Pre-evacuation Time Research Articles

A Post-fire Survey on the Pre-evacuation Human Behavior

A delay in the pre-evacuation reaction may be one of the reasons causing occupants to be ‘trapped’ in a dangerous zone. Under fire situations, people are found to behave differently in that some may start evacuation immediately, some may ignore the fire alarms and engage in their activities and some others may participate in fighting the fire. These behavioral reaction patterns are influenced by some factors, such as occupant characteristics, building characteristics and fire characteristics. The purpose of this study is to investigate the pre-evacuation behavior of occupants under fire and explore the associations between these factors and the human behavior. To obtain the human behavioral information in real fire, a post-fire survey for a multi-storey office building fire in a major city in Mainland China was carried out with the assistance of local fire professionals. Some of the possible factors that might influence the occupants’ actions at recognitions and response stage were examined. It was reckoned that the behavioral reaction at recognition and response stage was mainly dependent on the human characteristics and building characteristics except the fire characteristics. The results also implied that pre-evacuation time was typically influenced by the occupant characteristics.

Application of Code Approach for Emergency Evacuation in a Rail Station

This paper presents an emergency evacuation analysis during a mid-platform train fire in an underground rail station. A time-based evacuation scenario is developed taking into account the stairway inaccessibility due to smoke blockage. The calculation approach in NFPA 130 is then applied to a parametric study of this time-based scenario and its reliability is examined using a micro-simulation model. Both methods give consistent predictions of the exiting times. The results demonstrate that with the division of the station into two zones, the exiting time could not meet the code requirements, whereas it does meet the required exiting time without the division. Such division is due to smoke blockage and creates an uneven ratio of the occupant load to the available exiting capacity. This shows that appropriate consideration of the fire and smoke effects is important for station egress evaluation. Other issues such as the fire growth rate and the pre-evacuation time are also discussed.

Simulation study on the effect of pre-evacuation time and exit width on evacuation

Occupant pre-evacuation time is often oversimplified into an explicit value in evacuation calculation. In fact, it is not an explicit value but a random variable following some kind of probability distribution. In order to analyze the importance of pre-evacuation time in evacuation calculation, Grid- Flow evacuation model is utilized to study the effect of pre-evacuation time on evacuation under different occupant densities and exit widths in a single room scenario. The evacuation time calculated by using normal pre-evacuation distribution is compared with that calculated by explicit pre-evacuation time. Two faults are presented when pre-evacuation time is considered as an explicit value. The theory of con- gestion and queue is presented to analyze the cal- culation results. Moreover, this paper also presents probability distribution of the total evacuation time when the pre-evacuation time follows normal distri- bution. The results show that the evacuation time is dominated by pre-evacuation time and hardly de- pendent on occupant density when the mean pre- evacuation time is long. For long mean pre-evacua- tion time, low occupant density or wide exit, when pre-evacuation time follows normal distribution, the total evacuation time also follows normal distribution.

Collection and Analysis of Pre-Evacuation Time Data Collected from Evacuation Trials Conducted in Library Facilities in Brazil

Two evacuation trials were conducted within Brazilian library facilities by FSEG staff in January 2005. These trials represent one of the first such trials conducted in Brazil. The purpose of these evacuation trials was to collect pre-evacuation time data from a population with a cultural background different to that found in western Europe. In total some 34 pre-evacuation times were collected from the experiments and these ranged from 5 to 98 seconds with a mean pre-evacuation time of 46.7 seconds

The Effect of Pre-evacuation on Evacuation Times in the Simulex Model

The evacuation time of a building in an emergency can be broken down into a number of constituent times including the pre-evacuation time and the travel time. This paper examines how distributions of pre-evacuation times affect the occupant travel time and hence their effect on the evacuation time in the Simulex model. A simple scenario is assessed mathematically and compared with the results from Simulex with further simulations carried out on a somewhat more complex scenario. Because we expect the pre-evacuation time to be characterized by a distribution of values, simply adding the maximum pre-evacuation time and the movement time over-estimates the evacuation time. Furthermore, when the preevacuation distribution is small the travelling and queuing effects dominate the simulated evacuation time. When the pre-evacuation distribution is large, then travel and queuing effects are not so important and it is the pre-evacuation time that dominates. Finally, the paper examines some aspects of the Simulex model in situations where there is a high occupant density in a space.

The Collection and Analysis of Pre-evacuation Times Derived from Evacuation Trials and Their Application to Evacuation Modelling

This paper presents data relating to occupant pre-evacuation times from university and hospital outpatient facilities. Although the two occupancies are entirely different, they do employ relatively similar procedures: members of staff sweep areas to encourage individuals to evacuate.However the manner in which the dependent population reacts to these procedures is quite different. In the hospital case, the patients only evacuated once a member of the nursing staff had instructed them to do so, while in the university evacuation, the students were less dependent upon the actions of the staff, with over 50% of them evacuating with no prior prompting. In addition, the student pre-evacuation time was found to be dependent on their level of engagement in various activities.

The Collection Of Pre-Evacuation Times From Evacuation Trials Involving A Hospital Outpatient Area And A University Library Facility

This paper presents data relating to occupant pre-evacuation times from a university and a hospital outpatient facility. Although the two structures are entirely different they do employ relatively similar procedures: members of staff sweeping areas of the structure to encourage individuals to evacuate. However, the manner in which the dependent population reacts to these procedures is quite different. In the hospital case the patients only evacuated once a member of the nursing staff had instructed them to do so while in the university evacuation the students were less dependent upon the actions of the staff with over 50% of them evacuating with no prior prompting. Although this data may be useful in a variety of areas, it was collected primarily for use within evacuation models.

506 光電子分光法による摩擦材表面の化学状態解析(OS.5 摩擦振動)

Several experimental problems in order to apply x-ray photoelectron spectroscopy for the analysis of surface chemical states of friction materials were examined. It has been revealed that the spectroscopic method can be successfully applied if the sample sizes were chosen to be small enough and pre-evacuation time for them were long enough to maintain a ultra-high vacuum during data acquisition. Data acquired show that they have enough energy resolution to analyze various changes of the chemical states due to friction tests.