The Importance of Crowd Control in Evacuation - Essay Example

NAME : XXXXXXXXXX TUTOR : XXXXXXXXXX TITLE : XXXXXXXXXXX COURSE : XXXXXXXXXX INSTITUTION : XXXXXXXXXX @2009 The importance of crowd control in evacuation Introduction The movement of large number of people is critical when evacuating individuals from a building in an emergency. In a large crowd, there is a high risk of injury and even death due to the massive forces that are exerted on a single person by the surrounding crowd. Many cases of overcrowding and crushing during emergency situations have been reported. In crowded environment, most individuals are injured or killed by the non-adaptive crowd behaviors of the crowd rather than the actual cause of the catastrophe. Non-adaptive crowd behavior refers to the destructive actions that a crowd may experience in the event of a disaster, for example pushing others out of the way, stampede, knocking others down and stepping on others (Da Silva et al. 2003). Therefore, crowd control is increasingly becoming important in simulating the evacuation of a crowd in emergency situations. This paper will describe the best model in controlling crowds in emergency situations. Understanding the non-adaptive crowd behaviors is critical in development of appropriate crowd control methods to ensure proper evacuation of people from the building in the event of an emergency (Musse 2000). Depending on the complexity of the emergency, simple or complicated behaviors rules can be used to control the crowd. This paper will develop a ViCrowd model to control the crowd using different types of crowd control methods. This will involve creating programmed, autonomous and guided control crowd (Garat et al. 1999). Developing a programmed crowd involves establishing pre-defined behaviors which individuals are supposed to exhibit in case of an emergency. Creating an autonomous crowd involves defining behavior rules that is coming up with rule-based behaviors. Developing a guided crowd involve providing an external control to guide crowd behaviors. These three ways of behavior control in crowd must be used in combination for effective evacuation of the crowd during emergency situations. The guided method of crowd control reduces the average escape time and increases the chances of survival of individuals during emergency situation. Although this paper discusses these three types of crowd control, it focuses more on the different aspects of interaction with the guided crowd. It discusses different interaction paradigms that can be used to interact with the guided crowd (Thalmann and Musse 2001). To create an autonomous crowd, various approaches can be used such as particle, flocking and behavioral systems. The particle systems have been used by many authors to create autonomous crowd by use of physical rules. There is a similarity between fluid and particle motions and crowd movement during an emergency (City of Cincinnati 1980). There are two methods under this system which can be used to evacuate individuals from a building in case of a disaster; the exodus system and the panic simulation system. The exodus system can be useful in simulating the evacuation of large numbers of people from a large storey building. It involve adopting a fluid dynamic models accompanied by distinct practical simulation techniques to track the routes of individuals as they try to move out of the building (Fire Safety Engineering Group 2003). The behavioral systems assume that the autonomous crowd as intelligent enough to make decisions using specific rules. A scripted interface is used to define the action, motion and behavioral rules of the crowd behaviors. The action and motion describe the explicit behaviors of the programmed crowd while the behavior rules define the autonomous crowd. The guided crowd is controlled by an external agent who uses the action, motion and behavioral rules. During emergency, the autonomous crowd is able to act according to the inherent behavior. The simple behavior rules which can be applied by individuals in the event of an emergency include fleeing, obstacle avoidance, wall, path and flow field following, crowd path following, leader following, collision avoidance, queuing at the exit and flocking (Borgan et al. 1998). It is critical to create virtual crowds which have knowledge of the environment in which they are to enable them who are able to interact and move within their environment. Such autonomous crowd is able to obey the organization rules and regulations in the event of an emergency (Helbing et al. 2000). On the other hand, a guided crowd must always be guided by a leader. The leader in this case can be the crowd controller or the evacuation team. When people are in a crowd, they display specific similar characteristics. For example, they all seek a goal, which in this case is to get out of the emergency site as fast as possible. When people are in a crowd they seem to walk together, what we call flocking motion. The rule-based behavior crowd control can therefore be effective in guiding the crowd in the event of an emergency. Social simulation is an excellent example for crowd control during emergency situations (Murakami 2003). Most evacuees choose the exit route that is visible and less overcrowded at that particular moment. The main goal of all evacuees is to find the nearest exit. The evacuees may have no idea of the status of the exit as to whether it is blocked or not. It is therefore more probable that he/she may choose the wrong exit, which may lead to time wastage. It is therefore important for the first evacuee who finds the wrong exit to immediately inform the others who may be following him/her for them to choose another exit. A guide that has a global view of the environment may be used to direct the crowd towards the right exit. The occupant of the building should have information as regard the obstacles that they should avoid as they try to get out of the building in the event of an emergency, such as gas cylinders. The crowd controller can also choose the number and position of obstacles that can be used to prevent overcrowding at the exit locations, such as walls. This allows the evacuees to get out of the exit without pushing each other which can be harmful. The crowd should be aware of the number, the size and position of the exits in the building. When the crowd has formed a queue at the exit of the building, those who are nearest to the exit should be given first priority to avoid overcrowding (Wooldridge and Jennings 1995). It is extremely important to control the crowd during emergency in order to improve their ability to survive in an autonomous way. Many researchers have agreed with the model of intelligent or autonomous agent requirements which include self-directed behavior, action, awareness, memory, reasoning, knowledge and self-control (Still 2000). However, the use of a guide may be preferred as during emergencies, people start moving faster than normal, interaction among people become physical as they constantly push each other, movements becomes uncoordinated, exits becomes overcrowded, where as injured or fallen people become obstacles to the evacuation process. To avoid such confusion, the leader or the guide may decide to use the follow-direction method or the follow-me method to guide the evacuees to the correct path, walls, corridors or exits. In the follow-direction method, the leader should shout out the evacuation instructions to the evacuees, where as, in the follow-me method, the leader should tell the evacuees who are near to him to follow him (Reynolds 1999). Employers should adapt the best and practical guidelines as regards emergency and crowd management practices. It is imperative for employers and agencies to have a thorough knowledge of the current Occupational Health Safety (OHS) laws that are relevant to them. In addition, they should understand the principles and good practices in the workplace that strengthen OHS laws. The five major principles that should be applied to ensure health and safety of the employees include 1) making sure that all the employees have the highest level of protection, 2) those yin position should be responsible for eliminating risks, 3) employers should be proactive in managing risks, 4) information about risks and control should be distributed to all the employees and 5) employees should be entitled to representation (William and Jamie 2003). To effectively control the crowd during an emergency, the crowd controllers should be involved in the decision-making processes as regards issues that will affect their health and safety. It is important to discuss issues regarding the venue’s or event security with those that arte employed to administer such duties. This will provide an opportunity for the identification of gaps that exist in the management of crowd activities and allow for necessary changes to be implemented. The employers should consult the employees and crowd controllers as often as possible on issues that directly affect their health and safety. This should involve identifying risks that may arise from the carrying out some of the business activities, deciding on procedures to control such risks, deciding on the sufficiency of the business emergency facilities, confirming measures for resolving health and safety matters arising from carrying out the business activities, consultation, monitoring employee’s health and workplace conditions and provision of information and training. The employees must share information as regard OHS matters with the employees, give then an opportunity to articulate their opinions on those matters and take their opinions into consideration (Jeffrey et al. 2007). It is important to control the entry and exit locations of the business. Crowd controllers should be employed at the entry of the business to make sure that the smooth flow of the people. Emergency signaling equipment in the event of an emergency should be available at the entry point of the business. The crowd controller should be trained to deal with abusive and aggressive behaviors of the people. The main aim of the crowd controller is to maintain a calm situation. Crowd controllers should therefore be trained on defusing potentially aggressive situations and dealing with abusive individuals, on communication skills to effectively deal with individuals who might be aggressive and on first aid. The crowd controllers should not let any evacuee to get back to the building until the building is declared safe (Schweiss et al 1999). The employer should consult with the crowd controllers as regards crowd control activities which involve safety and security risk evaluations, crowd control safe systems of work, workplace policy, implementation of risk control interventions and changes or addition of emergency facilities, uniform or protective equipment. The emergency evacuation team should look for trapped and disabled persons inside the building. Special arrangement should be put in place to evacuate people on wheal chairs, crutches, frail or elderly and pregnant women. The employer should ensure that first aids facilities are available within the business environment. The crowd controllers should have access to first aid personal protective devices such as gloves, eye protection and resuscitation masks. In addition, they should have a portable first resource kit. Professional counseling should be provided to crowd controllers who experiences trauma when administering first aid (Lystad 1988). A successful and effective evacuation process depends on proper crowd control which can be achieved through complete preplanning, organization and supervision (Hans et al 1998). Planning involve building evacuation organization, coming up with evacuation policy and plans, mechanism for detection and reporting of hazards, evacuation program coordination, communication to direct movement and evacuation and inspection and evaluation. Building evacuation organization involves coming up with a written plan for handling emergencies. Such a plan should include an outline of the emergency evacuation organization plan and priorities which have been agreed upon, including responsibilities and authorities. Detection, emergency warning systems and reporting procedures for hazards should also be provided. There should also be an adequate and effective two-way communication system and establishment of emergency evacuation teams to ensure orderly movement of people. The business management team should come up with an education and training program for all the employees, crowd controllers, evacuation teams and building visitors. This should include a system of personal instruction to each and everyone in the building, appropriate distribution of instructions, posters and evacuation illustrations at strategic locations. Emergency fire procedures details should notably posted in corridors. An evacuation drill program should be established to ensure quick transfer of occupants to safe area (Musse et al. 1998). All the occupants of the building should be provided with an evacuation policy and plan of the organization. Such a policy and plan should include fire diction and fire reporting systems and emergency evacuation and communication system provided by the building, evacuation routes, imminent dangers, central control, evacuation teams and evacuation drills. Detection, automatic alarm systems and automatic sprinklers systems is essential in controlling the crowd for proper evacuation. There should also be a proper method for notifying the occupants to evacuate the building. Priorities should be given to those floors that are directly involved and those that are adjacent to the emergency. Alternate routes of escape should be planed in advance incase the evacuation route become dangerous due to smoke, heat or gasses (Greenwood 1998). Education and training of all the occupant of the building, crowd controllers and evacuation team should be initiated. Newly hired employees should also be included in this program. Inducting a new employee into the workplace is a critical step in ensuring their health and safety. An employee should have a thorough knowledge of the risks involved in carrying out the business activities, the facilities in place to control risk in the workplace, the risk reporting mechanisms systems used in the workplace as well as to know who is in control of emergency events. Refresher courses should also be scheduled on a semi-annual basis for all the evacuation teams, crowd controllers and employees. Pocket-size instructions booklets should be prepared and distributed to every person in the building. The information in these cards should include emergency evacuation procedures, available evacuation routes and proper methods for reporting a threat. Crowd controllers should be trained on the proper use of the available communication systems, basic methods of crowd control, evacuation procedures, basic knowledge of first aid and firefighting techniques (Musse et al. 1997). Conclusion Effective control of the crowd during emergency situations is critical in ensuring an orderly and safe evacuation process. Effective control of the crowd help prevent overcrowding at the exit points which may result to injury or even death of individuals as people push each other in an attempt to flee from the emergency site. There are three basic methods for crowd control, autonomous crowd control, programmed crowd control and the guided crowd control methods. All these methods should be used in combination for effective crowd control in the event of an emergency. In addition, the employers or building owners should adopt good practices for handling emergency situations, which involve creating emergency and evacuation plans in advance, involving the employees or building occupants, crowd controllers and evacuation teams in decision-makings in issues that affect their safety and health and developing adequate and appropriated methods of communication. References Borgan DC. Et al. 1998 Dynamically simulating characters in virtual environments. In IEEE C.G.A., 18(5):58-69. City of Cincinnati 1980 Crowd Management: Report of the Task Force on Crowd Control and Safety, Technical Report. Da Silva A. et al. 2003. PetroSim-A framework to simulate crowds’ behavior in panic situations. International workshop on modeling and applied simulation, Bereggi, Italy. Fire Safety Engineering Group 2003. Building Exodus: the evacuation Model for the Building Environment Garat F. et al. 1999. Guiding and interacting with virtual crowds in real time. 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Emergency guidelines and procedures for employees. CCH Canadian Limited, Canada. Read More