Measures of sign effectiveness

 MEASURES OF SIGN EFFECTIVENESS

• Traffic signs are constantly evaluated for their effectiveness in preventing accidents with other vehicles, pedestrians and infrastructure (Government or private property).
• Evaluations are done based on field observation of pedestrian and driver behaviour before and after installation of countermeasures at specific locations selected on the basis of frequency of accidents observed. 
• A statistically significant improvement has been reported in case of driver behaviour and pedestrian habits at locations wherever such countermeasures were adopted.
• Signs and markings are used to control and guide traffic and to promote road safety.
• The quality of its traffic signs and markings make a significant contribution to road safety.
• To be effective, signs and markings must be designed and implemented in a way that the messages they convey are clear, unambiguous, visible and legible. 
• At the same time these should give warning to drivers and road users with sufficient time to respond safely. 
• Maintenance of signs and markings is important. 
• Distraction can also be caused by looking for a sign that may be missing. Therefore, continuity of directional signing is important. Young (age 17-21) drivers are particularly prone to external-to-vehicle driver distraction caused by signs. 
• New generations of traffic signs based on electronic displays can also change their text (or symbols) to provide for "intelligent control" linked to automated traffic sensors
• Real-time Traffic Message Channel incident warnings are conveyed directly to vehicle navigation systems using signals carried via FM radio, 3G cellular data and satellite broadcasts
• Confusion of drivers, misunderstanding or lack of familiarity with traffic control devices can lead to accidents
• It has been demonstrated that supplemental 'text' information along with a symbol has shown a marked improvement over usage of only symbols
• Replacement of existing signs with signs that are easier to understand improves the effectiveness of signs. This is done by evaluating the drivers response to an accident prone area with a particular sign.
• Driver education and driver improvement programs are positive predictors of knowledge of traffic controls.
• Effectiveness of traffic signs should be directed towards the driving public by making use of public service announcements and educational campaigns.
• The effectiveness of a traffic control to a large extent depends on conspicuity as determined by brightness contrast, primarily the similarity of the control device relative to its surroundings.
• The probability of seeing a traffic sign or pavement marking is lessened with increased experience in driving, and each type of sign has a specific rate of decline.
• Signal value is determined by the probability of punishment for disobedience of the traffic control. 
• Speed limit signs have been found to have a high signal value, which is a result of the motorist's awareness of constant enforcement efforts. 
• Other signs which are less frequently enforced would be expected to have a lower signal value, in spite of the fact that violation of these signs may prove more hazardous.
• Level of exposure refers to the number of times the driver has read the communication before.
• Length of exposure refers to the viewing time of the recipient.
• Both level and length of exposure are salient variables affecting the motorist 1 s information processing capability.
• In daily situations, many motorists simply "ride with the tide" of traffic or stay in the traffic flow, unable to independently navigate the roadway.
• Education regarding traffic controls, in the form of driver education, defensive driving, and informal education, has a direct effect on correct identification of traffic signs.
• Understanding of specific signs has been found to be a function of education level, driving experience, driver education, age, and several other factors
• It has been proved by field studies that drivers with the highest level of understanding had taken a driver education course
• The STOP sign is not as widely recognized as would be expected by its unique shape and color. The word 'stop' must be visible on the sign to be identified by the driving population
• Similarly, was the case for "YIELD" and "DO NOT ENTER" signs. Hence, it is imperative to write TEXT along with the symbol.