**1. Introduction**

Road transport is the most common transportation form globally. Road transportation provides benefits both to nations and to individuals by facilitating the movement of goods and people. It enables increased access to jobs, economic markets, education, recreation, and health care, which in turn have direct and indirect positive impacts on the health of populations [1]. However, driving on roads is a complex task that involves extensive interactions between road users and the other components of the transport system, such as the driver, the vehicle, and the road traffic environment [2]. This interaction, if well-coordinated with appropriate road signs, effective drivers' road sign education and comprehension, can result in smooth flow of traffic, enhanced road safety and a general reduction in traffic violations and accidents [3]. However, it has been reported that over 1.2 million deaths and about 50 million non-fatal injuries result from road accidents globally on an annual basis [1]. The global cost of road accidents has been estimated to cost the world economy USD 1.8 trillion between 2015–2030 or 0.12% of global Gross Domestic Product [4]. In a bid to reduce this number of deaths, governments around the world are taking different measures depending on the local domestic characteristics and driving behaviors they wish to stop or encourage. Researchers have also undertaken assisting governments by assessing the relationships between various factors and driving safety on roads. Governments respond to bad driving behaviors mostly through punitive measures such as fines to curb bad driving practices. Others have suggested the standardization

**Citation:** Al-Rousan, T.M.; Umar, A.A. Assessment of Traffic Sign Comprehension Levels among Drivers in the Emirate of Abu Dhabi, UAE. *Infrastructures* **2021**, *6*, 122. https://doi.org/10.3390/ cinfrastructures6090122

Academic Editors: Krzysztof Goniewicz, Robert Czerski and Marek Kustra

Received: 30 July 2021 Accepted: 30 August 2021 Published: 31 August 2021

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**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

of traffic signs internationally to enhance the ability of tourists to drive without further host-country training [5].

The roads in the United Arab Emirates (UAE) are some of the best in the world in terms of quality, as evidenced by their ranking in the road quality index. The UAE roads were ranked ahead of more developed countries such as Germany, USA, UK and France in the 2019 report of the World Economic Forum [6]. Oil wealth has led to the rapid growth and development of Abu Dhabi and its sister Emirates within the UAE arrangement. This rapid economic growth has attracted people from different regions of the world to the UAE with its attendant need for smooth and efficient means of transportation. A large volume of tourists also frequents the UAE annually, reaching over 15 million tourists in 2018 [7]. Some of these tourists prefer to rent cars and drive around on their own in order to get a better feel of the country. While the Emirate of Dubai has introduced the Dubai metro in addition to other modes of public transportation, the Emirate of Abu Dhabi only relies on public buses, taxis, rental cars and private cars for the movement of people. This has led to pressure on residents to own a personal car to ease movements from point to point. With so many drivers from diverse backgrounds and driving educations, the situation is ripe for traffic violations and accidents.

The police in Abu Dhabi issued five million fines against drivers in 2019 [8], with a population of about 2.9 million (2016 estimates from Statistics Centre of Abu Dhabi (SCAD)); this translates to 1.7 fines for every resident. Despite the increased volume of fines against drivers, it has been found that road traffic injuries in the UAE remained stable from 2012 to 2016 [9]. Another alarming factor in the road injuries and fatalities is the overrepresentation of UAE nationals among the fatalities and the injured [10]. One study of five countries within the Gulf Co-operation Council (GCC) found that the drivers correctly comprehended only 56% of the traffic signs they were presented [11]. The authors also found that for the UAE in particular, the respondents (N-861) correctly comprehend only 62% of the traffic signs presented to them. They attribute the poor performance to the manner in which drivers are licensed and the laxity of the assessments. Similar studies carried out in the United States by Ward et al. [12] also found that drivers could not comprehend a large percentage of the international road signs they were presented. In Turkey, Yakut [13] found that on average, participants correctly identified 81% of the signs presented. In Kano city, Nigeria, it was found that the average traffic sign comprehension level was as high as 79%, with the least comprehension being 54.7% on the "Park and Ride" sign. However, they found that truck drivers had a lower understanding level than all other classes of road users [14]. A study of drivers' sign comprehension across four countries (Poland, Finland, Canada and Israel) found that on average the drivers identified 58.5% of the signs correctly [5]. This goes to show that the problem is not limited to developing countries only, developed countries are also struggling.

A recent study of road crashes in Abu Dhabi between 2012 and 2017 revealed that there were 1.26 million crashes, 9327 injuries, and 1305 fatalities during the period covered. The study went on to reveal that the crashes tended to be fatal when collisions occurred between 22:00 and 5:59 o'clock, occurred under adverse weather conditions, involved pedestrians or drunk drivers, occurred on higher speed limit highways, as well as when drivers were male, minors and/or Emiratis [10]. The economic costs of these accidents to the GCC have been estimated to be around \$7.5 billion annually [15]. While the police attempt to use fines to correct poor driving behaviors, governments, on the other hand, focus on road improvement projects. Little attention has been paid by governments in assessing drivers' knowledge and comprehension of traffic signs, which facilitates and enhances safety and better road use compliance. The situation is further compounded due to today's travel culture where people are often licensed in one country and then drive without any further training or assessments in another country [5]. This happens to be the case across the GCC where Americans and Europeans seldom undergo any assessments but are issued licenses upon presenting their home-country drivers' licenses. A good understanding of traffic signs assists drivers in proper use of roads, contributes to the

smooth flow of traffic and enhances safety. Therefore, this study seeks to assess the level of road traffic signs comprehension among drivers in the Emirate of Abu Dhabi.

#### **2. Literature Review**

Road traffic signs help regulate traffic, provide crucial visual guidance, can alert drivers to potential hazards on the road and give drivers important preview time during night-time conditions [16]. In addition, well placed and maintained traffic signs provide drivers with clear guidance that enables them to act in a timely manner in accordance with the displayed instruction. Poorly maintained and illegible road signs can cause travelling delays and increase the potential for accidents for road users, especially drivers using such roads for the first time. Poorly maintained road signs are a growing problem even in developed countries. For instance, European Union Road Federation (ERF) [16] reported that 33% of Germany's 25 million road signs are considered non-readable, while another 25% are older than 15 years. Traffic signs come in both text and symbols, while in some instances may be text alone or a symbol alone. Researchers have assessed which option is more effective in delivering the required message to drivers. While it was found that text signs were difficult to comprehend by tourist respondents in Thailand [17], in Israel, a combination of text and symbols was found to be more acceptable and reduced driver comprehension time [18].

Past studies have also found that personal and social factors significantly affect drivers' comprehension of road signs [5,11,17,19,20]. In the case of Al-Madani and Al-Janahi [11], in their comparison of the countries within the GCC, they found that the drivers' education level, income range and nationality affected their ability to correctly identify traffic signs. Interestingly, they also found that males had a better comprehension than females and western drivers performed better than their Arab counterparts did. In Thailand, Choocharukul and Sriroongvikrai [17] assessed tourists in the country and found that drivers' age, experience in a foreign land and their nationality had a significant impact on ability to comprehend and translate road traffic signs. In the case of Shinar et al. [5] who assessed comprehension across four countries (Canada, Finland, Israel and Poland), they found that the age, gender and country (nationality) all had a significant impact on the comprehension levels of the respondents.

Taamneh and Alkheder [20], in their study of Jordanian drivers, found that only 61% of the drivers comprehended regulatory signs, 66% of drivers comprehended warning signs and 75% of drivers comprehended guidance traffic signs. They also found higher comprehension levels among drivers holding a commercial driving license and drivers with driving experience of more than 11 years.

Kirmizioglu and Tuydes-Yaman [21], in their study in Ankara-Turkey, found that out of 39 signs, only 12 were recognized correctly by almost 70% of the participants. They further found that over 10% of the drivers comprehended five of the signs oppositely, and they argued that the implication of this was riskier than not knowing at all. In Iraq, Ismail [19] found that drivers' comprehension of traffic signs increased with increasing education levels, the urbanization level of his residence and daily driving practice. Males and private car drivers were found to have a higher comprehension than females and other driver categories, respectively. He also found that marital status had no significant effect on the comprehension level of drivers. Ou and Liu [3] studied the influence of sign design features and training on the comprehension of 65 selected Taiwanese traffic signs on Taiwanese and Vietnamese drivers. They found that training outcome was positive in both user groups. The average comprehension improved from 0.63 and 0.41 pre-training to 0.98 and 0.89 post-training for Taiwanese and Vietnamese drivers, respectively. More importantly, comprehension scores measured after one month remained higher than pre-training.

Traffic signs are a simple and cost-effective intervention that can yield impressive rates of return in terms of road safety, and thus reducing the socio-economic consequences [16]. The European Union Roads Federation's review revealed that having good signage reduced fatalities by up to 87% in the UK. In Norway, the value derived from improved traffic

signs was found to outweigh the costs by a factor of 3.5:1 [22]. While in Australia, its National Black Spot program was estimated to have reduced fatal and casualty crashes at the treated sites by 30%; the report went on to reveal that traffic sign interventions had the best cost-benefit ratio, ranging between 15:1 and 20:1 depending on the financial hypothesis made on the project [23].
