Site Selection of Rural Fire Stations and Safety Services Using Network Analysis and AHP, Case Study: Shirvanchardavol County

Introduction
The fire services play a key role in safety issues for any country. The operations of the services have a high visibility since the public is aware of its own vulnerability and possibly vital reliance on the service. Firemen and women are rightly admired, particularly as their intervention may carry a risk to their own lives. More generally, this service comes at a considerable cost. The fire and as a result natural and man-made disasters are an integral part of the settlements. Safety and fire services in rural areas due to its proximity to rural farm lands, forest and grasslands with high fire potential is very important. Location of fire stations is an important factor in their ability to protect against fire. In the recent years, fire safety and service development is considered by the governor's agenda. For this reason, one of the major concerns is the location of fire stations to provide services in minimum time required. This study aimed to assess the villages covered by fire services and locate new stations for full coverage of the villages of the county of ShirvanChrdavolin.
 
Theories
Time is the critical element when an emergency is reported. Fire combustion can expand very rapidly in short period of time. Time is the critical factor for the rescue of occupants and the application of extinguishing agents to minimize loss. The time segment between fire ignition and the start of fire suppression has a direct relationship to fire loss. The delivery of emergency medical services is also time critical. Survival rates for some types of medical emergencies are dependent upon rapid intervention by trained emergency medical personnel. In most cases, the sooner trained fire or emergency medical rescue personnel arrive, the greater the chance for survival and conservation of property. Regardless of the speed of growth or length of burn time, all fires go through the same stages of growth. One particular stage emerges as very significant because it marks a critical change in conditions. It is called flashover. Measuring the time to flashover is a function of time and temperature. Fire growth occurs exponentially; that is, fire doubles itself every second of free burn that is allowed. This can be plotted on what is known as the time and temperature curve. There are a number of factors that determine when flashover may occur. These include the type of fuel, the arrangement of the fuels in the room, room size, and so on. Because these factors vary, the exact time to flashover cannot be predicted. Flashover can typically occur from less than 4 to beyond 10 minutes after free burning starts.
 
Methodology
The research was action research in that the information gathered was applied in a real-world context. Response times and distance were selected criteria for this study. A computer modeling approach was chosen for statistical accuracy when tabulating travel times and distances within various geographic areas of the zones serviced by Fire Stations. For this purpose, the combination of AHP and network analysis techniques and overlapping layers were used in ArcGIS environment. The architecture of the GIS is developed based on the concept of network. A network is defined as a set of points (known as nodes) and a set of arcs where each branch connects a pair of nodes. The GIS will help determine which is the shortest path from A to F by: (1) locating the nodes in a map, (2) measuring the distance of each arc, (3) measuring the distance of each path by combining the distances of the connected arcs for each path, and (4) comparing the paths to find the shortest path.
Comprehensive GIS-based fire station site selection study can be the central component for a master plan for fire station locations. This plan can show both the efficiencies and deficiencies of current fire station coverage for a specified travel time and provide a model for future fire station coverage using the specified or other travel time standards.  Statistical population of this paper was dehyaries and elites people in rural of ShirvanChrdavol County. Required data and maps were also collected and updated from the relevant executive agencies.
 
Conclusion
Research results show that there are four urban fire stations and one rural fire station in the area under study that with a response time of 6 minutes only 19% of villages are covered by the stations. According to overlapping layers and reassessment of network analysis, 21 new Fire Stations were identified. According to Population and number of villages covered by each station, proposed stations were prioritized. In addition to identifying the location of the building in terms of locating fire stations, it should be considered within the context of rural physical structure.