whereas those who know that the fire is close by, may feel a heightened threat to their safety and may panic and feel the need to escape as quickly as possible, leading to stampedes and crush injuries. Sensory Perception Humans have five senses or types of sensory perception, these five senses are touch, taste, sight, smell, and hearing. The senses make it possible for people to interact with others and get around in their daily lives. In an earlier section, we covered methods of assisting persons who are visually and hearing (sensory) impaired to respond to evacuation alarms along with other persons, and whilst seeing and hearing still remain a relevant aspect, also smell and touch have high importance to people in the sensory perception of fire and its detection. It is not uncommon that evidence of combustion and pre-combustion are detected by the sense of smell prior to any automated detection system. This can be particularly true of slow burning materials, more so in a concealed area or cavity. Materials also often give off characteristic 'smouldering smells' when exposed to a heat source prior to the actual ignition and combustion of the material. This is not to suggest that only smell should be relied upon to detect fire, however, many fire procedures and policies will refer to raising an alarm if smoke or burning can be smelt. The touch sense can also be utilised as a detection method of fire by the sensing of heat through a structure or a wall. (Please consider the methods of heat transference in the case of fire). A simple but effective method taught to detect fire from the outside of a closed room is to carefully place the back of a hand against the door to check for a level of heat. In this instance, sensory perception is being used directly to check for the effects of fire. In conclusion, sensory perception can then have a significant role in the detection of fire, and in the instance of premises without other means obviously becomes the singular method of detection, this said given its potential human flaws it must never be solely relied upon as the means of detection. The Recognition of Fire Threat, Perception Versus Reality Fire risk assessment must consider occupants and their expected actions and reactions. Visitors to a building will be more passive during an emergency than residents or employees. Because they are unfamiliar with a building under normal conditions, visitors are likely to spend more time on threat recognition and validation. Occupants will turn to supervisors and others in authority for instruction. The majority of people both understand the risk and potential for injury or death from fire, in particular if they consider that 'they are trapped' in a burning building. In this type of situation, the potential for fear to turn to panic is high, however such panic does not have to stem from an actual level of threat. Panic can occur even if the person only perceives that danger exists from the fire and is about to overtake them. The reality of the situation is that the source of the fire is of a sufficient distance away not to pose a significant threat for a long period. Conversely after an occupant senses and understands an alert or alarm signal, or identifies another fire cue (such as heat, flame, or smoke), the next step is a process of interpreting this information and deciding if the alarm or fire cue is a real threat to themselves.
©SHEilds – All rights reserved FCV 4 JUN 2021
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