., WANG Jun-Sheng, YANG Bing. A flameretardant based on a reactive monomer of DODPP and its thermal and flame-retardant properties. Polymer Degradation and Stability, 93, 2008, pp [4] State-Of-The-Art Mobile Fire Fighting Technology for the 21st Century. One Seven Mobile Systems: Fast. Efficient. Safe. content/uploads/2018/05/os_image- Broschuere_Mobile_Loeschtechnik_21_Jahrhundert_ENG_L06_.pdf [5] Chen, T. An automatic fire searching and suppression system for large spaces. Fire safety journal, 39, 2004, pp editor@iaeme.com