The Department for Transport (DfT) commissioned AECOM to undertake a study to explore road user awareness and understanding regarding the meaning of a number of traffic signs and identify any areas for improvement. Overall 38 signs were specified, by DfT, for inclusion in this project. All signs were shown to respondents in the context of how they would usually be seen on the road network. All but one of the signs were shown in a static presentation. For each sign respondents were shown a large picture of the sign itself and a photograph depicting a scenario where that sign would usually be seen. Seven signs were shown dynamically whereby a simulation of a driving experience was created which included the sign under consideration. The video clips were designed so each sign would be seen by respondents for a couple of seconds reflecting how long a person travelling at 30 miles an hour would realistically have to take in all the information given on the sign. The first stage of the study involved depth interviews with members of the public and stakeholders in order to get views on the traffic signs being considered and to get feedback on the proposed method for undertaking the survey which used computers to show the signs to respondents both statically and dynamically. Also cognitive interviews were carried out to test peoples’ understanding of what they were being asked in the survey. This showed that people are able to read the words on the sign and feel that it was easy to understand. However when asked what the sign allowed them to do, they became less confident. Consequently rather than just using peoples’ unprompted comments to get an understanding of what the sign meant, which can be difficult to interpret accurately, this study used a number of comprehension questions to test people’s actual understanding of what the sign meant. We believe this more robust approach gives a far better guide to whether people understand traffic signs. The second stage of the study involved a large scale household survey. Between 15th and 28th January 2011, 820 people were interviewed across England. Respondents represented a range of road users. For Each Sign: respondents were asked: - Their understanding of the sign (unprompted) by recording verbatim what they understood the sign to mean. - A series of comprehension questions to further test whether respondents fully understood the sign and were not just ‘reading’ what was written on the sign. - After being told by the interviewer what the sign actually meant, respondents were then asked to bear in mind the answers they gave and the meaning of the sign, how easy or difficult they found it to understand. - Whether they thought the sign could be improved, and if so, how? The table below summarises the key areas of understanding and miss-understanding for each sign. It also provides some suggestions for improvement. There were few significant differences in understanding for different types of people. In the context of sign clutter, a minority thought there were too many road signs. A quarter thought there were too many road signs on main roads, One in five thought there were too many on local roads. This study has shown that the overall meanings of the signs under consideration were generally understood. It also showed a good basic level of understanding as to what different types of traffic sign meant. Nine out of ten knew a red triangle sign gave a warning, seven out of ten knew a blue circular sign gave a positive instruction and six out of ten knew a red circular sign was forbidding an action. However, respondents were often confused with the unwritten information. For example, on parking signs where a sign shows times of restrictions, there tends to be uncertainty about what is permitted outside those hours. Where a sign relates to assess such as ‘no vehicles’ or pedestrian zones there is less certainty about whether cyclists are or not allowed. Respondents had most difficultly where signs showed several pieces of information such as parking signs which show restrictions for no waiting, no loading and parking. Respondents would find it difficult to take in all the information and therefore be unsure as to the appropriate behaviour. When viewed dynamically the amount of information respondents were able to take in was small; respondents could take in the main message for example; bus lane but they were unable to take in the times of operation. The symbol for ‘no waiting’ was not easily recognised by respondents and they also regularly used the terms ‘no waiting, ‘no stopping’ and ‘no parking’ interchangeably. Some prohibitive signs (red circle signs) such as ‘no vehicles’ and ‘no pedestrians’ were shown to respondents with and without a bar across. Although the addition of the bar increases understanding, the level of understanding was already extremely high (around 80%). The table below provides an overview of the main findings of the research. The conclusions have been drawn from several areas including verbatim comments, the response given to the comprehension questions and the in depth interviews and therefore an exact statistic cannot always be provided. Where it is possible, the proportion of people answering correctly has been specified. (Author/publisher)
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