Improving Road Safety with Effective Road Traffic Signs

Slides:



Advertisements
Similar presentations
FHM TRAINING TOOLS This training presentation is part of FHMs commitment to creating and keeping safe workplaces. Be sure to check out all the training.
Advertisements

* 07/16/96 Guide Sign Design June 18-19, 2013 Arden Hills, MN *
How would you like it if people drove their cars thru your office?
Revisions to Chapter 2B – Regulatory Signs, Barricades, and Gates.
M3 - 1 The Road to Skilled Driving April 2006 Chapter 2 Signs, Signals and Roadway Markings.
Signs, Signals, and Roadway Markings
Traffic Controls Lesson 1 Understanding Traffic Signs and Signals
Traffic Signs The general principle of traffic signs is to make a message known quickly, (70mph) accurately, with minimum reading skills required. This.
Rules of the Road. Introduction This training will assist Spanish- speaking Motor Carriers in understanding some of the important traffic regulations.
Traffic Controls Lesson 1 Understanding Traffic Signs and Signals
Overview of 2009 MUTCD. Tom McDonald, PE Safety Circuit Rider Iowa LTAP.
Driver Safety.
2009 MUTCD (Final Rule) Revisions Incorporated into the 2009 MUTCD Revisions to Chapter 2B – Regulatory Signs, Barricades, and Gates.
HERO UNIT Training Module Work Zone Traffic Control And Incident Management Operations.
Lesson 6 Traffic Safety Protecting People While Stabilizing The Incident.
Lec 25, Ch.7, pp : Intersection types and design principles (Objectives) Become familiar with the typical intersection types (See figures 7-1 thorugh.
Road Safety Audits Ghazwan al-Haji PhD student ”On whats goes wrong in road design and how to put it right safely”
Lec 14, Ch.8, pp : Intersection control and warrants (objectives) Know the purpose of traffic control Know what MUTCD is and what’s in it Know what.
Lec 3: Ch 3, Part I User and Vehicle Characteristics Objectives Know five critical components of the traffic system Know there is considerable variability.
Work Zone Safety It Starts With YOU!!. 2 BOOK 7 What is NEW??? IMSA TECHNICAL EXPO October, 2014 Dave Edwards.
Traffic Engineering Traffic Control Devices. Traffic Control Traffic engineers do not have any control over individual drivers need to develop devices.
Driver Safety Fall 2014 Miss Padelsky. Traffic Signs, Signals & Road Markings  Traffic signs, signals & road markings are set up to control the flow.
Guidelines for Traffic Control at Surface Mines
© 3M All Rights Reserved. Peter Pape, European Technical Manager 3M Deutschland GmbH Traffic Safety Systems Laboratory.
Chapter 2 Signs, Signals, and Roadway Markings
Office of Traffic, Safety and Technology Guide Sign Design June 17-18, 2015 Arden Hills, MN.
DRIVER SAFETY.
Virginia Learner’s Permit
Signs, Signals and Pavement Markings
Transportation Engineering Lecture 1: Introduction Dr. Bidisha Ghosh
Characteristics of an Expressway Brandon Dye Wednesday October 24, 2007.
Office of Traffic, Safety, and Operations Application Guidelines Warning Signs Signing Plan Design (At-Grade) June 20, 2012.
Office of Traffic, Safety and Technology Chapter 2 Signing Overview Traffic Signs 101 November 20, 2014.
Getting a Probationary Licencse…  Must pass MVC’s Knowledge and Vision tests  Complete Six months of supervised driving  Must be at least 17 years old.
1 Development of countermeasures Hossein Naraghi CE 590 Special Topics Safety March 2003 Time Spent: 6 hrs.
TRENDS AND HIGHWAY CLASSIFICATIONS Spring Examples of highway design problems
Highways and Airports Engineering Project Lecture 2 Highway Signs and Markings Cairo University Faculty of Engineering Public Works Department Dr. Dalia.
The New Jersey Driver Manual
Minimum Sign Retroreflectivity Requirements Updated August 2012 with compliance date revisions.
MUTCD KEY Concepts for Traffic Control Applications.
Presented by Keenline Innovation Technology & Training Inc.
Road Ranger / TMC Operator Joint Training Module 101 MODULE 10 MODULE 10 Road Ranger Work Zones.
2003 MUTCD Chapter 2A Signs General. 2A.06 Design of Signs  Add to the support statement “General appearance” of sign legends, colors, and sizes shown.
Understanding Work Zones
Donald E. Howe, P.E. Division of Traffic Operations California Department of Transportation Minimum Sign Retroreflectivity Requirements New.
On The Highway We’ve Got Your Back 2007 Safety Stand down Responding to and working at roadway incidents Ready to Respond.
 SIGN, SIGNALS, & ROADWAY MARKINGS Do Now - Create a list with as many different road signs you are able to think of. What does each sign tell you? Classify.
Unit 2: Signs, Signals, and Roadway Markings
ROADWAY MARKINGS A roadway marking gives a warning or direction. Roadway markings are usually lines, words, or symbols painted on the roadway. Some markings.
Construction zones and traffic control Objective Review extent of problem Identify contractor responsibilites Identify control plan components.
Idaho Public Driver Education Signs, Signals, & Roadway Markings.
Lesson Plan For Day Two Power point presentation 30 min Video– AAA- signs, signals, etc. 20 min Quiz- Signs Etc 10 min Correct 10 min H/O- Signs 10 min.
Chapter 2 Signs, Signals, and Roadway Markings Start working on the Start working on the 8 questions on page 39! 8 questions on page 39!
5/8/02FHWA Office of Safety1 Funding Resources for Highway Safety (FY2001 Fed-Aid) $1.4 $5.6 Min. Guarantee Bridge Surface Transp. Program National Hwy.
Module 3: Topics 1-3 Vision and Driving
Montana Driver Education and Training Traffic Control Devices and
Signs, Signs, Everywhere Signs
Chapter 3 Regulatory, Warning & Guide Signs Overview
Traffic Control Devices
Signs, Signals, Markings & Speed Limits
The Highway Transportation System. (HTS)
Chapter 3 Regulatory, Warning & Guide Signs Overview
Signs, Signals and Roadway Markings
HERO UNIT Training Module
Traffic Control Plan A plan directed to the safe and expeditious movement of traffic through construction and to the safety of the work force performing.
Example of cones and signs as traffic control at a roadway incident.
Rules of the Road Chapter 10
Minimum Sign Retroreflectivity Requirements Updated August 2012 with compliance date revisions New Retroreflectivity standards were added to the MUTCD.
Safety Benchmarks Best Practices Roadway Incident Scene Safety
Presentation transcript:

Improving Road Safety with Effective Road Traffic Signs When travelling at high speed, drivers expect to be able to detect / identify and understand messages provided to them by road signs easily and in time to make whatever maneuver is required. Scientific observations worldwide show that in reality these requirements are not always met and the consequence is that many road accidents are the direct or indirect result of poorly maintained, inadequate traffic signs.

Program Current Situation & Trends Legal & SANS Overview Science of Sign Sheeting Technology Key Points & Recommendations In the program we will review the current situation and trends, discuss the regulations, SANS standards and Traffic Signs Manual requirements for Road Traffic Signs, review the current available reflective sheeting technology used on road traffic signs, look at some driver needs in terms of reflective performance and summarise with some key points and recommendations.

Current Roadway Situation 1939 Increasing Vehicle population Kilometers travelled Heavy Truck Traffic Vulnerable Road Users (Pedestrians/Cyclists) Congestion Complexity Today Today's situation is much different from the early days of road transport Mobility is key in today’s society, as supported by continued growth in vehicle population, kilometers traveled and an increase in pedestrian and bicycle activity Traffic volume continues to increase steadily and also the level of motorization The projection is for this trend to continue. This, combined with the changing mix of drivers results in further increases in complexity Increased motorization is especially critical for developing countries, as they will need to be prepared to safely handle the increase in exposure. Source: OECD Vulnerable Road User Report

Source: Elizabeth Kopits and Maureen Cropper Road Safety Situation – Fatality Projection World Bank Region % change 2000 - 2020 South Asia 143.9% East Asia & Pacific 79.8% Sub-Saharan Africa Middle East & North Africa 67.5% Latin America & Caribbean 48.1% Europe & Central Asia 18.2% Sub-total 83.3% High-income countries - 27.8% Global total 66.4% Fatalities are expected to increase 66% between 2000 & 2020 overall with high increase projections in the developing world and decreases in high-income countries. Asia has the high percentage of the world-wide traffic fatalities today and also the highest increase projected. If we look at the road safety situation in terms of fatalities as a ratio to kilometers travelled, we know that developed countries have better statistics, due to: Developed infrastructure Perhaps better enforcement More modern vehicles Source: Elizabeth Kopits and Maureen Cropper

Road Safety Situation - Nighttime Accidents & Fatalities Lets look at when accidents occur. A significant portion of accidents occur at night ~30% (South African Easter 2015 stats showed 37% of accidents occurred between 1800 and 0600) An even higher proportion of fatalities occur at night…they are more severe. Overall most occur during the day ….~70% These figures are similar in motorized countries, also about 30% About 45% of the Fatalities in the US are at night. Source: “Road Transport Lighting for Developing Countries,” August 2002 Draft, CIE TC 4-37.

An effective and reliable communication system providing the safety and guidance information required for safe movement within the roadway system is a basic requirement of a Safe Roadway. Traffic Signs (& Road Markings) are the primary, and often sole, means of communication between Road System and Road User The main message here is that a developed road infrastructure is needed to have a good road safety record and high quality signing is a key part of that.

Road Safety Situation - Driver Information Needs Daytime Many landmarks available Driver task relatively easy Nighttime Few landmarks remain Task more difficult During daylight there many landmarks that assist to identify potential hazards At night these additional landmarks disappear.

Signs need to be as effective at night as they are during the day

Sometimes this requirement is not always met Daytime Night time

Legal Reference National Road Traffic Act 93 of 1996 (Sections 56 – 59) Chapter IX of NRTR 2000 Reg. 285 Purpose & Classification Reg. 286 Dimensions Reg. 286A Colours Reg. 287 Manner of Display Road Traffic Signs in South Africa are legislated by the National Road Traffic Act 93 of 1996 And Regulations contained in Chapter 9 of the National Road Traffic Regulations cover requirements of installed Road Traffic Signs

SABS National Standards SANS 1519-1:2006 Road Signs Part 1: Retro reflective sheeting material Class I / Class III / Class IVa & IVb Reflective / Colour/ Durability performance SANS 1519-2:2014 Road Signs Part 2: Performance requirements for road signs Coatings on finished sign (printing/vinyl/overlay etc.) Structural requirements Refers to SANS1519-1 for reflective requirements SANS 1555:2011 Roadworks Delineators SANS 1519-1 Material Reference (Class III minimum) Flexible signblade performance Locking mechanism to prevent blade separation from base There are South African National Standards that cover the quality aspects of road traffic signs in South Africa, namely.... CLICK......... SANS1519-1 covers requirements for reflective sheeting used on road signs. This includes testing the reflectivity, colour and durability performance of products. Reflective sheeting is classified ias either Class 1 & 2(low reflectivity performance), class 3 (medium reflectivity performance) or class 4 (high reflectivity performance) by measuring the product at a set of pre-determined lab geometries that simulate on road likely performance. Discussion is at SABS technical committee level to make this document a permit bearing standard to enable improved reference for contracts and tenders. There is also discussion taking place with the National Regulator for Compulsory Standards regarding compulsory status of the standard CLICK.......... SANS1519-2 covers the performance requirements of finished road signs. This standard is already a permit bearing specification, however, only two traffic sign manufacturers are currently certified as permit holders. This is due to the current cost of certification for many sign manufacturing companies, which is restrictive due to the high cost of the reflective sheeting testing - currently a requirement of this standard. When SANS 1519-1 is finalised as a permit bearing specification, the reflective sheeting testing cost would transfer from SANS 1519-2, which would make it more affordable for sign companies to apply for and maintain SANS certification status. Ultimately, we would support that the minimum qualification for Road Traffic Sign tenders and contracts includes SABS certification to ensure a sustainable standard of road traffic sign manufacturing is maintained CLICK.. SANS1555 covers road works delineators. The standard specifies a minimum of SANS 1519-1 Class 3 reflective sheeting on the sign face, defines the flexible performance of the blade and requires a locking mechanism to prevent separation of the blade from the base. This specification is referenced, via the revised SARTSM Volume 2, Chapter 13 document, to the Traffic Act and Regulations. It has also been proposed for inclusion, as a reference, in the COTO standard, currently under revision. .

General Policy and Sign Design Principals are contained in the Southern African Development Community (SADC) Road Traffic Signs Manual General policy and sign design principals are contained in the SADC Road Traffic Signs Manual. The content of Volume 1 provides description of the road traffic sign system and working detail on the use of each individual component of the system. Volume 4 provides complete dimensional details, together with accurate scalable drawings of all signs, markings and signals, including details of all letter types used on direction signs. The SADC manual was originally compiled during the mid 1990’s and was recently digitised in 2012. However, amendments to update the manual to include new and improved sheeting and manufacturing technology is still required. In addition, a project was recently completed to update South African Road Traffic Signs Manual (SARTSM) Volume 2, Chapter 13, Road Works Signing, to amend and digitise the document, and present the revised document to SADC for regional approval . .

Requirements of a Road Sign or Safety Device Fulfill a need Command attention Convey a clear, simple message Command the respect of road users Allow adequate time for the correct response from road users Contained in the SADC Manual is a description of required attributes of a traffic sign, namely to Fulfill a need Command Attention Convey a clear, simple message Command respect of road users and probably the most significant is to Allow adequate time for the correct response from the driver SADC Sign Manual 2012

SADC RTSM Guideline The manual also contains a table of the recommended SANS 1519-1 reflective sheeting class by sign series or type. I would like us to revisit this guideline and suitability of the table content in respect of today’s roadway conditions and technology availability at the conclusion of this presentation

So, how does Reflectivity work? Lets discuss the science behind reflectivity Reflectivity is “borrowed” light from another source. The borrowed light waves strike an object and “bounce” from it. The reflectance of the object – or how bright it shines – depends on the intensity of the light striking it and the materials from which it is made. .

3 Types of Reflection Reflection can be split into 3 types Diffuse reflection is the most common type of reflectivity and occurs when light strikes rough surfaces, such as a road surface, wall, clothing, etc. These surfaces cause the light beams to scatter in all directions. Only a small amount of the light is reflected back toward the source. Diffuse surfaces offer low Night time visibility to drivers. Mirror (specular) reflection occurs when light strikes surfaces that are smooth or glossy. The light reflects off the surfaces at an equal, but opposite angle to the source. This specular phenomenon may be experienced at night when diffused surfaces, such as roads, are covered with water. Distant lights and on-coming headlights glance off the wet pavement, instead of scattering in all directions, and create glare for the on-coming driver. Retroreflection occurs when surfaces return a portion of the directed light to its source. This is why retroreflective materials appear brightest to observers located near the light source – a driver and the vehicle headlights, for example.

Available Retro-Reflective Sheeting Technology for Road Traffic Signs The following are cross-section diagrams of the retro-reflective sheeting technologies available today.

Sign Sheeting Technology 1940 1970 Enclosed Lens Sheeting was the first durable reflective sheeting technology to be introduced in the late 1940’s. Incoming light is bent as it passes through the glass sphere and is reflected off a mirrored surface behind the bead. The light then passes back through the bead and returns the reflected light at a narrow entrance angle back to the source. Enclosed Lens Sheeting or Class 1 Engineer Grade has a durability warranty up to 7 years. Encapsulated Lens Sheeting was introduced in the 1970’s to provide improved retroreflection performance at wider entrance angles created by multi lane roads. Encapsulated Lens sheeting uses the same basic technology process as Enclosed Lens Sheeting, however each bead has a mirror coating at the back which provides light return or retro reflection from the wider entrance angle headlamp path experienced by vehicles on multi lane highway situations. Encapsulated Lens Sheeting or Class 3 High Intensity is has a 10 year durability term Prismatic Sheeting technology development and introduction in the mid 1980’s provided a significant improvement in light return efficiency. Truncated cube retro reflective performance provides 4 times the performance of light return efficiency when compared to enclosed lens bead technology and Full cube prismatic products provide double the light return efficiency of Truncated Cube products. Prismatic technology is extremely versatile and engineering development continues to date. Prismatic sheeting Class 4 carries a 12 year durability term for standard colours and 10 years for fluorescent colours. 1985-2015

Beads as Retro-reflectors Glass beads are used as retro-reflectors in Class 1 & 2 Enclosed Lens Engineer Grade, type products and Class 3 Encapsulated Lens High Intensity Grade (beaded) reflective sheeting As mentioned, glass bead technology use goes back to the 1940s Glass beads have limitations to the amount of light they can effectively retroreflect and only 28% of the surface area will return light just right, in order to benefit the driver The other 72% of the light falling on the glass bead is of no use to drivings as the light is scattered. Only 28% of spherical bead surface Bends light just right to cause retroreflection

Light entering the corner only reflects twice Truncated Cube Corners Have Limitations Light entering the corner only reflects twice Only 65% of the truncated cube surface is retroreflective The introduction of truncated cube corner optics in the mid 1980’s was a significant advancement compared to standard glass bead optics performance However, truncated cube corners have limitations also. 65% of the surface area of a truncated cube corner is “active” and returns light to the driver. Light entering the outer edges of truncated cube corners only reflects twice and, therefore, is not returned to the driver and is of no use.

Truncated cube corners (200x) Full Cube Optics Most Efficient Portion Truncated cube corners (200x) This photo is a magnification of a truncated cube corner reflective sheeting The two rectangles represent the active truncated cube corner area isolated for manufacturing a full cube corner reflective sheeting. This isolated section is then micro replicated to form the full cube reflective sheeting.

100% of full cube surface is retro-reflective Full Cube Optics Still uses mirror reflection There are no dead corners Full cube corner optics still use three bounce mirror reflection; however, 100% of the surface area will return light to the driver. This will enable a larger percentage of drivers to see the signs. 100% of full cube surface is retro-reflective

Available Technology - How Light Return Technology has Improved To summarise………. The first retro-reflective sheeting was introduced in the 1940’s One measure of the performance of a retro-reflector is its efficiency of returning light Each successive retro reflective sheeting generation has nearly doubled the retro reflective efficiency of the previous generation.

Retro-reflective Sheeting Efficiency Full Cube Truncated Prismatic Prismatic High Intensity Engineering Grade Grade Grade Grade A traffic sign’s retro reflective properties plays the deciding role in the nighttime performance of the road sign. As a percentage of the amount of incident light received: EG returns approximately 8% HI beaded returns 14% Truncated Prismatic Grade sheeting returns about 30%. So Truncated Prismatic Grade sheeting is about 4 times more efficient than EG and twice as efficient as HI. Full Cube Prismatic Grade sheeting returns about 58% of incident light. Twice as efficient as Truncated Cube 58% 32% 14% 8%

Reflectivity - Units of Measurement Intensity of a Light Source = Candela cd Illuminance: Light falling on a unit area lux Luminance: measured brightness of the reflected light from a surface Intensity / unit area cd / m2 The light source for nighttime driving is the vehicle headlamp. Light intensity from headlamps is measured in terms of candelas. It is a measure of how much light is emitted toward a certain direction from the light source. Light from headlamps falls on a surface, illuminating that surface. Light falling on a unit surface is measured in terms of lux. It is a measure of how much light is falling on a unit surface area. When light is reflected back to the driver from a surface, we talk about “luminance”. Luminance is measured in terms of candelas per square meter, and it is a measure of the brightness of the surface. How bright a sign appears to a driver is dependant on: 1) how much light is falling on the surface (lux), 2) the sheeting’s efficiency at returning light. The more efficient the sheeting, the brighter the sign will appear to a driver. Sign sheeting efficiency is measured in terms of candelas per lux per square meter. Government agencies control what drivers see by specifying certain sheetings for sign faces. Coefficient of Retroreflection: RA Luminance / Illuminance cd / lux / m2

Cone of Returned Light Retroreflector Reflected Light in Divergence Cone Light Source Direction To fully appreciate how retroreflective materials can help make our roads safer at night, it is helpful to understand these terms: cone of reflected light , observation angle and entrance angle Incident light on the retroreflective surface is retroreflected in a cone shape. A “perfect” retroreflector would send the light back to the headlight. That would be useless to the nighttime driver. Thus, some part of the light needs to be diverged from the incoming direction and return somewhere around the headlight where the driver is likely to be. Different sheeting materials distribute the retroreflected light differently. If a particular material redirects the otherwise scattered light to the driver eye, that material serves the driver better. The sign brightness observed by the driver is greatly affected by the location of the driver with respect to his/her headlights. The manner in which light is sent back to a driver is critical as to what that driver sees. Performance of retroreflective sheeting types can differ greatly.

Observation Angle The angle between the line formed by a headlight beam striking a sign surface and the line formed by the retro-reflected light beam at the driver’s eye This angle is usually small (e.g. 0,2 / 0,33 degrees) Observation angle is the angle between the line formed by a light beam striking a surface and the line formed by the retroreflected beam at the observer's eye.

Observation Angle Observation angle is a critical factor when determining how bright a sign appears As the observation angle increases the sign will appear less bright Observation angle can vary depending on the type of vehicle that is being driven.

Entrance Angle The angle between the line formed by a light beam striking the sign surface at some point and a line perpendicular to the sign surface at that same point. Entrance angle is the angle formed between a light beam striking a surface at some point and a line perpendicular to the surface at the same point.

Entrance Angle The position of the vehicle in relation to the sign will determine the Entrance Angle Larger angle (e.g. 5deg/30deg/60deg etc)

Entrance Angle The wider the Entrance Angle becomes will reduce the reflective performance (brightness) of the sign

Angularity Factors to Consider Where is the vehicle on the roadway What type of vehicle is it (e.g. truck or car) What is the position of the reflective sign in relation to the roadway Where is the reflective sign in relation to the vehicle

Windshield Transmission Factors that Determine Sign Brightness ROADWAY Critical Distances Glare Speed Background Complexity Surround Luminance Sign Size Roadway Alignment Legend Complexity Sign Position Sign Criticality Entrance Angle Sign Contrast Ratio Dirt on Sign VEHICLE Vehicle type Dimensions Headlamp types Headlamp output Windshield Transmission DRIVER Visual Acuity Age Perception Reaction Time Blood Alcohol Level There are many factors which determine the sign brightness intensity observed by the driver and must be considered when designing effective traffic signs.

Why Brighter Signs are Required .

Signing Considerations & Trends Aging Population Growing Truck Fleet VOA Headlamps We’ll look at some trends in transportation that affect sign performance requirements. First, we’ll look at the impact of the aging driver population.

Older Drivers Aging produces a natural decline in sensory, cognitive and motor (physical) functioning Studies show that required light need doubles every 13 years after the age of 20 Studies have determined that easier-to-see-and-read signs can help older drivers retain their freedom of mobility and reduce the likelihood of being involved in traffic accidents

Older Drivers * Night Lights...lighting the way (Answering Your Questions about Traffic Sign Retroreflectivity), U.S. Department of Transportation, Federal Highway Administration

Signing Considerations & Trends Aging Population Growing Truck Fleet VOA Headlamps We’ll look at some trends in transportation that affect sign performance requirements.

Larger Observation Angle for Trucks Camera 535mm above Headlight Camera 1270mm above Headlight The sign will have different luminance when viewed from different vehicles. Typically, the larger the vehicle, the dimmer the signs appear. SUVs and light trucks experience a similar effect but not quite as dramatic. The driver may be more like 30 inches above the headlights. .

Larger Observation Angle for Trucks Camera 535mm above Headlight Camera 1270mm above Headlight The sign will have different luminance when viewed from different vehicles. Typically, the larger the vehicle, the dimmer the signs appear. SUVs and light trucks experience a similar effect but not quite as dramatic. The driver may be more like 30 inches above the headlights. .

Signing Considerations & Trends Aging Population Growing Truck Fleet VOA Headlamps We’ll look at some trends in transportation that affect sign performance requirements.

Visually Optically Aimiable Headlights The differences in new headlight design can be viewed here. This a picture of a vehicle with VOA headlights.

Sign Design Principles The amount of light available to the traffic sign varies depending on the position of the sign and the vehicle. 17 % 14% 100 % 22 % This model describes the amount of incident light received in various sign locations. This will have an effect on the reflective performance of the sign when considering the percentage light return from the reflective sheeting utilised on the sign (E.G. Class 1 enclosed lens sheeting provides approx 8% light return, Class 3 prismatic sheeting will provide 32% and class 4 prismatic 58%)

Sign Viewing Distance- Scenario Basics Next Avenue Visual Acquisition Process Sign becomes visible as Sign becomes visible as a very small white object Sign becomes visible as Last Look a very small white object a very small white object Minimum Sign Reading Distance This slide depicts the basic process of sign viewing, understanding and thought process to completion of a driving manouver Source: TRB VIS 2005 “Percent Drivers Served” N.Johnson

Sign Viewing Distances – 2 Scenarios Carlton 50 Sandstone 10 Duluth 80 Next Avenue Sign Position (Overhead Urban) Letter Size 200mm Information Sign (1 line) 64 km/h (40 mph) 2.3 seconds reading time minimum Sign Position (Overhead Freeway) Letter Size 400mm Information Sign (3 lines) 120 km/h (75 mph) 3 seconds reading time Minimum Critical Distance Range: 150 - 50 meters Critical Distance Range: 71 - 30 meters This study considered two driver viewing scenario’s – Freeway and Urban type situations For Reference: Last Look : The distance range considers a last look distance when the sign is more than about 10 degree out of the drivers field of view. Reading Time: The reading time is based on the CIE report recommendation (that is 3 seconds for a 3 line sign, 2.3 seconds for one line) Vehicle Speed: The speed determines how far in advance of the last look the sign must be legible. Ref: TRB VIS 2005 “Percent Drivers Served” N.Johnson Additional Research: “Driver Eye Fixation and Reading Patterns while Using Highway Signs under Dynamic Nighttime Driving Conditions: Effects of Age, Sign Luminance and Environmental Demand” Schieber, Frank; Heimstra Human Factors Lab – University of South Dakota, TRB 2004-001951

Luminance Performance Comparison Class 4a&b (Full Cube Prismatic) Critical Distance Class 3 (Truncated Prismatic) This luminance graph provides a drivers view of the improvement of the visibility performance provided on the approach to a typical sign by the reflective sheeting technology developments discussed If I insert the critical distance segment, it becomes obvious that higher efficient sheeting provides improved performance for all drivers, including older drivers and those driving vehicles with wide observation angle (HGV / Buses etc.) Class 1(Enclosed Lens Bead) Class 1 Class 3 Class 4

Fluorescent Sheeting Technology Refers to the sheeting COLOUR performance Provides improved daytime colour and low light performance of signs (e.g. dusk, dawn, misty conditions) Fluorescent performance is included in SANS 1519-1

How Fluorescence Works Ordinary Colour Short wavelength light is absorbed by sign Short wavelength light is reemitted as longer wavelength light. Fluorescent Colour

Fluorescent Retro-reflective signs Fluorescent colour increases daytime sign visibility 40% earlier detection Eye tracking studies have shown additional 2,5 seconds decision and reaction time for drivers travelling at 80 km/h Fluorescent colors increase daytime visibility, providing drivers as much as 40% earlier detection than ordinary colors Results of eye-tracking studies of drivers have shown that drivers traveling at 80 km/h have an additional 2.5 seconds of decision and reaction time with fluorescent materials Fluorescent colors are different because they are, first, very intense They also possess a second property that allows them to take some light/energy that would normally be absorbed (not seen) and re-radiate it as longer, visible light waves Fluorescent colors are more efficient than ordinary colors at using the light/energy that reaches them. Source: Sintef, “Visual Performance of Fluorescent Retroreflective Traffic Control Devices,”

Cost Benefit Ratio Rank Improvement Desc. Benefit/Cost Ratio 1 Illumination 22.8 2 Upgrade Median Barrier 22.6 3 Traffic Signs 22.4 4 Relocated/Breakaway Utility Poles 17.7 5 Remove Obstacles 10.7 6 New Traffic Signals 8.5 7 Impact Attenuators 8.0 8 New Median Barrier 7.6 9 Upgrade Guardrail 7.5 10 Upgrade Traffic Signals 7.4 11 Upgrade Bridge Rail 6.9 12 Improve Sight Distance 6.1 13 Median for Traffic Separation 6.1 14 Groove Pavement for Skid 5.8 15 Improve Minor Structure 5.3 16 Turning Lanes and Channelization 4.5 17 New RR Crossing Gates 3.4 18 New RR Crossing Flashing Lights 3.1 19 Pavement Markings and Delineation 3.1 20 New RR Crossing Lights and Gates 2.9 FHWA research has shown that traffic signs are low cost safety measures, meaning the payback is very high. Source: Table IV-7 Highway safety improvements with the highest benefit-cost ratio

Cost Benefit Ratio Category # projects Av Cost £ Acc Red % % FYRR Roundabout 18 14769 49 134 Speed limits 6 1117 33 1035 Speed camera 28 18236 13 260 Traffic Calming 14 46093 57 216 Warning Signs 36 553 46 3491 Road Markings 63 2537 41 820 Traffic Signals 15 40717 67 157 This UK research also indicated a positive return ratio for providing traffic sign improvements Source: Royal Society for Prevention of Accidents (UK)

Components of a Road Traffic Sign Cost Effective Signs Components of a Road Traffic Sign Reflective Sheeting Sign Backing Sign Manufacture Labour costs Sign Post Sign Installation costs If we look at the components of a road traffic sign, they can be broken down as follows Reflective sheeting. Variable depending on class of sheeting and should be measured on reflective performance and durability Sign backing or substrate (mild steel / aluminium / etc) Labour cost to manufacture the sign face (lamination, screening, packaging, inventory, etc.) Sign post or poles Installation costs (transport, labour, hardware, etc) Effectively, the only variable cost for upgrading the reflective efficiency of a sign for a contract would be the reflective sheeting. As a portion of the total cost of the installed sign, this could be much less than anticipated, especially if the total cost is amortised over the life of the sign.

Key Points to Remember A developed roadway infrastructure is needed for road safety -- Effective Traffic Signs are a key part of this! High brightness signs (day and night) are used to improve roadway safety – They are cost effective! The distances at which higher brightness is provided is important – Critical Distance Truck Drivers and Older Drivers need signs which provide more brightness (especially at high observation angles) Daytime brightness of signs may be increased through the use of fluorescent reflective sheeting. Nighttime brightness of signs may be increased through the use of more efficient sheeting technology. In Summary, here are some key points to remember: A developed roadway infrastructure is needed for road safety -- Effective Traffic Signs are a key part of this! Higher brightness signs (day and night) are used to improve roadway safety – and they are cost effective! The distances at which higher brightness is provided is important – Critical Distance Truck Drivers and Older Drivers need signs which provide more brightness (especially at high observation angles) Daytime brightness may be increased through the use of fluorescent reflective sheetings. Nighttime brightness may be increased through the use of prismatic full-cube technology.

In 2015, should South Africa rely on technology from the 1940’s to Guide and Warn Motorists.....? So I pose the following question to you ....

What could possibly go wrong.......!! I mean...... WHAT COULD POSSIBLY GO WRONG !!

Recommendations Provide regular educational training programs to outline current requirements, available technology & recommendations for effective & compliant Road Traffic Signs / related products Review the current retro-reflective sheeting recommendations contained in Table 1.1 of SADC Sign Manual and amend to the Table to include latest sheeting technology Road Traffic Sign Manufacturing & Installation procedures need to be measured according to credible and implementable SABS standards SANS documents should be referenced and regulated in Road Traffic Sign contract & tender documents as the minimum qualification for tendering. Revise the SADC RTSM & South African Road Traffic Regulations to include the latest SABS standards references I would like to finish off with some recommendations.....

Proposed Sheeting Specification Permanent Signs Sheeting Class (SANS 1519-1) Type Series Background Border Text Symbol Arrow Regulatory Control Command Prohibition Reservation Comprehensive Selective Restriction De-restriction R1 – R6 R101 – R140 R201 – R242 R301 – R354 R401 – R403 R501 – R579 R600 3 1 SM 1 / SM Warning Advance Hazard W101 – W 363 W401 – W415 Guidance Location Route Marker/TB Direction Freeway Direction Tourism Local Direction Diagramatic Pedestrian Information GL GE GD (GM) GD (OH) GA / GB / GC GF GDL GS GP IN SM / 3 4 ! Temporary Signs Standard Temporary Signs Advance Warning / Hi Visibility background 4 (Fl Yellow) 3 / SM

Thank You Thanks for taking time to listen to my presentation today