People’s behaviours associated with the fire in the building can be different and affected by the persons’ abilities to hear, see, and recognise the alarm, to understand and interpret the cue, to decide what further actions should be performed, and to act appropriately. The evacuation behavioural model which consists of twenty-six states represents the people’s behaviours in their variety in relation to the mentioned aspects. Twenty-three states can be discussed as the transient states which demonstrate the possible variants of the people’s behaviours after receiving the definite fire cues.
The other three states are used to demonstrate the final stages or results of the evacuation process (S10, S25, S26). However, it is also important to pay attention to such factors as the construction of the building, the number of upstairs, the character of the building population regarding the people’s age and gender, the population’s training, and familiarity with the building. Referring to the personal characteristics, people can choose safe or unsafe variants of evacuation. As a result, 840 routes are possible to be experienced by the building population where 290 routes are unsafe, and they can lead to fatal results.
The pre-movement time includes the time of the people’s recognising and interpreting the alarm or cue which leads to choosing a certain route. The first state is the fire outbreak (S1) about which people learn the information with the help of the warning of fire (S2) or such cues as the flickering light (S3). The next action is the attempt to investigate more information about the fire (S4). The character of the reaction to the initial fire cues affects the further interpretation and choosing the appropriate variant of actions. The misinterpretation of information can result in ignoring the cues and lead directly to making the unsafe decision (S10) or to relying on the more informative or stronger cues (S7, S8, S9). The effective response to the cue after interpreting it (S5) is seeking more information in order to choose the appropriate variant for evacuation (S13).
The investigation of the fire aspects should result in trying to overcome the situation and find the problem solution. Nevertheless, the previous intention to act can provoke a range of different behaviours such as the collection of belongings (S12), attempts to fight the fire (S14), and attempts to warn the others (S16). Thus, the reactions depend on the people’s training and perception of the situation. The perception of the situation and its interpretation can be relevant or untrue. If people effectively interpreted the situation, received the definite, and instructed the other persons, they can evacuate successfully following the instructions (S19). Before evacuating, people can experience some difficulties with interpreting the situation and finding the right decision. Thus, their pre-movement time can become longer because they wait for help or assist other people (S15), evaluate paths (S20), and move along the egress routes (S21). From this point, the mentioned states represent the recurrent actions of individuals which can finally lead to the assessment of the egress routes (S22). The other actions of people depend on the correctness of the assessment. People can have ambiguous information or their assessment can be inadequate. That is why people can choose the irrational variants for evacuation based on their panic behaviours or inadequate assessment.
The choice of routes depends on the assessment of their quality (S22). The number of egress routes (stairways) also influences the effectiveness of the evacuation operation. People are often inclined to choose routes that are not relevant in this situation but are familiar to them. As a result, the situation can lead to choosing an alternative route (S24). It is also important to pay attention to the fact that the number of available routes decreases with the spread of the fire. If an individual chooses the untenable route, he or she can choose the alternative path (S24) or follow this route which can lead to fatalities (S26). States 22 and 24 are recurrent, and the most effective choice leads to focusing on the tenable egress route (S23) which guarantees effective evacuation (S25).
Focusing on the range of people’s evacuation behaviours which can be irrational or correct, it is necessary to determine the required safe egress time based on all the people’s possible reactions to the fire alarms and fire cues with their further interpretation. In building fires, the interpretation of the fire alarm or fire cue affects the people’s perception of the situation and decision-making process to choose the route for evacuation. The most effective possible variant is the situation of reaching a place of safety. Nevertheless, it is necessary to refer to the sequences of the important factors which affect further behaviours. Thus, the interpretation of the cue is based on its recognition (light, sound, and odour). The correctness of the interpretation leads to an accurate decision-making process. The analysis of all the cues and the correct decision-making process should result in an effective evacuation for the building.