Relationship between human behavioral stage and fire development stage 1

The behavior of people in fires is quite complex. On the one hand, the behavior of personnel has a close relationship with the development stage of fire. In turn, the behavior of personnel can also influence the development of fire to a certain extent.

I. Human behavior stage and fire development stage

The stage of fire development refers to the stable state or situation of fire development in a certain period of time. The earliest proposed fire development stage concept was Professor Lerup of the Planning and Development Research Center of the School of Environmental Design, University of California, USA. He believes that the beginning and end of the fire development phase is marked by "critical phenomena" (such as smoke and flames, etc.). The critical phenomenon is a key point. After this point, the development of fire has changed significantly. For example, the spread of fire in a fire room is in a steady state of development. With the development of the fire, the indoor temperature may exceed 300 °C and cause the glass to break, or suddenly open the doors and windows, and a large amount of fresh air influx will cause "flash fire". After the crash, the fire temperature suddenly rose and the fire entered the next stage of development. "Bulletization" is the critical phenomenon of this transformation and it is the key point of the change.

Human behavior refers to representative key person activities at a specific time. For example, the initial discoverers of the fire, the organizers of the evacuation activities ( including the medical staff of the hospital, the employees of the shops, the leaders of the institutions, and the waiters of the hotel ) , the more prestigious residents among the residents, and the firefighters are representatives of the crowd. The key figure. The behavior of these key figures is consistent with the stages of fire development.

With the in-depth development of fire behavior, researchers have turned their attention to the full performance of people in the fire, that is, a large number of descriptions of research such as what to do, how to do it, who does it, and the sequence of actions to more complex analysis Study the transition to get a typical behavioral pattern and the relationship between the stage of human behavior and the stage of fire development over a period of time. Because human behavior is inseparable from the development stage of fire, with the rapid development of the fire itself, people's behavioral activities are also changing. For example, when there is a fire on the next door or in the vicinity and there is a danger that one’s residence has not yet caught fire but is swallowed up by an instant fire, the rescue of property is the first choice of personnel. When the fire develops to directly threaten one’s own life, the behavior of escape often prevails. Therefore, it is more meaningful to analyze the behavior of people by time period.

Human behavior and fire development can also be seen as a natural phenomenon that accompanies fire development. Any individual is included in a continuous sequence of behaviors. This series of behaviors is called the "behavioral phase." Just as the “critical phenomenon” determines the beginning and the end of the stage of fire development, the behavioral stage is defined by the decision point to determine its beginning and ending. For example, the nurse's life-saving behavior is based on the "decision to go to the rescue" as the starting point, and the decision-making point is terminated by the "decided suspension of rescue" due to heavy smoke. For another example, during the first stage of indoor fire treatment, the decision point was determined by “early discovery of small fire” and the “decrease of fire by breaking through the room” was used as the termination decision point. After passing this decision point, the behavior of the personnel will enter the next stage of behavior.

There is a corresponding connection between the development of fire and human behavior. According to experience and mathematical statistics, there is a mutual restrictive relationship between the behavioral changes of personnel and the development of fires, and not just the causal relationship between fire and humans. On the one hand, human behavior depends on people's reaction to fire, smoke, sound, etc. On the other hand, human behavior also affects the development of fire. For example, after a fire broke out in a hospital, the opening of the ward door to protect the patient in order to save the soil caused the fire to spread to the neighboring room; the door ( window ) that immediately closed the fire room immediately after the initial fire was detected effectively controlled the development of the fire.

Second, the relationship between the stage of personnel behavior and the stage of fire development

The critical phenomena affecting the development of fires are called “key points”, and the “decisive points” affect people’s behavioral changes. Because fires have specific development rules under different conditions, it is difficult to sum up the strict stages of fire development and human behavior. Relationships, but they are consistent in chronological order. The relationship between human and fire in a fire is extremely complicated, so the time that they appear in most cases is not exactly the same, and it is usually determined that the point has hysteresis. In order to understand this relationship in depth, the analysis results of fire development stages and human behavior stages of typical building fires are listed here.

( i ) The relationship between fire development stage and personnel behavior in Georgian apartments

1, Georgian apartment construction

The apartment is a fifteen-storey building constructed in the United States in 1969. It is a reinforced concrete structure. The entire building consists of four parts. The middle of the building is a garden. It forms a ring structure. In the center there are four elevators and a staircase. There are two exits on the floor, and the two wings of the building are connected by a corridor of about 3m wide. The corridor is surrounded by glass windows and each wing has a ladder. There is a basement, 2nd to 15th floor rooms, some suites have balconies. The entire building has a partial fire alarm system with standard fire hydrants.

2 , the development stage of fire

According to the fire and the spread of smoke can be divided into three phases. That is, the fire of the indoor mattress, the smoke from the fire between the suites spread to the entire second floor corridor, and the stage of extinguishing and dispelling the smoke.

(1) Indoor mattress fire stage

The owner of the 214 rooms in the early hours of January 9, about 2:00 back to the room to sleep, because the mattress was awakened about 2:30 overcast ignite the fire. He began to try to drag the mattress to the hallway. He was consciously unconscious and tried to throw the mattress through the window of the balcony, but it was unsuccessful. Moving the mattress back and forth ignited other items in the room, causing air convection between the balcony windows and the door leading to the corridor, contributing to the spread of mattress fire. He left the room to call the police and the fire developed indoors. Hot air and smoke began to spread into the corridor.

(2) Development of fires in suites

About 15 minutes after the owner left the room , that is, when the 2:48 fire brigade arrived, the fire in the suite had developed to a flash fire. During the fire fighting and evacuation of the occupants, the opening of the stairwell door facilitated the proliferation of smoke in the second floor corridor. As the level of smoke spreads, hot air and smoke envelope the entire second floor corridor.

(3) Stages of extinguishing and disperse smoke

Firefighters broke the glass on the second floor near the middle hall in a timely manner. The corridor on the second floor was ventilated, the fire was extinguished, and the visibility on the second floor corridor was improved. The fire caused the fire room 214 to be completely destroyed, and the wall at the entrance of the hallway was also burned through, and individual rooms were damaged to varying degrees. Almost all rooms above the second floor smelled of smoke and were harmed by smoke.

And the fire area is the area of the region surrounded by smoke and flames of fire, smoke normally is confined within the partition, and (or) the partition of the fire. The fire zone may be consistent with the functional units of the building structure and may also break through the functional units. The different stages of fire development are shown in the table below.

3 , the behavior of the staff stage

The behavior of a person in a fire can be based on the stage of fire development and draws a series of consecutive actions into logical paragraphs. This means that the human behavior stage is related to the development stage of fire and smoke. There are also three stages in the behavior of Georgian’s firefighters, as listed in the table below.

The overlap of Phases 2 and 3 is due to the failure of the local alarm system, the identification of different fire timings and the different timing of evacuation.

(1) Treat initial fire

1) The owner of room 214 was awakened by the smoldering fire;

2) Fire extinguishing: Trying to move the fired mattress to the corridor. Consciously wrong, and dragging it to the balcony, without success;

3) When leaving the room, open the window to the balcony and the door to the hallway to call the police. Due to the fact that the person took care of the clothes, the spirit was very tense, and the language of foreigners was unreasonable, the time for the alarm was delayed.

(2) Alarm

1) The firefighters entered the second floor from the central staircase at about 02:48 . They were attacked by hot air and smoke, and the local alarm system was activated for 8 to 10 seconds .

2) The firefighter advised the occupants of the second floor to stay in the room, close the door and open the window, and then take a 50mm hose to extinguish the fire;

3) The occupants explore the fire information in many ways and greet others;

4) The occupants started to escape. According to the survey, 19 people shouted to other people in the fire. Their behavior is shown in the table below. It can be seen from the table that most people's behavior is achieved through personal actions, and only two people are pulling alarms.

(3) Evacuation

In accordance with the arrangements of the fire brigade, evacuation of occupants above the fire floor before the fire was completely extinguished. The occupants of the fire floor ( second floor ) are generally extinguished after the fire is extinguished and the smoke is dispersed. From the above table, it can be seen that there is consistency in the chronological order of the behavioral phase of the fire in the Georgian apartment fire and the fire development phase.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network. To be continued.