Safety of people in the event of a fire - Introduction to Fire Safety Management - page 241

Detection - is the process of receiving information
from the outside world. The detection process involves
all the sense organs:

The illusion shown in Figure 10.2 is not an inaccurate
perception: it is a demonstration of how one perception
can be inconsistent with another perception. Recognition
of the saxophone player is just as valid as recognition of
the young woman. Both are as real and accurate as one
another. This example also demonstrates that perception
is an active process; humans constantly interpret sensory
data to produce recognisable objects and events.
The problems associated with individual perception
of reality can be further understood by considering the
following key principles in recognition:

➤ Eyes for gathering visual information

➤ Ears for sensing vibrations in the air, including

sound
➤ The nose and tongue are sensitive to certain chem-
ical stimuli

➤ Skin responds to pressure, temperature changes

and various stimuli related to pain
➤ The skeletal structure receptors in our joints, ten-
dons and muscles are sensitive to body movement
and position.

➤ There is a tendency to perceive things as com-

plete, fi lling in the gaps in order to get an overall
impression
➤ There is a tendency to perceive objects as constant
in size, shape, colour, and other qualities

Interpretation - takes place in the brain. The sense
organs send messages to the brain by converting stimuli
from the outside world into nervous impulses.
The brain organises the nervous impulses and inter-
prets these as recognisable information about our surround-
ings such as people, places and events. Recognition and
subsequent behavioural responses to what has been
perceived is affected by internal factors such as the
experience and emotional state of the individual. External
factors such as time or money constraints will also have
a signifi cant impact on how individuals may interpret
information received from their senses.
In order to be able to 'recognise' a situation or
object from data received from the senses, the brain will
attempt to match a set of data to a previous pattern. For
example, a child will learn the look, behaviour, smell and
feel of a dog and subsequently interpret anything that
looks, behaves, smells or feels like a dog as a dog.

➤ Sometimes an object that is constant is perceived

as variable, for example one moment there appears
to be a single object, the next there appears to be
more than one.

It is quite unusual for a person to have experience of
a real fi re or emergency that warrants an immediate
evacuation of a building. The normal experience is
that of a 'false alarm' therefore it is perfectly under-
standable that people, in general, do not perceive a
serious personal threat when they hear a fi re alarm in a
building. There have been instances in fatal fi res when
individuals have failed to perceive the risk of a small
fi re because the rapid growth and movement of a fi re
is outside their previous experience and therefore they
fail to recognise the magnitude of the risk. If a person
underestimates the level of the risk in a fi re emergency,
they are likely to delay evacuation and thereby increase
the risk.

Perception vs reality
Perception varies with individuals, who can interpret
sensory data in a number of ways.

Figure 10.2 Perception can differ

Figure 10.1 Interpreting information