Amazingly; most literature on application of warning signs usually only deals with standardising shapes; size and symbols of warning signs in different contexts (compare (Executive; 1996; mekanstandardisering; 1984; Meeting; 1991). Not much work has been done evaluating how and in which way warning signs have an impact on human psyche.
A warning is an artefact. Its purpose is to evoke a suitable reaction of human beings in a certain context. This is achieved by creating a connection between the warning e.g. an abstract sign or sound signal (Edworthy and A.; 1995) and its referent (Easterby and Zwanga; 1984). The referent is a product or objective situation which under certain circumstances can be hazardous to human beings.
The warning itself has two different aspects; an iconic aspect and an informational aspect which together trigger an appropriate action. The informational aspect can be a symbol or text. The iconic aspect can be the shape; colour; symbols etc. In contrast to the informational aspect; the iconic aspect needs to be mapped and interpreted. From this information the degree of urgency is then derived.
A warning sign consists of a carrier have a certain colour or combination of different colours and a shape. Reserach shows that certain colours and combinations of colours do have an affective impact on the human mind (Edworthy and Adams; 1996). In nature; yellow/black can be found on insects siganlizing danger. Also red and orange colours are considered to do so (Edworthy and Adams; 1996). Hence those colours are preferred colours for displays or e.g.painting dangerous machines or parts of them.
Commonly; also symbols are used in order diversify the way the danger can apply. These symbols can either be descriptive (i.e. describing the hazard); prescriptive (i.e. explaining suitable behaviour) or proscriptive (i.e. forbidding certain behaviour) (Easterby and Hankeil; 1977). However these symbols does probably possess no or low emotional effect. Correct interpretation requires prior knowledge and a similar social context.
Keywords: Warning sign; Affective Engineering; Affective Meaning