View source for ISO/FDIS 9186 Procedures for the development and testing of graphical symbols

==Example Project: Evaluation of Pictograms/Symbols for the trans-european road network==

Due to the complexity of road information in the Trans-European road network, there is a strong need to present information to the driver in a standardized and comprehensible way. Graphical symbols intended to be displayed on variable message signs have been evaluated applying the ISO 9186 standard.

K.Siebenhandl and H.Risku describe that in the comprehensibility judgement test [Siebenhandl and Risku, 2007a] a total of 243 variants were tested during the comprehensibility judgement test for 33 referents. 825 voluntary drivers from Austria, Hungary, Spain, and the Czech Republic participated in the test as respondents. 28 variants reached the threshold for immediate acceptance, 56 were proposed for a redesign. The results provided the pre-selection for next testing phase - comprehension test.

The comprehension test was carried out in Austria, Hungary, and the Czech Republic [Siebenhandl and Risku, 2007b]. A total of 84 variants for the 33 referents were tested on 604 respondents. The test resulted in the recommendation of pictorial symbols for 20 of the referents. The test indicated that more symbolic pictograms (like "City Center" or "Obstacles on the Road") are less likely to be comprehended, than sign containing elemental objects like ("Ferry Boat", or "Deer on Road"). In the report [Siebenhandl and Risku, 2007b] it is recommended, that the symbols with a low ISO score should be advertised to be learned, before displaying them. The results provided the pre-selection for next testing phase comprehension test in impaired visibility conditions.

===Conclusions===

{{quotation|Only after succusfully passing the Comprehension Tests, the pictograms  may be regarded as understandable and worth of employment on the Trans-European Road Network.|[Siebenhandl and Risku, 2007a][Siebenhandl and Risku, 2007b]}}

The example project shows that the comprehensibility of the graphical symbols need to be evaluated in order to know how comprehensive those are, even if designed by professionals. Small changes in design may cause clear differences in the understanding which the designers might not have anticipated and there are also cultural differences. Also the feedback from evaluation can provide the designers valuable input to re-design the graphical symbols, so at its best the test methods are used in close co-operation with designers to allow iterative development of graphical symbols – and improved comprehensibility.