Detectable Warnings: Testing and Performance Evaluation at Transit Systems - 

November 1994

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 NOTICE

 This document is disseminated under the sponsorship of

 the Department of Transportation in the interest of

 information exchange. The United States Government

 assumes no liability for its contents or use thereof.

 NOTICE

 The United States Government does not endorse products or

 manufacturers. Trade or manufacturers' names appear

 herein solely because they are considered essential to

 the objective of this report.

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 i

 PREFACE

Rail transit systems are required under ADA to place detectable

warnings along the edges of transit station platforms as a means of

alerting individuals who are blind or who have limited vision of

the drop-off hazard. The application of detectable warning

materials to existing transit station platform surfaces is a matter
of substantial concern to transit system personnel responsible for

selection and installation of such materials. This report, one of

a series on detectable warnings, sponsored by the Federal Transit

Administration, provides engineering information and guidance to

rail transit systems and other interested parties on the

performance of eight different materials that have been field

tested at three transit systems.

This report was prepared by Technology & Management Systems, Inc.,

of Burlington, Massachusetts. The authors, H. Norman Ketola and

David Chia, want to acknowledge the contributions that made this

report possible. The FTA's Office of Technical Assistance and

Safety sponsored the detectable warnings research with Lawrence L.

Schulman, Associate Administrator for Technical Assistance and

Safety; Vincent R. DeMarco, Director of the Office of Engineering

Evaluations; Ronald D. Kangas, Director, Rail Division; and Irving

Chambers, Project Manager, who provided direction and guidance. 

The project was conducted under a task order contract with the

Safety and Security Systems Division of the Volpe National

Transportation Systems Center. The authors wish to acknowledge the

extensive efforts and contributions of the following individuals at

the Volpe Center: William T. Hathaway, Project Supervisor; Patricia

H. Ryan, Project Manager/Contract Monitor; and Robert A. Rudich,

Senior Engineer.

The project would not have been possible without the full

cooperation of the eighteen detectable warning material

manufacturers who provided sample materials for laboratory testing

and the eight manufacturers who installed their materials for field

testing. These manufacturers are identified by name and contact

person within the body of the report. The authors also gratefully

acknowledge the full cooperation of the Massachusetts Bay

Transportation Authority (MBTA), the Greater Cleveland Regional

Transit Authority (GCRTA), and the Southeastern Pennsylvania

Transportation Authority (SEPTA) in providing test sites and

support services for the field testing of detectable warning

materials. In particular, we would like to acknowledge the

following individuals from the transit systems who provided

leadership on the field test activities and who also participated

in the meetings of the National Implementation Panel on Detectable

Warnings: William H. Bregoli, Chief Engineer, MBTA; John P.

Goodworth, Director of Passenger Facilities Programs, GCRTA; and

Carol H. Lavoritano, Assistant General Manager, Program Analysis,

SEPTA.

Robert W. Stout, Director, Office of Regional Operations and Ramon

H. Lopez, Senior Engineer, Office of Grants Management, both of the

FTA, also contributed their expertise to the National

Implementation Panel.
Finally, the authors would like to thank Tamara L. DeGray for her

contributions and effort in the preparation of this report.

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 TABLE OF CONTENTS

Section Page 

 1.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . 1-1

 1.1 Purpose and Scope . . . . . . . . . . . . . . . . 1-1

 1.2 ADA Regulatory Requirements . . . . . . . . . . . 1-2

 1.3 Technical Approach. . . . . . . . . . . . . . . . 1-4

 2. LABORATORY TESTING OF DETECTABLE WARNING MATERIALS . . 2-1

 2.1 Detectable Warning Manufacturer Participation . . 2-1

 2.2 Laboratory Testing Protocol and Results . . . . . 2-3

 2.3 Selection of Materials for Field Testing. . . . . 2-5

 3. FIELD TEST INSTALLATIONS AND PERFORMANCE RESULTS . . . 3-1

 3.1 Field Test Installations. . . . . . . . . . . . . 3-1

 3.1.1 Selection of Installation Sites . . . . . . 3-1

 3.1.2 Preparation for Installation Activities . . 3-2

 3.1.3 Installation. . . . . . . . . . . . . . . . 3-3

 3.2 Field Test Results . . . . . . . . . . . . . . . . . . 3-9

 3.2.1 Field Test Results - Condition of the

 Material and Installation After 

 Exposure. . . . . . . . . . . . . . . .3-11

 3.2.2 Summary of Field Test Results - Condition

 of Material and Installation. . . . . .3-24

 3.2.3 Field Test Results - Measurement of Wear

 Resistance. . . . . . . . . . . . . . .3-34

 v

 TABLE OF CONTENTS (Continued)

Section Page 

 4. COMPARATIVE PERFORMANCE OF DETECTABLE WARNING SYSTEMS. 4-1
 4.1 Installation and Maintenance of Detectable Warning

 Systems . . . . . . . . . . . . . . . . . . . . . 4-1

 4.1.1 Observations and General Conclusions

 Regarding Installation. . . . . . . . . 4-1

 4.1.2 Maintenance of Detectable Warning 

 Systems . . . . . . . . . . . . . . . . 4-3

 4.2 Performance Assessment. . . . . . . . . . . . . . 4-4

 4.2.1 Considerations in Interpreting 

 Rankings. . . . . . . . . . . . . . . . 4-4

 4.2.2 Performance Rankings. . . . . . . . . . 4-6

 5. SUMMARY OF NATIONAL IMPLEMENTATION PANEL ACTIVITIES. . 5-1

 5.1 Panel Composition . . . . . . . . . . . . . . . . 5-1

 5.2 Panel Activities. . . . . . . . . . . . . . . . . 5-4

 5.3 Summary of Technical Information from the Panel . 5-5

 5.3.1 Experiences with Detectable Warning

 Procurement and Installation. . . . . . 5-5

 5.3.2 Tips for Implementing Detectable Warning

 Requirements. . . . . . . . . . . . . . 5-7

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . R-1

APPENDIX A. INFORMATION ON MATERIALS INCLUDED IN LABORATORY

 TESTS

APPENDIX B. INSTALLATION DATA COLLECTION FORM

APPENDIX C. FIELD TEST DATA AND OBSERVATION FORM

APPENDIX D. DOME HEIGHT MEASUREMENTS AND COMPUTATION OF WEAR

 vi

 LIST OF FIGURES

 Figure Page 

 1-1 Detectable Warning Dimensions. . . . . . . . . . . . . 1-5

 3-1 Specification Sheet for Orient Heights Station . . . . 3-8
 3-2 Rehau: Access Tactile Tile Installation at MBTA South

 Station Illustrating Missing Tile. . . . . . . . . . .3-14

 3-3 Transpo Industries: Step-Safe Installation at MBTA

 Orient Heights Station Illustrating Cracked Tile . . .3-15

 3-4 ADA Consultants: Alert Mat Installation at GCRTA

 Brookpark Illustrating Change from Original Color. . .3-18

 3-5 Transpo, Industries: Step-Safe Installation at GCRTA

 Triskett Street Station Illustrating Chipped Domes . .3-19

 3-6 Rehau: Access Tactile Tile Installation at SEPTA

 8th Street Station Illustrating Lifting Tiles

 and Loose Caulking . . . . . . . . . . . . . . . . . .3-22

 3-7 Engineered Plastics: Armor-Tile Installation at SEPTA

 Bethayres Station Illustrating Small Accumulation of

 Dirt and Sand. . . . . . . . . . . . . . . . . . . . .3-23

 3-8 Arrangement of Detectable Warning Materials at MBTA

 South Station Test Site. . . . . . . . . . . . . . . .3-35

 3-9 Projected Annual Wear Rate of Detectable Warning

 Materials at Platform Edge for Low Passenger Volume

 Station at GCRTA (Brookpark) . . . . . . . . . . . . .3-38

 3-10 Projected Annual Wear Rate of Detectable Warning

 Materials at Platform Edge for High Passenger Volume

 Station at MBTA (South Station). . . . . . . . . . . .3-39

 vii

 LIST OF TABLES

 Table Page 

 2-1 Manufacturers Participating in Laboratory

 Testing Program . . . . . . . . . . . . . . . . . 2-2

 2-2 Detectable Warning Materials Selected for

 Field Test. . . . . . . . . . . . . . . . . . . . 2-6

 3-1 Field Test Installation Sites. . . . . . . . . . . . . 3-4

 3-2 Station Environment. . . . . . . . . . . . . . . . . . 3-5

 3-3 Installation Site Issues . . . . . . . . . . . . . . . 3-7
 3-4 Completed Test Installations . . . . . . . . . . . . .3-10

 3-5 MBTA Test Installations. . . . . . . . . . . . . . . .3-13

 3-6 GCRTA Test Installations . . . . . . . . . . . . . . .3-17

 3-7 SEPTA Test Installations . . . . . . . . . . . . . . .3-21

 3-8 Performance of Installed Materials:

 ADA Consultants "Alert Mat . . . . . . . . . . .3-25

 3-9 Performance of Installed Materials:

 Carsonite International "Pathfinder . . . . . . .3-26

 3-10 Performance of Installed Materials:

 Crossville Ceramics "Tac-Tile . . . . . . . . . .3-27

 3-11 Performance of Installed Materials:

 Engineered Plastics "Armor-Tile . . . . . . . . .3-28

 3-12 Performance of Installed Materials:

 Hastings Pavement "ADA Pavers . . . . . . . . . .3-29

 3-13 Performance of Installed Materials:

 Rehau "Access Tactile Tile. . . . . . . . . . . .3-30

 3-14 Performance of Installed Materials:

 Summitville Tile "Tactile-Tread . . . . . . . . .3-31

 3-15 Performance of Installed Materials:

 Transpo Industries "Step-Safe . . . . . . . . . .3-32

 viii

 LIST OF TABLES (Continued)

 Table Page 

 4-1 Ranking of Materials by Resistance to Wear . . . . . . 4-7

 4-2 Ranking of Materials by Maintenance of

 Bond with Surface . . . . . . . . . . . . . . . . 4-8

 4-3 Ranking of Materials by Resistance to

 Chipping and Cracking. . . . . . . . . . . . . . 4-9

 4-4 Ranking of Materials by Maintenance of Color . . . . .4-10
 4-5 Summary of Performance Rankings. . . . . . . . . . . .4-11

 5-1 National Implementation Panel for Detectable

 Warnings Panel Member List. . . . . . . . . . . . 5-2

 5-2 National Implementation Panel for Detectable

 Warnings Panel Observer List. . . . . . . . . . . 5-3

 ix/x

 1. INTRODUCTION

The Americans with Disabilities Act (ADA) of 1990 requires that all

transportation facilities and vehicles be accessible to persons

with disabilities. The U.S. Department of Transportation (U.S.

DOT) has issued regulations covering transportation facility

accessibility, which include a requirement that detectable warnings

must be installed along the edges of transit station platforms to

alert individuals who are blind or who have limited vision of the

drop-off hazard. This requirement is applicable to all new transit

stations and to certain existing stations that have been designated

as "key stations."

A detectable warning is defined as a standardized surface feature

built in or applied to walking surfaces or other elements to warn

individuals with visual impairments of hazards along their path of

travel. Persons with little or no usable vision rely on tactile,

sound, and resilience contrasts to detect hazards. Persons with

some vision rely on visual contrasts to detect hazards. For the

transit station application, the detectable warning is a 24-inch

wide strip running the full length of each platform edge. The

standardized surface incorporates closely-spaced small projections

or bumps, known as truncated domes.

1.1 PURPOSE AND SCOPE

The transit industry has expressed its concerns to U.S. DOT

regarding potential problems with detectable warning materials,

particularly, when they are applied to existing transit platform

surfaces. These concerns include the potential loss of adhesion

between the material and the platform surface, the basic durability

and wear characteristics of the materials, and the maintainability

(i.e., cleaning and snow and ice removal) of the installation.
This report is intended to provide information and guidance to rail

transit systems based upon the results of a comprehensive

performance test and evaluation of detectable warning materials. 

The scope of the testing and evaluation program included:

 - Laboratory testing of eighteen detectable warning

 materials.

 - In-service performance evaluation of eight detectable

 warning material installations at six transit stations

 located at three transit systems (MBTA in Boston, GCRTA

 in Cleveland, and SEPTA in Philadelphia).

The focus of the testing and evaluation program was on engineering

performance characteristics of the materials and the durability of

the field installations on transit station platforms.

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The data and results from both the laboratory tests and

approximately seven months of weather exposure and foot traffic are

presented in this report, including material performance in:

 - Adhesion/bonding to platform surface.

 - Chipping or cracking.

 - Changes in appearance (color).

 - Slip resistance.

 - Wear resistance.

The report also includes a summary of the findings of a National

Implementation Panel for Detectable Warnings. The Panel was formed

to provide guidance on the engineering testing and evaluation

efforts and to provide a means of gathering and disseminating

information about the process of selecting, installing, and

maintaining detectable warning materials. Panel members were drawn

from rail transit systems, individuals with disabilities who use

rail transit, and disability advocates.

The FTA has also sponsored a number of human factors research

projects conducted by Boston College related to detectable

warnings. The results of these projects, which are presented in

References I and 2, include:

 - Under-foot detectability of thirteen different warning

 surfaces in a simulated transit platform setting.
 - Negotiability (ease/difficulty of maneuvering) on nine

 different detectable warning surfaces placed on a ramp

 with a slope of 1: 12.

 - Detection of visual contrast by persons having very low

 vision.

1.2 ADA REGULATORY REQUIREMENTS

This subsection is intended to provide some background information

on the evaluation of the regulatory requirements for detectable

warnings in transit systems. There have been a number of changes

in the regulatory requirements for detectable warnings since the

Americans with Disabilities Act (ADA) was signed into law on July

26, 1990.

The ADA requires that the Architectural and Transportation Barriers

Compliance Board (Access Board) issue guidelines to ensure that

buildings, facilities, and vehicles covered by the law are

accessible to individuals with disabilities, in terms of

architecture and design,

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transportation, and communication. Regulations issued by the U.S.

Department of Transportation (U.S. DOT) must be consistent with the

Access Board's guidelines. The Access Board issued the Americans

with Disabilities Act Accessibility Guidelines (ADAAG) for

buildings and facilities on July 26, 1991; and amended it on

September 6, 1991, to include additional requirements for

transportation facilities. U.S. DOT has adopted ADAAG as the

accessibility standard for new construction and alteration of

transportation facilities by public entities covered by Title II of

the ADA and for transportation vehicles covered by Titles II and

III.

On November 17, 1992, the U.S. DOT published a Notice of Proposed

Rulemaking (NPRM) in the Federal Register to amend its rules,

implementing the ADA. The NPRM stressed U.S. DOT's concerns about

how best to retrofit existing station platforms with detectable

warning materials. One modification proposed extending the

compliance date by eighteen months (from July 26, 1993 to January

26, 1995) for the requirement to install detectable warnings in

existing key stations. DOT reasoned, in the NPRM, that rail

operators may need additional time to resolve issues of adhesion,

durability, and maintainability of detectable warning materials in
the context of key station modifications. The NPRM also noted that

the Federal Transit Administration (FTA) would pursue additional

research and evaluation concerning the durability and detectability

of tactile warnings during the extension period that may help rail

operators in their efforts to solve the retrofit application

problem. This report represents one element of the FTA's efforts

to provide additional information.

On November 30, 1993, U.S. DOT issued a Final Rule, amending the

completion date for the installation of detectable warnings in key

stations to July 26, 1994. The U.S. DOT response in the rule

stated that the twelve-month extension, compared to the eighteenmonth extension proposed in the NPRM, would give transit properties

sufficient time to work out installation and related problems

without unduly delaying the addition of this important safety feature.

In addition to the FTA research efforts, the Access Board is

conducting a research project on the need for and effectiveness of

detectable warnings on curb ramps and on walkways that adjoin a

vehicle area where there are no curbs. The research project

includes postconstruction evaluations at thirty sites involving

curb ramps and hazardous vehicle areas which have detectable

warnings as required by ADAAG, and at thirty other sites that were

constructed without detectable warnings.

The Access Board's detectable warning research project also

contains an optional Phase II which includes testing the usability,

detectability, and wearability of detectable warnings in the curb

ramp application; developing draft recommendations for technical

and scoping changes for detectable warnings in the ADAAG; and

developing a composite technical report and technical article.

On April 12, 1994, the Access Board published a joint final rule

with the Department of Justice and U.S. DOT to suspend

temporarily - until July 26, 1996 - requirements for detectable

warnings at curb ramps, hazardous vehicular areas, and reflecting

pools. This

 1-3

action does not affect the ADAAG requirement for detectable

warnings at transit platforms, which remains in effect.

The dimensions of the standardized detectable warning surface have

been specified by the Access Board in the ADAAG (at 4.29.2). These

consist of a standardized surface that incorporates small truncated

domes at closely spaced intervals (see Figure 1-1). The

requirements for detectable warnings in transportation facilities

were published in Section 10 of the ADAAG. The Access Board
required platform edges bordering a drop-off and not protected by

platform screens or guard rails to have a detectable warning 24-

inches wide running the full length of the platform drop-off in new

construction, "key stations" (i.e., existing facilities meeting

U.S. DOT criteria), and intercity rail stations.

The Access Board issued "Bulletin #1: Detectable Warnings" in May,

1992, to provide technical guidance to manufacturers and purchasers

of detectable warning materials. A revised version of Bulletin #1

was issued in April, 1994 (Reference 3). The dimensions shown in

Figure 1-1 are based on diagrams presented in Bulletin #1.

1.3 TECHNICAL APPROACH

The comments submitted by the industry in response to the

rulemaking process indicated that operators of rail transit

systems were seeking technical information to answer the following

questions:

 - What problems can be expected if a detectable warning

 material is installed on top of platforms made of

 concrete, asphalt, or wood?

 - Which materials are most slip-resistant under all

 potential weather and wetness conditions?

 - Which material installations are the most durable in

 terms of retaining their original characteristics and

 physical configuration (particularly no lift-off or

 separation of edges) after extensive use and weather

 exposure?

 - Which materials can be mechanically fastened to provide

 additional protection against lift-off or separation?

 - Which materials are most resistant to the effects of

 cleaning and maintenance, particularly, snow removal?

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 1-5
It was anticipated that the answers to these general technical

questions would assist transit systems in selecting materials which

best fit their system needs. Furthermore, it was expected that no

single material/method of installation would prove to be superior

in all respects for all situations. For this reason, it was

decided that engineering and field test results would be presented

in the form of a comparative evaluation of the performance of all

detectable warning materials that were selected for testing and

evaluation. Individual transit systems could then use the

information from the program, along with their own test results on

detectable warning materials, to decide the most suitable for their

needs.

There were a number of issues and considerations that had to be

factored into the technical approach for the testing and evaluation

program. These issues and considerations included: the wide

variety of products, indoor and outdoor station requirements, and

retrofitting platforms.

Number of Manufacturers, Product Options, and Updates.

There are a large number of detectable warning manufacturers, with

some offering two different types of materials such as coated metal

and polymer composites. In addition, many manufacturers follow a

product improvement cycle in which they are regularly making

changes in the chemical formulation of the base products, or in the

coatings, adhesives, or the mechanical design of the product.

Indoor vs. Outdoor Stations.

The requirements for detectable warning material installation at an

indoor station are considerably different than those of an outdoor

station. For example, the ADAAG requires that interior

applications provide a contrast in resilience or in sound when

sensed by a cane compared to the adjoining walking surface. With

interior stations there are also more concerns with regard to fire

resistance of the material and the presence of any volatile organic

compounds (VOCs) during the installation process. Outdoor

installations have to be more resistant to weather exposure (snow,

ice, and sun) and the effects of maintenance (snowplowing and

deicing chemicals).

Transit Station Platform Construction.

The retrofit of detectable warning materials onto existing

platforms is affected by the underlying material surface. Many

transit systems have a variety of station construction designs,

where the detectable warning material must be placed onto a base

surface such as concrete, asphalt, ceramic tile, or wood.

The effect of the factors noted above required that the test

program be structured in a manner that narrowed the number of
combinations of materials/installations/stations to be field tested

in an operating transit environment. To ensure that outcome, the

following approach was used.

 - Each manufacturer participating in the demonstration

 program was allowed to submit one material for testing:

 the one it believed to be best for the outdoor

 application. An outdoor installation provides a more

 rigorous environment to test the performance of the

 materials with regard to adhesion, durability, and wear.

 1-6

 - The detectable warning materials submitted by

 participating manufacturers were first subjected to

 laboratory testing by an independent laboratory. The

 laboratory tests were used to measure mechanical

 properties and durability characteristics using

 standardized (American Society for Testing and

 Materials - ASTM) test protocols.

 - The materials that exhibited better performance in the

 laboratory tests were selected as candidates for

 installation at transit stations for the field test

 portion of the demonstration program. No changes in the

 type or composition/installation characteristics by the

 manufacturers were allowed between the laboratory tests

 and the field test.

 - Field tests were conducted at both indoor stations and

 outdoor stations to demonstrate a full range of

 environmental and passenger use impact on the selected

 materials. All installations were made on existing

 concrete platforms or passageways, with the exception of

 one interior installation on an existing paver tile

 surface.

The technical approach to data collection during the installation

and field testing was designed to provide information on of the

following issues and performance characteristics:

 - Retrofit installation. Requirements of time, level of

 effort, special tools/equipment, and assessment of skills

 to install detectable warning materials at an existing

 transit platform edge.

 - Installation integrity over time. An evaluation of any
 lift-off or separation of the materials from the

 substrate, fractured or chipped domes, cracked or broken

 tiles, loosened or missing mechanical fasteners, buckling

 or rolling of surface, or evidence or water penetration

 under the surface.

 - Durability. Wear measurements determined by the change

 in average dome height after a uniform time period and

 changes in the appearance (color) of the surface after

 exposure.

 - Weather-related performance. Changes in the material or

 installation attributable to weather conditions such as

 freeze-thaw, exposure to sun, or use of salt or other

 deicing agents.

 - Maintenance-related performance. Effect of cleaning

 agents/techniques on surface color or staining, evidence

 of gum remnants or cigarette bums, and effect of snow and

 ice removal.

 1-7/8

 2. LABORATORY TESTING OF DETECTABLE WARNING MATERIALS

This section provides a description of the process used to identify

detectable warning manufacturers, the laboratory testing that was

conducted on sample materials submitted by participating

manufacturers, an examination of test results, and the selection of

materials for field test installation at transit station platforms.

2.1 DETECTABLE WARNING MANUFACTURER PARTICIPATION

The following procedure was used to identify detectable warning

manufacturers and solicit their participation in the program.

 - Letters were sent to twenty detectable warning

 manufacturers identified by the Access Board in Bulletin

 #1 (Reference 3) and those additional manufacturers that

 responded to a notice placed in the Commerce Business

 Daily (April 5, 1993) by the Volpe Center. Out of the

 twenty manufacturers, one did not respond, and another

 responded but declined to participate.

 - Manufacturers that responded to the initial letter were

 requested to send twenty sample pieces of their product
 to an independent laboratory for testing. Eight of the

 sample pieces were to be bonded to a concrete substrate.

 - A total of fourteen manufacturers responded to the

 request and submitted samples. The manufacturers are

 identified in Table 2-1. In addition, Table 2-1 contains

 the names of an additional four manufacturers that had

 indicated an interest in participating in the FTA

 program, but whose materials were already being tested by

 the same independent laboratory under a program sponsored

 by the New York MTA's Metro-North Commuter Railroad

 (MNCR). Since the same tests were being conducted, the

 test results for these four additional materials were

 also considered (under a cooperative agreement with the

 MNCR) as potential candidates for the FTA field test

 program.

Appendix A provides detailed information on each of the eighteen

detectable warning materials identified in Table 2-1 including the

name and telephone number of the manufacturer, the type of material

and dimensions, and typical fastening methods.

 2-1

 Table 2-1

 Manufacturers Participating in Laboratory Testing Program

 MANUFACTURER TRADE NAME MATERIAL DESCRIPTION

A. Materials Tested Under FTA Program

ADA Consultants Alert Mat Blended rubber compounds

Advantage Metal Systems Detectable Warning Polymer coated

 Systems steel or aluminum

Bridgco ADA Path Polymer concrete

COTE-L Enterprises Safti-Trax Polyurethane domes with

 "Durabak" polyurethane

Crossville Ceramics Tac-file Unglazed ceramic tile

Dal-Tile Corp. Detectable Warning Unglazed porcelain

 Tile tile

Hastings Pavement Co. ADA Pavers Pre-cast clay or shale

 bricks
Inco Chemical Supply Co. T.actile Warning Polymer concrete

 System

NBS/Aware & Concerned Detectable Warning Rubber mat

Services Mat

Rehau, Inc. Access Tactile Tile Thermoplastic polyurethane

Steps Plus, Inc. Detectable Warning Pre-cast concrete

 Units

Summitville Tile Tactile-Tread Glazed porcelain tile

Transpo Industries Step-Safe Polymer concrete

Whitacre-Greer Paver Slate bricks

B. Materials Tested Under the MNCR Program

Carsonite International Pathfinder Fiber reinforced polymer

 composite

Engineered Plastics Armor-Tile Vitrified polymer composite

High Quality Tactile Tac Strip Polymer composite

Systems

Strongwall Systems Strongwarn Two-component polymer

 concrete

 2-2

2.2 LABORATORY TESTING PROTOCOL AND RESULTS

A brief summary of the laboratory testing program procedures and

results are presented here. (For the complete description see

Reference 4.) The following laboratory test protocol was adapted

based on consultation with the testing laboratory. Whenever

possible, the laboratory test procedure was selected from the

applicable American Society for Testing and Materials (ASTM)

standard test methods.
 LABORATORY TEST PROTOCOL FOR DETECTABLE WARNING MATERIALS

 1. Water Soaking Screening (Non-ASTM)

 (initial soaking of samples in a water bath for 55

 hours)

 2. Adhesion/Bond Strength - ASTM C 482 (Dry and Wet)

 (applicable to bonded material samples)

 3. High Pressure Hot Water Resistance (Non-ASTM)

 (representative of heavy duty surface cleaning

 procedure)

 4. Wear Resistance - ASTM D 658 (Sandblasting)

 5. Slip Resistance - ASTM C 1028 (Dry and Wet)

 (to include recessed areas between truncated domes

 when applicable)

 6. Impact Resistance - ASTM D 3029 (Cold and Hot)

The general procedure was to conduct each test on all of the

materials following the protocol shown above. If a material or

bonded sample performed very poorly in the water soaking screening

or adhesion/bond strength tests, it was excluded from the balance

of the test protocol. The results of the laboratory testing are

summarized below.

 - The water soaking screening tests (non-ASTM) were

 performed on all materials submitted. After soaking in

 water for fifty-five hours, materials that were bonded to

 a substrate were put through the wet strength portion of

 the adhesion/bond strength tests (ASTM). The bond

 strength test is a wedge test whereby a wedge or "knife

 edge" is forced in between the material and the substrate

 and a measurement is made of the force required to cause

 a failure in the bond. Four of the fourteen materials

 tested under the FTA program (and one under the MNCR

 Program) completely failed the wet adhesion/bond strength

 test, i.e., the detectable warning material separated

 from the substrate with zero force applied (peeled off

 easily by hand). These four materials were screened out

 from further testing. Three additional materials were

 found to have poor adhesion/bond strength; however, other

 laboratory tests were conducted to confirm the testing

 laboratory's assessment of material quality.

 2-3
 Four materials that were bonded by adhesive to a

 substrate provided good test results with wet

 adhesion/bond strength ranging from 200 to 1,250 pounds

 of force. An adhesion/bond strength test was not

 conducted on four other materials which were mechanically

 bonded and on two others submitted as unbonded samples.

 - The high pressure hot water tests demonstrated very

 little variation in product performance for the materials

 tested. These tests essentially confirmed the earlier

 results that were found in the water soaking screening

 and adhesion/bond resistance tests.

 - The wear resistance tests showed a wide variety in

 performance of the various detectable warning materials. 

 The wear created by the sandblast (as measured by the

 depth of the hole created) ranged from zero to nearly one

 inch after thirty seconds of blasting. Most materials

 were in the 0.1 inch to 0.2 inch depth range after thirty

 seconds.

 - The slip resistance tests showed that all of the

 materials were slip resistant and none of them had a

 coefficient of friction (COF) less than 0.6. This is the

 minimum value recommended by the Access Board. The range

 of COF values in dry conditions ranged from a low of 0.81

 to a high of 1.14. In wet conditions, the range was

 0.66 to 1.03.

 - The impact resistance tests were conducted under room

 temperature, hot, and cold conditions. These tests also

 demonstrated a wide range of material performance. In

 general, rubber-based and polymer composite materials

 performed quite well, and the more rigid products

 (cementitious and ceramic tile), as one might expect,

 performed poorly. Eight of the products tested were

 found to be reasonably impact-resistant under all

 temperature conditions.

It should be noted that the materials tested under the MNCR Program

were subjected to a more extensive set of laboratory tests. These

additional tests included the Flame Spread Index Test (ASTM E 84),

which measures flammability and smoke emission parameters. All of

the polymer composite materials tested under the MNCR Program

(Carsonite International's Pathfinder, Engineered Plastic's Armor-
Tile, and High Quality Tactile Systems' Tac Strip) were subjected

to this test. The detailed results from these fire tests, and all

other tests conducted, are presented in Reference 5. With regard to

the ASTM E 84 test, all of the materials tested exhibited fire

resistance characteristics which were quite favorable.

 2-4

2.3 SELECTION OF MATERIALS FOR FIELD TESTING

A total of ten detectable warning material products were selected

for field testing, as shown in Table 2-2. These ten materials were

selected on the basis of their relative performance in each of the

laboratory tests. All materials that were tested in the slip

resistance and high pressure hot water tests effectively passed

each test, i.e., the COF was above the minimum value and the

materials were not affected by the water. Therefore, the materials

selection was based on the results from the water soaking

screening, adhesion/bond strength, wear resistance, and impact

resistance.

The ten selected manufacturers were invited to participate in the

field testing program. The invitation included a request that the

materials be installed at each of the three transit systems

(Boston, Cleveland, and Philadelphia) that had been selected as

demonstration test sites. Two of the ten manufacturers, as

indicated in Table 2-2, declined the request for field testing of

their products.

 2-5

 Table 2-2

 Detectable Warning Materials Selected for Field Test

 MANUFACTURER TRADE NAME

ADA Consultants Alert Mat

Bridgco* ADA Path

Carsonite International Pathfinder

Crossville Ceramics Tac-Tile

Engineered Plastics Armor-Tile
Hastings Pavement ADA Pavers

High Quality Tactile Systems* Tac Strip

Rehau Access Tactile Tile

Summitville Tile Tactile-Tread

Transpo, Industries Step-Safe

* These two manufacturers declined the invitation to participate in

the field test portion of the program.

 2-6

 3. FIELD TEST INSTALLATIONS AND PERFORMANCE RESULTS

This section of the report describes the field test portion of the

program including: a discussion of the purpose of the field testing

and the types of information that were collected; the selection of

the test sites; the activities conducted to coordinate and oversee

the installation of the detectable warning material at the test

sites; and performance results from the test installations,

presented for each test site and for each installed material.

3.1 FIELD TEST INSTALLATIONS

The primary goal of the field testing was to document the

performance of the selected detectable warning materials when

subjected to the rigors of revenue transit service. A secondary

goal of the field testing was to observe and document the

installation procedures of these materials in a retrofit

application.

The initial activities of the field testing involved the

installation of the detectable warning materials at the transit

system test sites. At each system there was an indoor site and an

outdoor site. Each installation was monitored and information

recorded through written notes, photographs, and videotapes. Data

was collected on many subjects: the skill, effort, and tools -

required for installation; the versatility of the materials under

various conditions; and the appropriateness of the materials for

retrofit.

The three indoor installation sites were not located along transit
platform edges; rather, the sites were located within their

respective stations in corridors that had high pedestrian traffic. 

The intent of these placements was to expose the materials

installed indoors to "accelerated" wear in comparison to the wear

that they would undergo if installed along a platform edge. This

helped to compensate for the compressed time frame of the field

testing.

Of the three outdoor installation sites, two were along rapid rail

platform edges and one was adjacent to a commuter rail platform

edge. The materials installed at these sites were also exposed to

pedestrian traffic. The primary purpose for the outdoor

installations, however, was to expose the materials to the effects

of weather (particularly winter conditions) and the winter

maintenance practices of the transit systems, e.g., snow and ice

removal.

3.1.1 Selection of Installation Sites

Selection of the transit systems was based on the following

criteria:

 - Rail stations, both indoor and outdoor, where test

 materials could be installed, were available to the

 transit systems.

 3-1

 - The availability of the rail stations fit within the time

 frame of the project.

 - The transit system was located in an area with snowy and

 icy winters.

 - The transit system was able to provide some technical and

 administrative support in arranging and monitoring the

 installations.

 - The transit system allowed cutting and removal of

 concrete substrate from platform edges and interior

 corridors to accommodate the placement of detectable

 warning materials.

After reviewing the criteria with several transit systems, the MBTA

(Boston), GCRTA (Cleveland), and SEPTA (Philadelphia) were

selected. These transit systems met the criteria and also

expressed their interest in acting as hosts for the field tests and
in using the findings of the demonstration and evaluation program

to help them choose detectable warning materials for their rail

stations.

3.1.2 Preparation for Installation Activities

Once the MBTA, GCRTA, and SEPTA agreed to host the field tests, it

was necessary to work closely with staff from each of the systems

to select the stations where the installations would take place and

to set up procedures for scheduling individual installations.

The installation sites at the indoor stations had to meet these

criteria:

 - High pedestrian traffic.

 - Surface that could be cut to a depth of, at least, three

 inches.(1)

 - Once installed, the materials would not disrupt passenger

 flow or confuse individuals with vision impairments.

The three outdoor installation sites had to meet these criteria:

 - Direct exposure to precipitation.

 - Surface that could be cut to a depth of, at least, two

 inches.(2)

 - Once installed, the materials would not pose a safety

 hazard to passengers or confuse individuals with vision

 impairments.

___________________________

(1) The depth of surface cut at the indoor locations was based on

the need to accommodate a thick material (approximately 2 inches).

(2) The depth of cut at the outdoor locations was based on the

need to avoid cutting of platform edge structural reinforcements.

 3-2

In addition, the host transit systems had their own considerations

in the selection of the installation sites. For example, all three

systems chose outdoor sites at stations that were scheduled to have

major renovations within the next few years. Table 3-1 lists the

six installation sites for the field tests.

Table 3-2 provides information about each station's passenger

traffic, exposure to the environment, and transit system
maintenance.

The operations, facilities, and engineering divisions of the host

systems were involved to make sure that electric power and water

needed by the installers would be available at the installation

sites. It was also necessary to determine the times and days when

installation could take place and provide any special arrangements

that were necessary for an installation (e.g., flaggers; for work

along a track). Table 3-3 lists installation size, the times and

days available for installation, and special conditions for

installation of the detectable warning materials.

Coordination of the test installations with the manufacturers began

immediately after their products were selected for the field tests. 

The dates for each installation were arranged to meet the schedules

of both the manufacturer and the transit system. In addition, some

of the installations involved a fourth party: manufacturers that

did not have in-house staff to install their material had to hire a

local contractor to perform the work.

In advance of the installations, manufacturers were provided

information, including a station specification page, on each of the

installation sites. Figure 3-1 presents a sample specification

page. Each manufacturer that installed its material at the MBTA's

Orient Heights station received this specification page.

3.1.3 Installation

Each test installation of the manufacturers' detectable warning

materials was monitored by the project staff. Monitoring

responsibilities included the recording of information and

observations about the installation on a data collection form. The

information collected included:

 - Weather conditions (for outside installation).

 - Installation size and location.

 - Installation crew size and tools used.

 - Installation steps.

Appendix B presents the data collection form used at installations. 

In addition, photographs and videos were taken of each

installation.

 3-3

 Table 3-1

 Field Test Installation Sites
 SYSTEM STATION (LINE) LOCATED WITHIN STATION

Outdoor

 MBTA Orient Heights Outbound Platform Edge

 (Rapid Transit - Blue Line)

 GCRTA Triskett Street Outbound and Inbound

 (Rapid Transit - Red Line) Platform Edges

 SEPTA Bethayres At Top of Steps Between

 (R3 Commuter Rail) Platforms and Station

Indoor

 MBTA South Station Pedestrian Corridor on

 (Rapid Transit - Red Line) Mezzanine Level

 GCRTA Brookpark Pedestrian Corridor Leading

 (Rapid Transit - Red Line) to Platforms

 SEPTA 8th Street Pedestrian Overpass

 (Rapid Transit - Blue Line) Connecting Eastbound and

 Westbound Platforms

 3-4

Click HERE for graphic.

 3-5

Click HERE for graphic.

 3-6

Click HERE for graphic.

 3-7
 Installation Conditions-Boston

 Detectable Warning Materials

 Outdoor-MBTA Blue Line, Orient Heights Station, Outbound Platform

 Indoor-MBTA Red Line, South Station, Mezzanine Level Walkway

Pre-installation

 - Fill out MBTA Permit to Visit and General Release

 - Attend safety orientation - rapid transit

Installation at Orient Heights

- Work hours

 - 1:00 am to 5:00 am weekdays and Saturday

 - 1:00 am to 6:00 am Sunday

 - Materials and equipment can be moved onto platform

 starting at 12:00 midnight

 - All materials and equipment to be removed and area to be

 broom clean at end of work hours

- Station access for equipment

 - Station is at grade level, entry through 4-foot wide gate

- Utilities available

 - Electric power-120 volt, 15 amp power; contractor to

 provide extension cords

 - Water-available from a washroom; contractor to supply

 hose or bucket

 - Restrictions on use of gasoline-powered equipment: none

- Platform description

 - Platform depth: 7 inches

 - Rebar depth is greater than 2 inches

 - No metal edge or bumper at platform edge

 - Platform condition: Good-minimal spalling or cracking

 Figure 3-1

 Specification Sheet for Orient Heights Station

 3-8

The installations extended over a much longer period than

originally planned. This was due to a combination of several
factors. First, the selection of installation dates was delayed

for certain manufacturers whose in-house installers were occupied

by other projects, or who needed extra time to hire a local

contractor. The delays led to the postponing of installations from

the fall of 1993 to the winter of 1993-1994. During the winter the

abundance of snow, rain, and extreme cold caused further delays.

The staggered installation dates meant that various materials had

different exposure periods to passenger traffic and weather, for

example, the exposure period for materials installed in December

was longer than the exposure period for materials installed in the

following February. The evaluation process accounts for the time

exposure variable, and the presentation of performance results for

each material always includes the number of exposure days.

Six of the participating manufacturers were able to install their

products at two transit systems, while the other two were able to

install only at one system. Most manufacturers were unwilling to

install at all three transit systems due to the cost. In addition,

because of the weather delays, certain manufacturers that had

planned to install at all three transit systems were not able to

schedule the full set of installations. Table 3-4 lists the

completed test installations, at both the indoor and outdoor test

sites at each system.

In addition to observation and data collection, the on-site project

staff monitor at each installation acted as a facilitator, working

with transit system staff to resolve any unexpected problems. 

These included: changes in installation time windows, obtaining

extra time for the setting of adhesives used in the bonding of

materials to the station surface, obtaining flagger services, and

ensuring access to utilities.

3.2 FIELD TEST RESULTS

The results of the field tests of the detectable warning materials

are presented in two parts:

 - Qualitative information and photographs illustrating the

 condition of the material and the installation after a

 specified number of days of exposure.

 - Quantitative data on the wear resistance of the materials

 based on the measurement of dome heights at the indoor

 "accelerated wear" test section.

 3-9
 Table 3-4

 Completed Test Installations

MANUFACTURER INDOOR OUTDOOR

PRODUCT NAME

 MBTA GCRTA SEPTA MBTA GCRTA SEPTA

ADA Consultants X X

Alert Mat

Carsonite International X X X X

Pathfinder

Crossville Ceramics X X X

Tac-Tile

Engineered Plastics X X X X

Armor-Tile

Hastings Pavement X X

ADA Paver

Rehau X X X

Access Tactile Tile

Summitville Tile X X

Tactile Tread

Transpo Industries X X X X

Step-Safe

 3-10

3.2.1 Field Test Results - Condition of the Material and

 Installation After Exposure

At each field test site there were at least two sets of

observations and photographs recorded in order to determine changes

in the condition and performance of each material. The first set

of observations and photographs were taken immediately after the

installation was complete. These measurements served as the

baseline for the initial material/installation condition and visual
appearance. The last set of observations was made at the latest

possible date allowed by the evaluation time schedule (May/June

1994) in order to allow the maximum exposure time for all

installations. The specific dates for each test installation

measurement and the number of exposure days for each material is

cited as part of the results. Appendix C displays the form used to

collect data during the observation visits to each test site.

The specific observations and photographs recorded include the

following condition and performance factors:

 - Cracking and chipping of the material.

 - Lifting edges or bubbles under the material.

 - Problems with mechanical fasteners.

 - Discoloration of the surface.

 - Integrity of the installation.

The field test results on material and installation condition are

presented for each transit system. The results for each transit

system include the number of exposure days for each material and a

brief description of some typical problems encountered. 

Photographs are used to illustrate specific problems of material

conditions.

A summary section presenting a comprehensive overview of the

condition of each material and installation follows the transit

system descriptions and photographs.

 3-11

3.2.1.1 MBTA - Table 3-5 lists the test installations at the

Orient Heights station (outdoor) and at South Station (indoor),

along with the number of days of exposure for each material, as of

June 1, 1994. The two Boston sites had the greatest number of

installations, with seven materials at South Station and six

materials at Orient Heights.

In terms of ridership, South Station was the most heavily used

indoor station in the test program. The materials installed at

South Station were subject to the most foot traffic.

The Orient Heights station was the busiest of the test program's

outdoor sites. In addition, four of the six materials were in

place during a particularly cold and snowy winter. This provided a

good initial test for their performance in an outdoor setting.
Some typical results of exposure are shown in Figure 3-2, which

presents a photograph of the installation of Rehau's Access Tactile

Tile at South Station. One of the tiles has completely lifted off

the surface. Complete results for this material and all other

materials are presented in the field test summary section..

Figure 3-3 shows a portion of the installation of Transpo's StepSafe at Orient Heights. One tile has cracked and is no longer

bonded to the platform.

 3-12

 Table 3-5

 MBTA Test Installations

 MANUFACTURER EXPOSURE DAYS (AS OF JUNE 1, 1994)

 PRODUCT NAME

 ORIENT HEIGHTS SOUTH STATION

 (OUTDOOR) (INDOOR)

Carsonite International 177 179

Pathfinder

Crossville Ceramics 14 121

Tac-Tile

Engineered Plastics 165 164

Armor-Tile

Hastings Pavement Not Installed* 141

ADA Paver

Rehau 36 78

Access Tactile Tile

Summitville Tile 161 167

Tactile Tread

Transpo Industries 168 167

Step-Safe

* Material too thick for installation on platform.

 3-13
Click HERE for graphic.

 3-14

Click HERE for graphic.

 3-15

3.2.1.2 GCRTA - Table 3-6 lists the test installations at the

Triskett Street station (outdoor) and at the Brookpark station

(indoor), along with the number of days of exposure for each

material, as of May 23, 1994. Of the six test sites, these two

sites had the longest exposure to passenger traffic, maintenance

and cleaning, and weather. The final set of measurements and

observations at the Cleveland stations took place nearly seven

months after completion of the installation of the materials.

The ridership at the two stations was much lower than the ridership

at the MBTA stations or at SEPTA's 8th Street station. The

resulting wear that took place at Triskett and Brookpark may be

typical of the wear that takes place at stations of small- and

medium-size rail systems, or low-use stations of larger rail

systems.

Selected results demonstrate a change in the color of ADA

Consultant's Alert Mat installation at Brookpark after 200 days of

exposure as shown (see Figure 3-4). The sample piece in the center

is a portion of the material that was not installed.

Figure 3-5 displays a portion of the Transpo Industries' Step-Safe

installation at Triskett Street. Notice the three chipped domes

along the bottom row.

 3-16

 Table 3-6

 GCRTA Test Installations
 MANUFACTURER EXPOSURE DAYS (AS OF MAY 23, 1994)

 PRODUCT NAME

 TRISKETT STREET BROOKPARK

 (OUTDOOR) (INDOOR)

ADA Consultants 200 201

Alert Mat

Carsonite International 201 202

Pathfinder

Hastings Pavement Not Installed* 200

ADA Paver

Transpo Industries 200 201

Step-Safe

* Material too thick for installation on platform

 3-17

Click HERE for graphic.

 3-18

Click HERE for graphic.

 3-19

3.2.1.3 SEPTA - Table 3-7 lists the test installations at

Bethayres station (outdoor) and at the 8th Street station, along

with the number of days of exposure for each material, as of May

20, 1994.

Many of the manufacturers who had already installed their products

for evaluation at MBTA and GCRTA did not carry out installations at

the last site. For this reason, as shown in Table 3-7, there were
only three materials tested at 8th Street and one material at

Bethayres.

Selected results include the display of a portion of Rehau's Access

Tactile Tile installation at 8th Street (see Figure 3-6). The

caulking at the bottom edge has begun to loosen from both the tile

and the platform surface.

Figure 3-7 displays a portion of Engineered Plastics' Armor Tile

installation at Bethayres. There is some accumulated dirt and sand

but no visible chipping or adhesion problems.

 3-20

 Table 3-7

 SEPTA Test Installations

 MANUFACTURER EXPOSURE DAYS (AS OF MAY 23, 1994)

 PRODUCT NAME

 BETHAYRES 8TH STREET

 (OUTDOOR) (INDOOR)

Crossville Ceramics Not Installed* 40

Tac-Tile

Engineered Plastics 87 86

Armor-Tile

Rehau Not Installed* 113

Access Tactile Tile

* Due to cold temperature conditions

 3-21

Click HERE for graphic.

 3-22
Click HERE for graphic.

 3-23

3.2.2 Summary of Field Test Results - Condition of Materials

 and Installation

Tables 3-8 through 3-15 provide a summary of the field test results

for each material based on a compilation of the observations made

during site visits. The summary for each product includes the

following information:

 - Station(s).

 - Installation size(s).

 - Days of exposure.

 - Observations.

The observations for each material are grouped by either outdoor or

indoor installation. The observations note conditions such as:

 - Visible wearing of the domes or base.

 - Cracks and chips in the material.

 - Changes in color.

 - Accumulation of dirt.

 - Loosening of tiles or fasteners.

 - Loss of adhesives.

These observations, along with the analysis of the dome wear at the

indoor installations, form the basis for the performance assessment

of the materials presented in Section 4.

 3-24

 Table 3-8

 Performance of Installed Materials

 ADA Consultants

 "Alert Mat"

OUTDOOR INSTALLATION(S):
 Station: GCRTA Triskett

 Size: 24' x 2' (yellow); 12' x 2'(black)

 Exposure Days (as of May 23): 200

 Observations:

 1. Base surface has many cracks along inside edge of installation.

 2. Yellow mats have faded considerably.

 3. Nearly all fasteners are rusted.

 4. Large air bubbles under 2 (of 4) yellow mats.

 5. Yellow mats can be easily pried off platform using fingers.

INDOOR INSTALLATION(S):

 Station: GCRTA Brookpark

 Size: 8' x 3'4"

 Exposure Days (as of May 23): 201

 Observations:

 1. Domes are smoothest of the four materials installed at

 Brookpark.

 2. Mats have accumulated much dirt; original yellow color is

 hardly visible.

 3. About three-fourths of fasteners are rusted.

 3-25

 Table 3-9

 Performance of Installed Materials

 Carsonite International

 "Pathfinder"

OUTDOOR INSTALLATION(S):

 Station: GCRTA Triskett

 Size: 12' x 2'

 Exposure Days (as of May 23): 201

 Station: MBTA Orient Heights

 Size: 30' x 2'

 Exposure Days (as of June 1): 177
 Observations:

 1. (BOTH) Cracks spreading from many fastener domes.

 2. (GCRTA) Some chipped domes along inside edge of installation.

 3. (BOTH) Dirt has accumulated on fastener caps.

 4. (BOTH) Air pocket under several panels.

INDOOR INSTALLATION(S):

 Station: GCRTA Brookpark

 Size: 8' x 2'

 Exposure Days (as of May 23): 202

 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 179

 Observations:

 1. (BOTH) Visible wear on domes: many textured domes are now smooth.

 2. (BOTH) Dirt has accumulated on fastener caps.

 3. (BOTH) Lip of installations are noticeably higher than

 adjoining surface.

 3-26

 Table 3-10

 Performance of Installed Materials

 Crossville Ceramics

 "Tac-Tile"

OUTDOOR INSTALLATION(S):

 Station: MBTA Orient Heights

 Size: 20' x 2'

 Exposure Days (as of June 1): 14

 Observations:

 1. "A" and "B" tiles not alternating: improper dome spacing.

 2. No wear problems to date.

INDOOR INSTALLATION(S):
 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 121

 Station: SEPTA 8th Street

 Size: 7' x 2'

 Exposure Days (as of May 20): 41

 Observations:

 1. (MBTA) "A" and "B" tiles not alternating: improper dome

 spacing.

 2. (BOTH) Dull yellow color.

 3. (BOTH) No signs of wearing or chipping.

 3-27

 Table 3-11

 Performance of Installed Materials

 Engineered Plastics

 "Armor-Tile"

OUTDOOR INSTALLATION(S):

 Station: MBTA Orient Heights

 Size: 30' x 2'

 Exposure Days (as of June 1): 165

 Station: SEPTA Bethayres

 Size: 9'5" x 2'

 Exposure Days (as of May 20): 87

 Observations:

 1. (SEPTA) One chipped dome.

 2. (SEPTA) Fastener caps have faded in color.

 3. (MBTA) Sand has accumulated among base nubs.

 4. (MBTA) "Newest" looking installation at Orient Heights.

INDOOR INSTALLATION(S):

 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 164
 Station: SEPTA 8th Street

 Size: 7' x 2'

 Exposure Days (as of May 20): 86

 Observations:

 1 . (BOTH) Installations have accumulated sand and dirt more

 than other materials.

 2. (BOTH) No signs of chipping or fading.

 3-28

 Table 3-12

 Performance of Installed Materials

 Hastings Pavement

 "ADA Pavers"

OUTDOOR INSTALLATION(S):

 Station: NONE

INDOOR INSTALLATION(S):

 Station: GCRTA Brookpark

 Size: 8' x 2'

 Exposure Days (as of May 23): 200

 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 141

 Observations:

 1. (BOTH) Chips along edges of individual pavers: occurred

 at installation.

 2. (BOTH) Pavers have turned to grayish-brown color.

 3. (GCRTA) Pit marks throughout installation, both base and

 domes.

 4. (MBTA) White flecks show on surface that were not

 apparent at installation.

 3-29
 Table 3-13

 Performance of Installed Materials

 Rehau

 "Access Tactile Tile"

OUTDOOR INSTALLATION(S):

 Station: MBTA Orient Heights

 Size: 31' x 2'

 Exposure Days (as of June 1): 36

 Observations:

 1. Several tiles are lifting off platform.

 2. Caulking around edge of installation (track side and

 inside) is coming off in several locations.

INDOOR INSTALLATION(S):

 Station: SEPTA 8th Street

 Size: 7' x 2'

 Exposure Days (as of May 20): 113

 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 78

 Observations:

 1. (MBTA) One tile has come off completely.

 2. (MBTA) Most caulk around edges is gone or tearing off.

 (SEPTA) Caulk is beginning to tear off.

 3. (SEPTA) Lifting of several tiles.

 4. (MBTA) More noticeable accumulation of dirt and grime

 compared to other installations.

 3-30

 Table 3-14

 Performance of Installed Materials

 Summitville Tile

 "Tactile-Tread"

OUTDOOR INSTALLATION(S):
 Station: MBTA Orient Heights

 Size: 30' x 2'

 Exposure Days (as of June 1): 161

 Observations:

 1. Three cracks, perpendicular to track, all aligned with

 foundation cracks.

 2. One crack, perpendicular to track, aligned with expansion

 joint.

 3. One chipped dome.

 4. Dirty, but no discoloration.

INDOOR INSTALLATION(S):

 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 167

 Observations:

 1. No signs of wearing; no chips.

 2. Little accumulation of dirt.

 3-31

 Table 3-15

 Performance of Installed Materials

 Transpo Industries

 "Step-Safe"

OUTDOOR INSTALLATION(S):

 Station: GCRTA Triskett

 Size: 20' x 2'

 Exposure Days (as of May 20): 200

 Station: MBTA Orient Heights

 Size: 30' x 2'

 Exposure Days (as of June 1): 168

 Observations:

 1. (BOTH) Scraped and chipped domes, both along edges of

 installation and interior domes. These domes reveal

 specks of brownish/rust color - more so at GCRTA.
 2. (MBTA) One tile is completely cracked and can be lifted

 from platform.

 3. (GCRTA) Tiles have faded to several shades of yellow. 

 Several shades of yellow appear on single tiles.

 4. (GCRTA) One tile has hollow sound when stepped on,

 indicating separation from platform.

 5. (MBTA) Base and domes are "pitted."

 3-32

 Table 3-15

 Performance of Installed Materials

 Transpo Industries

 "Step-Safe"

 (Continued)

INDOOR INSTALLATION(S):

 Station: GCRTA Brookpark

 Size: 8' x 2'

 Exposure Days (as of May 23): 201

 Station: MBTA South Station

 Size: 8' x 2'

 Exposure Days (as of June 1): 167

 Observations:

 1. (MBTA) Visible wear on domes: textured tops often worn

 smooth.

 2. (MBTA) Pit marks, similar to Orient Heights installation.

 3. (GCRTA) Epoxy between several sets of tiles is cracking;

 in two cases, epoxy is falling out.

 4. (GCRTA) Epoxy has stuck to tops of about half of tiles. 

 This occurred at installation. There is a greater
 accumulation of dirt on top and adjacent to this epoxy.

 5. (BOTH) Slightly uneven setting of tiles. Not a tripping

 hazard, but locations for accumulation of dirt.

 3-33

3.2.3 Field Test Results - Measurement of Wear Resistance

One of the major interests of the transit industry is the wear

resistance of the various detectable warning material compositions

produced by the manufacturers. The laboratory testing of

detectable warning materials, as discussed in Section 2, showed a

considerable variation in wear resistance.

The wear resistance of the materials used in the field tests was

measured by the change in average dome height. The measurements

were taken on materials installed at the indoor test sites because

each material was exposed to the same foot traffic and

environmental factors (dirt, moisture, salt, and other materials

carried in by passenger/employee use). The indoor test sites were

selected specifically because they were passageways or walkways

where passengers would be restricted to walking on all of the

materials.

Figure 3-8 illustrates the arrangement of detectable warning

materials at the indoor test site at MBTA South Station. 

Passengers walk across all of the test samples placed in the

walkway as they move into and out of the station. Similar test

section arrangements were made for the indoor walkway test sites at

GCRTA and SEPTA.

The initial and final measurements of dome height were completed on

all of the materials at the same time in order to ensure that all

materials were subject to the same number of exposure days over the

same time frame. The initial measurements of dome height were made

immediately after all of the installations were complete. The

final measurements were made at the latest possible date in the

evaluation time schedule in order to accumulate the maximum

exposure time.

Measurements of wear are reported for the indoor installations at

GCRTA and MBTA based on the following number of days of exposure:

 - GCRTA - 198 exposure days (6.6 months)
 - MBTA - 69 exposure days (2.3 months)

Wear measurements for the SEPTA installation are not reported

because the exposure time was too short.

The measurement of wear was based on the change in dome height

between the initial and final measurements. In order to obtain a

reasonably accurate measurement of the changes in height, 64 domes

on each test panel were measured. The initial (nominal) height of

each dome is five millimeters, therefore it was necessary to use a

micrometer for measuring height to an accuracy of 0.01 millimeters.

Measurement details, including the location of all dome height

measurement points, are cited in Appendix D.

 3-34

Click HERE for graphic.

 3-35

Transit systems are concerned with the useful life of a detectable

warning material installed at the station platform edge and not for

an installation in a walkway or passageway. The "accelerated wear"

test section approach was selected because it would ensure that all

materials were exposed to the same concentrated wear conditions. 

In order to provide a more useful comparison of the relative wear

resistance of each of the materials tested, the wear measurements

were converted from the accelerated wear test section numbers to an

equivalent value applicable to the platform edge. The computation

of this conversion or "acceleration" factor is presented in

Appendix D. The acceleration factors, computed using information

supplied by the transit systems are:

 - GCRTA - 15

 - MBTA - 20

For example, an acceleration factor of 15 for GCRTA simply means

that each unit length (foot) of test material in the passageway at

Brookpark handles 15 times more passenger foot traffic than a unit

length (foot) of active platform at that station.

The wear resistance results are presented in terms of the estimated

annual average wear, as measured by the average decrease in height
and expressed as a percentage of the initial height of the dome. 

All wear resistance results presented in this section are

projections for the platform edge based on one year of use. 

Therefore, if a material is reported to wear by 5 percent per year

on average, the domes at the platform edge could be expected to be

one-half or 50 percent of their original height at the end of 10

years, assuming that the measured wear rate remains the same over

that time.

Figure 3-9 presents the projected annual wear rate for the

materials installed at GCRTA's Brookpark station. This is a

relatively low passenger volume station (estimated by GCRTA at 650

riders per day). The annual wear rates range from approximately

0.4 percent to 1.1 percent. This indicates that the wear

resistance of all of these materials is satisfactory. If the

indicated wear rate is consistent over a long term, such as 10

years, the average dome height would only be reduced by 4 to 11

percent.

Figure 3-10 presents similar information on projected annual wear

rates for the seven detectable warning materials installed at the

MBTA South Station site. This station is a high passenger volume

station with an estimated 16,275 passengers per day, approximately

25 times greater than that of the Brookpark station. In this case,

the projected annual percentage wear rate ranges from a low of 0.28

percent to a high of 3.2 percent. The highest wear rate would

result in a 32% average reduction in dome height over a period of

10 years, assuming that the rate remained constant over that

period.

 3-36

It is important to point out that many of the dome wear

measurements demonstrated a significant variation around the

average of mean values cited above; this means that in many

instances certain domes showed little or no wear while others were

considerably more than the average. The details of these

measurement variations are provided in Appendix D. The overall wear

resistance performance of all materials tested was quite

satisfactory when projected to the platform edge application. 

There was, however, a considerable variation in the relative wear

resistance of each material as illustrated in Figures 3-9 and 3-10.

 3-37
Click HERE for graphic.

 3-38

Click HERE for graphic.

 3-39

 4. COMPARATIVE PERFORMANCE OF DETECTABLE WARNING SYSTEMS

This section of the report presents an overall assessment and

comparison of all detectable warning systems that were field tested

at the participating transit systems. The term "detectable warning

system" is used to emphasize the fact that performance is dependent

upon the physical characteristics of each material, the mechanics

and quality of the material bond to the platform substrate, the

surface preparation of the substrate, and the nature and quality of

maintenance efforts to keep the surface clean and free of water,

ice, or snow.

The section is divided into two parts. The first part includes

observations and some general conclusions regarding the detectable

warning installation and maintenance processes. The second part of

the section assesses the performance of each detectable warning

system by comparing and ranking each field test installation using

four performance parameters.

4.1 INSTALLATION AND MAINTENANCE OF DETECTABLE WARNING SYSTEMS

The opportunity to observe approximately two dozen installations

and to monitor their physical condition and appearance over a

period of approximately seven months provides some insights into

the installation and maintenance processes. The observations and

general conclusions derived from this experience may provide some

useful guidance to rail transit system operators and others who are

concerned about the retrofit installation and maintenance of

detectable warning materials on an existing transit station

platform.

4.1.1 Observations and General Conclusions Regarding Installation
Transit systems will consider several factors when selecting a

detectable warning product for their platform edges. In a retrofit

situation, case of installation is one of these factors. Ease of

installation includes: the skills required of the installers; the

tools required for installation; and the ease of replacing worn or

broken portions of the material. An ideal product for retrofit

installation is one which combines ease of installation with a long

useful life and low maintenance costs.

Proper installation of the detectable warning material is crucial

to the performance and durability of the material., This is

particularly true for outdoor installations. The four installation

factors that affect performance and durability of the detectable

warning system are:

 4-1

 - Ambient conditions - include an acceptable temperature

 range, acceptable moisture on the installation surface

 (usually none), and acceptable precipitation (usually

 none).

 - Surface preparation - includes some combination of

 cleaning (with a brush, water, or solvent); sanding;

 cutting an outline of the installation area; and removing

 a sufficient depth of the surface material to allow the

 installed material 'to be flush with the surrounding

 surface.

 - Application of material - includes creating a setting bed

 (if needed) for the material; placing the material in the

 proper position; applying adhesive to the surface or the

 material; and, for certain materials, using mechanical

 fasteners to attach the material to the surface.

 - Setting period - the time required before the installed

 material can sustain passenger traffic.

Based on experience with two dozen separate installations, there

was a substantial variation of skills of the individuals who

performed the work for the manufacturers. The installers could be

placed into three groups:

 - Manufacturers' installers.

 - Manufacturers' marketing staff.

 - Outside contractors.

Some caution should be used when comparing experience with these
test installations to full-scale installations where the installers

are expected to be more experienced and skilled. The installation

experience is presented here as a means of conveying information

about the potential problems that may occur if installers lack the

proper experience and skills.

Two of the eight manufacturers had their own installers perform the

work. Their knowledge of their respective material and

installation procedures was apparent in their work. They had the

proper tools, and they knew the "tricks" of the work. All of their

installations went smoothly.

Three manufacturers had marketing staff conduct the field

installations. Two of these products required few special skills

for installation. Their respective marketing staffs installed the

material without difficulty. Marketing staff from the third

manufacturer knew how to install their product, but they

experienced some difficulties due to problems with the tools they

used in the installations.

Three of the manufacturers (all with "tile" products that are

typically one foot square sections) employed outside contractors to

install their material. Two manufacturers had company staff

supervising the work. All of the outside contractors had

experience in laying

 4-2

tile, and generally they did a good job in the installation. One

installation had difficulty due to epoxy adhesive (at one location)

that was forced out onto the tile surface, likely due to premature

exposure to foot traffic. Another contractor experienced some

initial difficulty in cutting and removing the concrete surface,

presumably due to lack of experience with this procedure.

A less effective job of installing a detectable warning material

may have contributed to a less effective performance of the

material in this field evaluation. This emphasizes the importance

of correct installation. Where applicable, this is noted in the

comparative assessment of materials.

4.1.2 Maintenance of Detectable Warning Systems

All of the field test installations of detectable warning materials

were subject to normal maintenance practices of the three

participating transit systems. For reference, these standard
platform maintenance practices are summarized in Table 3-2, Station

Environment.

In general, there were no reports of any maintenance problems with

any of the test materials during the evaluation period (November

1993 to June 1994). The field test results cited in Section 3

showed that some materials accumulated more sand and dirt than

others. This was not the result of cleaning procedures because all

test materials were subject to the same cleaning method and

frequency.

A major concern of many transit systems located in the northern

parts of the U.S. is the maintenance of detectable warning systems

under winter time conditions. The transit systems were selected to

ensure that all outdoor installation sites were exposed to sun and

precipitation, including accumulations of ice and snow. While each

transit system used slightly different procedures, none of them

encountered any problems in removing ice or snow from the various

detectable warning materials. Each transit system used the same

tools and chemicals on its detectable warning materials as on the

rest of the platform surfaces.

The following is a list of the tools and chemicals used for snow

and ice removal by the three systems:

 - GCRTA: Shovels and salt mixture.

 - MBTA: Shovels, ice chippers, and sand.

 - SEPTA: Shovels, snow blowers, and calcium chloride.

No system reported any difficulties in the removal of ice or snow. 

There was no report of ice or snow getting stuck between domes of a

detectable warning material.

 4-3

Some materials (including both ceramic and composite-based

materials) at the GCRTA and MBTA outdoor installations had chipped

domes. The chips were most likely caused by the banging and

scraping of shovels and ice chippers during ice and snow removal.

None of the cracks in the detectable warning materials installed at

outdoor sites as reported in Section 3 can be directly attributed

to ice and snow removal. However, the presence of rain or melted

ice or snow can lead to problems. If there are gaps between the

tiles of installed material, water can seep in. The water can then

re-freeze, causing cracks or separation of the material from the

platform.
4.2 PERFORMANCE ASSESSMENT

This part of the report provides a performance assessment of the

eight detectable warning systems that have been field tested. The

performance assessment is based on the field test results

consisting of quantitative data measuring wear resistance (see

Section 3) and qualitative information on the condition of the

material and the installation after exposure to passenger traffic

and weather. Consequently the following four categories have been

selected for the assessment of material performance:

 - Resistance to wear.

 - Maintenance of bond with surface.

 - Resistance to cracking and chipping.

 - Maintenance of color.

The first category is a quantitative one and the next three are

based on qualitative information produced through on-site

observations. All four performance categories are important to a

transit system when it is selecting a detectable warning material

for retrofit on its stations' platform edges.

Each test material has been ranked according to its performance in

each performance category. There has been no attempt to determine

an overall ranking combining all four performance categories

because that would require the assignment of relative weight to

each category. It is expected that transit systems will examine

the results in each performance category and make their own

judgement on overall performance and applicability to their system.

4.2.1 Considerations in Interpreting Rankings

The field tests were designed to gather information on the

detectable warning materials that is both relevant to the concerns

of transit systems and reliable for developing rankings of the

materials on key characteristics. Two features of the field tests

helped to provide relevant and reliable information:

 4-4

 - Side-by-side installation of materials at each of the six

 sites (as many as seven materials at one site).

 - Exposure of these materials to daily revenue service, at

 both indoor and outdoor sites.

It is important to note that the performance rankings presented
here are based strictly on the measured and observed data and

information from the field test. Issues that a transit system

should consider when reviewing the rankings include the following:

 - The abbreviated time frame of the field test evaluation

 limits the scope of observations and data collection. 

 Even with several inspections of each installation site,

 these are only "snapshots" of materials that are exposed

 to pedestrian traffic, weather, and maintenance on a

 daily basis. The time frame issue also relates to the

 difference between the period of exposure for this

 program (up to seven months) versus the manufacturers'

 claims of the materials' lifetimes (five to ten years). 

 It is often difficult to project long-term performance

 using short-term data.

 - Because these are field tests, it is not possible to

 subject each material to identical environmental

 conditions. The materials have been exposed to all

 conditions that come with rail stations in daily use. 

 For example, a single chipped dome at an outdoor

 installation of a material may have resulted from an

 atypically rough attempt by a maintenance worker to

 remove ice from the surface. The rankings de-emphasize

 single, small flaws and focus on systematic problems,

 especially those that occur at more than one

 installation.

 - Three of the rankings rely on engineering judgment of

 qualitative information. The use of standardized forms

 to record observations helped to achieve a high degree of

 consistency in these judgments. In order to insure

 consistency of the data collection process, the number of

 observers was limited to three persons for the

 installations, and only one person conducted the

 subsequent site visits and carried out all dome wear

 measurements. In the wear test, several of the

 components that are used to derive the "acceleration

 factor" are rough estimates based on the judgment of

 transit system staff. However, the resulting

 acceleration factors are applied in the same manner to

 the measured dome height data of all materials;

 therefore, the relative ranking of the materials is

 unaffected.

 - Finally, the quality of the installation of a product has

 a significant influence on the long term performance of

 the material. As much as possible, the rankings take

 into account (based on a review of the available written,
 photographic, and video documentation) performance

 weaknesses that can be directly attributable to problems

 in the initial material installation.

 4-5

4.2.2 Performance Rankings

The tables presented in this section summarize the comparative

performance of the eight detectable warning materials that were

field tested. Each table ranks the performance of the materials

using four categories: wear resistance, bonding with the surface,

resistance to chipping and cracking, and maintenance of color. The

performance levels are:

 1 Best performance, that is, little or no problem

 2 Noticeable but small flaws in performance

 3 Significant performance flaw at one site or consistent

 minor flaws at several sites

 4 Poor performance that raises concern about the usefulness

 of the material installed on a transit station platform

Within each performance level, the manufacturers are listed in

alphabetical order to indicate that there is little, if any,

difference in performance.

The text for each performance category provides a brief description

of the data and observations that led to the specific ranking of

materials. For more detailed information, see Section 3,

particularly, Tables 3-8 to 3-15 and Figures 3-9 and 3-10.

A summary of the rankings for all materials is presented at the end

of the section.

 4-6

4.2.2.1 Wear Resistance - Table 4-1 rates performance of the

eight materials installed in The field test sites by the resistance

to wear of the materials. No material was judged to have poor

performance. As noted earlier in Section 3.2.3, "Field Test
Results--Measurement of Wear Resistance," all of the materials were

estimated to have a relatively long useful life for the platform

edge application. The third ranking was given to the material that

showed the highest wear at Brookpark (ADA Consultants' Alert Mat)

and to the two materials with the highest wear at South Station

(Carsonite's Pathfinder and Engineered Plastics' Armor-Tile).

 Table 4-1

 Ranking of Materials by Resistance to Wear

 1 Hastings Pavement - ADA Paver

 1 Summitville Tiles - Tactile Tread

 2 Crossville Ceramics - Tac-Tile

 2 Rehau - Access Tactile Tile

 2 Transpo Industries - Step-Safe

 3 ADA Consultants - Alert Mat

 3 Carsonite International - Pathfinder

 3 Engineered Plastics - Armor-Tile

1 Best performance, little or no problem 

2 Small flaws in performance 

3 Significant flaw at 1 site or consitent minor flaws at several sites

4 Poor Performance

 4-7

4.2.2.2 Maintenance of Bond with Platform Surface - Table 4-2

rates performance of the eight materials installed in the field

test sites by the maintenance of bond of the materials to the

platform surface. The performance of the materials varied greatly

in this category. Four of the eight materials showed no problem

with their adhesion to the surface. In two instances Transpo's

Step-Safe underwent some loss of bond between individual tiles and

the surface. Observation of Carsonite International's Pathfinder

at two different sites revealed air pockets under several panels. 

The two products rated as poor performers exhibited significant

problems including complete loss of adhesion and large air bubbles

under the mat.

 Table 4-2
 Ranking of Materials by Maintenance of Bond with Surface

 1 Crossville Ceramics - Tac-Tile

 1 Engineered Plastics - Armor-Tile

 1 Hastings Pavement - ADA Paver

 1 Summitville Tiles - Tactile Tread

 2 Transpo Industries - Step-Safe

 3 Carsonite International - Pathfinder

 4 ADA Consultants - Alert Mat

 4 Rehau - Access Tactile Tile

1 Best performance, little or no problem 

2 Small flaws in performance 

3 Significant flaw at 1 site or consitent minor flaws at several sites

4 Poor Performance

 4-8

4.2.2.3 Resistance to Chipping and Cracking - Table 4-3 rates

performance of the eight materials installed in the field test

sites by the resistance of the materials to chipping and cracking. 

No material was judged to have poor performance. Two materials

(Crossville's Tac-Tile, Rehau's Access Tactile Tile) had no chips

or cracks in any of their test installations. The next four

materials had a few chips or cracks but no pattern of problem in

this performance category. The last two materials had repeated

instances of cracked domes (Transpo's Step-Safe at two outdoor

locations) and cracks along its base surface (ADA Consultant's

Alert Mat at the outdoor installation).

 Table 4-3

 Ranking of Materials by Resistance to Chipping and Cracking

 1 Crossville Ceramics TacTile
 1 Rehau Access Tactile Tile

 2 Carsonite International Pathfinder

 2 Engineered Plastics ArmorTile

 2 Hastings Pavement ADA Paver

 2 Summitville Tiles Tactile Tread

 3 ADA Consultants Alert Mat

 3 Transpo Industries - Step-Safe

1 Best performance, little or no problem 

2 Small flaws in performance 

3 Significant flaw at 1 site or consitent minor flaws at several sites

4 Poor Performance

 4-9

4.2.2.4 Maintenance of Color - Table 4-4 rates performance of the

eight materials installed in the field test sites by the

maintenance of color of the materials. Three materials showed no

color changes, either at indoor or outdoor sites. Carsonite

International's Pathfinder had some fading around its fastener

domes; Rehau's Access Tactile Tile color changes were due to the

greatest retention of dirt and grime of any test material at each

of its installation sites. Hastings Pavement's ADA Paver and

Transpo's Step-Safe both revealed flecks of different colors on

their tiles not visible at installation. ADA Consultants' Alert

Mat showed major color changes at both its indoor and outdoor

installations. At the indoor station the Alert Mat product

appeared to absorb dirt and changed from a bright yellow to a grey

mottled color, while at the outdoor station the product turned to a

grey-green color.

 Table 4-4

 Ranking of Materials by Maintenance of Color

 1 Crossville Ceramics TacTile

 1 Engineered Plastics ArmorTile
 1 Summitville Tiles Tactile Tread

 2 Carsonite International Pathfinder

 2 Rehau Access Tactile Tile

 3 Hastings Pavement ADA Paver

 3 Transpo Industries - Step-Safe

 4 ADA Consultants Alert Mat

1 Best performance, little or no problem 

2 Small flaws in performance 

3 Significant flaw at 1 site or consitent minor flaws at several sites

4 Poor Performance

 4-10

4.2.2.5 Summary of Rankings - Table 4-5 presents a summary of

rankings for all performance categories. The eight manufacturers

are listed alphabetically. As noted earlier in this section of the

report, there is no weighting of the characteristics, nor is there

a composite ranking to determine the overall best material.

 Table 4-5

 Summary of Performance Ranking

 CHIPPING

 WEAR BONDING CRACKING COLOR

ADA Consultants Alert Mat 3 4 3 4

Carsonite International Pathfinder 2 3 2 2

Crossville Ceramics TacTile 2 1 1 1

Engineered Plastics ArmorTile 3 1 2 1

Hastings Pavement ADA Paver 1 1 2 3

Rehau Access Tactile Tile 2 4 1 2

Summitville Tiles Tactile Tread 1 1 2 1
Transpo Industries - Step-Safe 2 2 3 3

1 Best performance, little or no problem 

2 Small flaws in performance 

3 Significant flaw at 1 site or consitent minor flaws at several sites

4 Poor Performance

 4-11

 5. SUMMARY OF NATIONAL IMPLEMENTATION PANEL ACTIVITIES

The National Implementation Panel for Detectable Warnings was

established as a separate entity under the FTA Detectable Warnings

Program for the following purposes:

 - Provide input and guidance on the overall FTA-sponsored

 research and test activities regarding detectable

 warnings.

 - Review the findings of the human factors research and the

 engineering tests and evaluation.

 - Make recommendations and provide information that will

 assist the transit industry in the selection and

 installation of detectable warning systems at transit

 station platform edges.

The activities of the Panel and its achievements are described in

Reference 6. This section of presents information exchanged through

the Panel meetings regarding transit system experience with

detectable warning procurement and installation. This information

complements the results of the testing and performance assessments

reported in the preceding sections of the report.

5.1 PANEL COMPOSITION

The Panel was comprised of individuals who are members of diverse

constituencies that have an immediate stake in the implementation

of detectable warnings. Panel Members include transit personnel

with direct responsibility for detectable warnings installation,

persons with disabilities, a representative of a prominent senior

citizen's organization, and experts in disability policy and

practice. Table 5-1 lists the Panel Members and their
organizational affiliations.

The Panel was assisted by a group of Panel Observers, selected for

their technical knowledge and experience with detectable warnings. 

Panel Observers included technical representatives from the Federal

Transit Administration (FTA), a representative of the American

Public Transit Association (APTA), technical staff from the Volpe

Center, and representatives of the three transit systems

participating in the field tests of detectable warning systems. 

Panel Observers also included technical research staff from

Technology & Management Systems, Inc. (TMS), and Boston College. 

Table 5-2 lists the Panel Observers and their organizational affiliations.

 5-1

 Table 5-1

National Implementation Panel for Detectable

 Warnings Panel Member List

Robert Beck Walter Noonan

Long Island Railroad New York City Transit Authority

George Fleisher, M.D. Dona Sauerburger

Department of Rehabilitation Medicine Volunteers for the Visually

St. Vincent's Medical Center Hnadicapped

 

Margaret Groce Marilyn Saviola

New York City Public Schools New York Center for the

Travel Training for the Handicapped Independence of the Disabled

Geraldine Kelley Nicholas Scarano

New York City Public Schools Metro North Commuter Railroad

Educational Vision Programs and 

Services Rolf Skogland

 Port Authority of NY and NJ

 Journal Square Transportation Center

Gertrude Landau 

New York Citizen's Committee on Aging Ralph Weule

 Safety & Investigations

Karen Luxton- Gourgey, Ph.D. San Francisco Bay Area Rapid Transit

Computer Center for the Visually District

Impaired

City University of New York 

Harry Nagy

Office of Special Services

New Jersey Transit
 5-2

 Table 5-2

 National Implementation Panel for Detectable Warnings

 Panel Observer List

Billie Louise Bentzen William Hathaway

Accessible Designs for the Blind Volpe National Transportation

Boston College Systems Center

William H. Bregoli, Jr. H. Norman Ketola

Massachusetts Bay Transportation Technology & Management

Authority Systems, Inc.

 

David Capozzi (invited) Carol H. Lavoritano

Architectural and Transportation Southeastern Pennsylvania

Barriers Compliance Board Transportation Authority

Vincent R. DeMarco Ramon A. Lopez

Federal Transit Administration Federal Transit Administration

 Patricia Ryan

Deborah L. Dubin Volpe National Transportation

American Public Transit Association Systems Center

John P. Goodworth Robert W. Stout

Greater Cleveland Regional Transit Federal Transit Administration

Authority

 5-3

The Panel was established in the fall of 1993. Panel activities were

organized and facilitated by the American Foundation for the Blind (AFB). 

AFB also conducted a national review of the experience of transit systems and

transit users with detectable warnings. The purpose of this national

information collection effort was to obtain the reactions of people in "key

stakeholder" groups about issues that had been raised in the rulemaking

process on detectable warnings at transit platform edges. A total of fiftyfour persons in thirteen states were interviewed by telephone. The results

are presented in Reference 6.

5.2 PANEL ACTIVITIES
The first Panel meeting took place on December 3, 1993, at AFB's National

Headquarters in New York City at which time the Panel reviewed the results of

the national information collection effort. The Panel also framed the

critical issues it wished to address and heard reports describing detectable

warnings performance at the Bay Area Rapid Transit System (BART), human

performance testing of detectable warnings, and plans for engineering testing

and field evaluations of detectable warnings installations to be carried out

during the winter of 1993 - 1994. Panel Members participated in an

implementation scenario exercise to prepare for detectable warnings

implementation. The first Panel meeting reached the following conclusions:

 - The issues related to detectable warnings were a matter of serious

 concern. Panel Members acknowledged the emotional nature of the

 topic and expressed mutual respect for each other's concerns.

 - The cost of detectable warnings implementation was a serious

 matter, although the Panel viewed cost as secondary to transit

 system safety and access, a fundamental responsibility of transit

 systems. The Panel stressed that all transit infrastructure costs

 were "big ticket items" and detectable warnings fit into this

 category.

 - There was a critical need to gather and disseminate accurate

 information about detectable warnings in the transit industry and

 disability communities.

 - Detectable warnings should be viewed as a transit design element

 that was beneficial to the safety of all passengers.

The second Panel meeting was held on May 11, 1994, at AFB's National

Headquarters in New York City. At this meeting the Panel reviewed the

findings of the engineering laboratory testing and interim results of the

field evaluations of detectable warnings carried out at the three transit

properties during the winter of 1993 - 1994. The Panel also heard reports

about the experiences of eight transit systems involved in detectable

warnings installation and testing and developed the blueprint and content for

a detectable warnings implementation document.

 5-4

5.3 SUMMARY OF TECHNICAL INFORMATION FROM THE PANEL

This section provides a summary of the technical information and guidance

provided by the Panel Members and Panel Observers that has a direct bearing

on the needs of the transit industry with regard to the selection,

procurement, installation, and maintenance of detectable warning systems. 
The information is organized into two categories as follows:

 - Experiences with detectable warning materials procurement and

 installation.

 - Tips for implementing detectable warning requirements.

5.3.1 Experiences with Detectable Warning Procurement and Installation

Panel Members and Observers during the panel meetings presented a series of

observations related to their experiences with the procurement and

installation of detectable warning systems. These observations are provided

here for purposes of information; however, it should be noted that they do

not cover all aspects of selection, procurement, and installation.

 - A number of systems have conducted laboratory tests or limited

 field tests of detectable warning materials that provide additional

 sources of information to the transit industry.

 - Most transit systems have to develop their own specifications for

 detectable warning materials and installations in order to

 accommodate the wide variety of station platform construction

 materials and platform physical conditions.

 - Transit platform surface conditions and preparation required should

 be specifically described in the specifications to avoid disputes

 and additional costs when installation is underway.

 - A number of transit systems have chosen to provide detectable

 warnings procurement and installation as part of a general

 contractor's task to bring a complete station into ADA compliance. 

 This approach appears to have created problems when the general

 contractor is able to select one of a number of materials that meet

 the specification. Disputes and legal action have been initiated

 by manufacturers whose products meet the specifications but are not

 selected by the general contractor.

 - Transit systems that contracted with a manufacturer for the

 procurement and installation of a specific detectable warning

 material in a single integrated contract, generally, reported

 prompt and satisfactory progress on system installation.

 5-5

 - One transit system expressed a concern about the limited

 availability of installation contractors which effectively hampered

 competition and precluded the selection of manufacturers whose

 products were completely acceptable but who lacked the capacity to

 carry out effective installations.
 - Installation is a challenging task at most transit systems

 requiring much of the work to be completed during late night and

 early morning hours. Special track use must be arranged to isolate

 specific platforms. Work must be performed on separate halves to

 avoid putting a station out of service due to unanticipated

 installation problems.

 - One transit system placed a patent release clause in its contract

 to preclude future problems when the time came for product

 replacement. This clause allows the system to solicit competitive

 bids for an identical product.

 - One transit system decided not to use mechanical fasteners at

 outside stations because of a concern that a salt mixture used in

 the winter would penetrate the fastener holes, weaken the concrete

 platform steel reinforcement bars, and threaten platform structural

 integrity.

 - Other transit systems were concerned about bonding materials

 completely to the platform that would prevent easy removal and

 replacement of damaged sections. They opted, instead, for

 removable mechanical fasteners and edge bonding.

 - Most systems noted that preparation of substrate and careful

 installation is critical in order to avoid future problems with the

 installation.

 - One transit system left a drainage gap of two inches for every ten

 feet of platform length to avoid accumulation of water under the

 material.

 - One transit system had its station maintenance staff visit other

 systems to collect detailed information on material cleaning

 techniques in order to develop their own detectable warning

 cleaning and maintenance procedures.

 - Removal of snow and ice from detectable warnings can be

 accomplished using routine snow and ice removal procedures

 (shoveling, plowing, and chemical treatment). Ice that accumulates

 between the raised domes can be readily treated with calcium

 chloride (preferable to sodium chloride) as a standard part of

 routine winter maintenance.

 5-6
5.3.2 Tips for Implementing Detectable Warning Requirements

In addition to relating the specific experiences of participating transit

systems, the Panel also tried to generalize their experiences as a series of

recommendations or implementation tips. The following items provide a

summary of some of the key tips:

 - Transit systems should view a retrofit installation of detectable

 warnings as the installation of a "system" that includes the

 detectable warning material itself, the adhesion and/or mechanical

 fastening materials utilized, and the substrate on which the

 warnings are applied.

 - Transit systems should explore the range of materials and

 installation options available when planning to install detectable

 warnings. Costs for procurement, installation, and maintenance

 should be based on consideration of the "detectable warning

 system."

 - Transit systems should contact other transit systems that have had

 experience with detectable warnings to learn about the "track

 record" of their materials and installations.

 - Transit systems should plan carefully for the operational impact of

 the installation process by contacting other systems to learn about

 their experiences.

 - Installing detectable warnings is new for many contractors. 

 Transit systems that have begun the installation process report

 that installations carried out by inexperienced contractors have

 taken longer than anticipated.

 - Transit systems should create a working document that is a

 comprehensive internal "game plan" for implementing the detectable

 warnings requirements, identifying:

 - System's specific objectives and time frames (e.g., "will

 complete installations at three key stations by July 26,

 1994").

 - All aspects of the implementation process including facility

 design, contract and procurement administration, engineering

 considerations, maintenance, public education, marketing, or

 any other areas that are relevant to an individual transit

 system.

 - Departments and key individuals involved in each phase of

 implementation process with a time frame for the involvement.
 - Internal constituencies in a transit agency and the external

 community constituencies for marketing and public education. 

 Organizations of and for persons with disabilities, senior

 citizens' organizations, and generic transit

 5-7

 consumer groups such as a "straphangers" association are

 valuable resources for identifying and reaching key

 constituencies.

 - Checklists created for materials specifications, contents of a

 request for proposal and scope of work, installation and

 maintenance procedures, and public education activities will assist

 transit systems in managing the process of detectable warnings

 installation.

 - Transit systems should be aware that often it is difficult to

 distinguish between factual information updates and rumors and that

 accurate information is not reaching the places where it is needed. 

 Information can be obtained from the Federal Transit Administration

 and the Volpe National Transportation Systems Center. Transit

 systems should verify all information they receive regarding

 detectable warnings, especially information conveyed by telephone,

 regardless of how plausible new information may appear.

 - Flexibility with respect to a transit system's current operating

 and maintenance procedures is essential when initiating a

 detectable warnings installation program. This flexibility is

 important, especially at the time of installation of the material,

 to assure that the installation is done correctly. A major reason

 for the failure of a detectable warnings system is poor

 installation, rather than a problem with the detectable warning

 material.

 5-8

 REFERENCES

 1. Bentzen, B.L., et al. Detectable Warnings: Detectability by

 Individuals with Visual Impairments, and Safety and Negotiability

 on Slopes for Persons with Physical Impairments. Cambridge, MA:

 Volpe Center, U.S. DOT. Final Report, Report No. DOT-VNTSC-

 FTA-94-4.
 2. Bentzen, B.L., Nolin, T.L., and Easton, R.D. Detectable Warning

 Surfaces: Color, Contrast, and Reflectance. Cambridge, MA: Volpe

 Center, U.S. DOT. Final Report, Report No. DOT-VNTSC-FTA-94-5.

 3. Bulletin #1: Detectable Warnings. Washington, D.C.: U.S.

 Architectural and Transportation Barriers and Compliance Board. 

 Advisory Bulletin, April, 1994.

 4. Ketola, H.N. and Chia, D. Results of Laboratory Testing of

 Detectable Warning Materials. Burlington, MA: Technology &

 Management Systems, Inc. Technical Memo No. 65-09-1, November,

 1993.

 5. Sandor, L.W. Testing of Tactile Warning Materials. New York:

 Weintraub & diDomenico in association with Vollmer Associates. 

 Test Report prepared for the Metro North Commuter Railroad,

 November, 1993.

 6. Joffee, E. The National Implementation Panel for Detectable

 Warnings: A Detectable Warnings Implementation Document. New York:

 American Foundation for the Blind. Final Report, September, 1994.

 R- 1/2

 APPENDIX A. INFORMATION ON MATERIALS

 INCLUDED IN LABORATORY TESTS

 A-1/A-2

 Detectable Warnings Evaluation Project

 Materials Tested

 ADA Consultants

 "Alert Mat"

Contact Name and Telephone Number:

 Bob Sprouse (919) 872-5330

Material Information:

 Type of Material: Rubber Compound Mat

 Mat Size: 6' x 3'4"; 6' x 2'
 Mat Thickness: 1/8 inch

 Material Color: Yellow, Black

 Adhesive Used?: Yes

 Mechanical Fasteners Used?: Yes

Special Characteristics (if any):

 Base surface of mat is ribbed.

 A-3

 Detectable Warnings Evaluation Project

 Materials Tested

 Advantage Metal Systems

 "Detectable Warning Systems"

Contact Name and Telephone Number:

 Helmut Klohn (508) 580-5177

Material Information:

 Type of Material: Steel or Aluminum Coated with Polymer

 Panel Size: 10' x 2'

 Panel Thickness: 1/8 inch

 Material Color: Yellow

 Adhesive Used?: No

 Mechanical Fasteners Used?: Yes

Special Characteristics (if any):

 A-4

 Detectable Warnings Evaluation Project

 Materials Tested

 Bridgco
 "ADA Path"

Contact Name and Telephone Number:

 Mike Bridgeman (800) 466-4884

 Material Information:

 Type of Material: Polymer Concrete, Molded at Point of

 Installation

 Application Size: 3' x 2' (size of one form)

 Application Thickness: 3/8 inch

 Material Color: Yellow, Red

 Adhesive Used?: No

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 A-5

 Detectable Warnings Evaluation Project

 Materials Tested

 Carsonite International

 "Pathfinder"

 Contact Name and Telephone Number:

 Peter Mileo (800) 648-7974

Material Information:

 Type of Material: 1. Polymer Composite

 2. Synthetic Rubber Compound (not tested)

 Panel Size: 4' x 2'

 Panel Thickness: 1/8 inch

 Material Color: Yellow

 Adhesive Used?: Yes (optional)

 Mechanical Fasteners Used?: Yes

Special Characteristics (if any):

 Textured pattern on top of domes and tile base.

 A-6
 Detectable Warnings Evaluation Project

 Materials Tested

 COTE-L Enterprises

 "Safti-Trax"

Contact Name and Telephone Number:

 Cyrus Fine (201) 836-0733

Material Information:

 Type of Material: Polyurethane Domes with

 "Durabak" Polyurethane Coating

 Application Size: No Standard Size

 Application Thickness: Applied Directly to Surface

 Material Color: Black, Grey

 Adhesive Used?: No

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Domes are attached to base coating at point of installation.

 A-7

 Detectable Warnings Evaluation Project

 Materials Tested

 Crossville Ceramics

 "Tac-Tile"

Contact Name and Telephone Number:

 Barrie Decker (312) 975-9872

Material Information:

 Type of Material: Unglazed Ceramic Tile

 Tile Size: 1' x 1'
 Tile Thickness: 5/16 inch

 Material Color: Yellow

 Adhesive Used?: Setting Bed and Cement

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 "A" and "B" tiles with complementing dome patterns to create proper

spacing of domes.

 A-8

 Detectable Warnings Evaluation Project

 Materials Tested

 Dal-Tile Corporation

 "Detectable Warning Tile"

Contact Name and Telephone Number:

 Larry Kelly (214) 309-4535

Material Information:

 Type of Material: Unglazed Porcelain Tile

 Tile Size: 2-1/16 x 2-1/16" (available in 23-1/2" x

 12-3/4" sheets)

 Tile Thickness: 1/8 inch

 Material Color: "Daffodil", Black, White

 Adhesive Used?: No

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 A-9

 Detectable Warnings Evaluation Project

 Materials Tested

 Engineered Plastics

 "Armor-Tile"

Contact Name and Telephone Number:

 Ken Szekely (800) 682-2525

Material Information:
 Type of Material: Vitrified Polymer Composite

 Panel Size: 1' x 1' or 4' x 2'

 Panel Thickness: 1/8 inch

 Material Color: Yellow

 Adhesive Used?: Yes (optional)

 Mechanical Fasteners Used?: Yes

Special Characteristics (if any):

 Alignment of domes is parallel and perpendicular to flow of travel (not

 45').

 Dome heights are tapered - shorter domes in rows further from platform

 edge. Domes and surface are nubbed.

 A-10

 Detectable Warnings Evaluation Project

 Materials Tested

 Hastings Pavement Co.

 "ADA Pavers"

Contact Name and Telephone Number:

 Donald Kehoe (800) 874-4717

Material Information:

 Type of Material: Concrete Brick

 Paver Size: 1' x 1'

 Paver Thickness: 2 inches

 Material Color: Brownish-Yellow

 Adhesive Used?: Setting Bed and Cement

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Spacing of domes does not conform to regulations.

 A-11

 Detectable Warnings Evaluation Project
 Materials Tested

 High Quality Tactile Systems

 "Tac Strip"

Contact Name and Telephone Number:

 Stacey Arbetter (617) 935-8450

Material Information:

 Type of Material: Polymer Composite

 Panel Size: 10' x 2'

 Panel Thickness: 1/8 inch

 Material Color: Yellow

 Adhesive Used?: No

 Mechanical Fasteners Used?: Yes

Special Characteristics (if any):

 Domes and surface are nubbed.

 A-12

 Detectable Warnings Evaluation Project

 Materials Tested

 Inco Chemical Supply Co.

 "Tactile Warning System"

Contact Name and Telephone Number:

 Murray Goldenberg (800) 752-4626

Material Information:

 Type of Material: Polymer Concrete

 Application Size: No Standard Size

 Application Thickness: Applied Directly to Surface

 Material Color: Yellow

 Adhesive Used?: No

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 A-13

 Detectable Warnings Evaluation Project
 Materials Tested

 NBS/Aware & Concerned Services

 "Detectable Warning Mat"

Contact Name and Telephone Number:

 Craig Benett (800) 655-3780

Material Information:

 Type of Material: Rubber Mat

 Mat Size: 50" x 25"

 Mat Thickness: Applied Directly to Surface

 Material Color: Yellow

 Adhesive Used?: Yes

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 A-14

 Detectable Warnings Evaluation Project

 Materials Tested

 Rehau,lnc.

 "Access Tactile Tile"

Contact Name and Telephone Number:

 Eric Mingo (703) 777-5255

Material Information:

 Type of Material: Thermoplastic Polyurethane

 Tile Size: 6" x 12"

 Tile Thickness: Applied Directly to Surface (1/a inch)

 Material Color: Yellow

 Adhesive Used?: Yes

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Alignment of domes does not conform to regulations.

 A-15
 Detectable Warnings Evaluation Project

 Materials Tested

 Steps Plus, Inc.

 "Detectable Warning Units"

Contact Name and Telephone Number:

 Robert Kopp (315) 446-8050

Material Information:

 Type of Material: Pre-cast Concrete

 Tile Size: 1' x 1'

 Tile Thickness: 1 inch

 Material Color: Yellow, Blue

 Adhesive Used?: No

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Generally not appropriate for retrofit installations.

 A-16

 Detectable Warnings Evaluation Project

 Materials Tested

 Strongwall Systems

 "Strongwarn"

Contact Name and Telephone Number:

 Bill Kokoletsos (201) 445-4633

 Material Information:

 Type of Material: Two-component Polymer Concrete

 Molded at Point of Installation

 Application Size: No Standard Size

 Uses of Variety of Sizes (5' x 1' most

 common)

 Application Thickness: Applied Directly to Surface

 Material Color: Yellow, Blue

 Adhesive Used?: No
 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 A-17

 Detectable Warnings Evaluation Project

 Materials Tested

 Summitville Tile

 "Tactile-Tread"

Contact Name and Telephone Number:

 Peter Johnson (216) 223-1511

Material Information:

 Type of Material: Glazed Porcelain Tile

 Tile Size: 1' X 1'

 Tile Thickness: % inch

 Material Color: Yellow, Tops of Domes are Brown

 Adhesive Used?: Yes (2-part epoxy)

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Spacing of domes does not conform to regulations.

 A-18

 Detectable Warnings Evaluation Project

 Materials Tested

 Transpo Industries

 "Step-Safe"

Contact Name and Telephone Number:

 John Karlson (914) 636-1000
 Material Information:

 Type of Material: Polymer Concrete

 Tile Size: 1' x 1', 2' x 4' (not tested)

 Tile Thickness: 3/4 inch

 Material Color: Yellow

 Adhesive Used?: Yes (2-part epoxy)

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Textured pattern on top of domes.

 A-19

 Detectable Warnings Evaluation Project

 Materials Tested

 Whitacre-Greer

 "Paver"

Contact Name and Telephone Number:

 Richard Dana (216) 823-1610

Material Information:

 Type of Material: Shale Brick

 Brick Size: 4' x 8'

 Brick Thickness: 11/2, 21/4 inches

 Material Color: 4 Shades of Red/Brown

 Adhesive Used?: Setting Bed and Cement

 Mechanical Fasteners Used?: No

Special Characteristics (if any):

 Spacing and alignment of domes do not conform to regulations.

 A-20
 APPENDIX B. INSTALLATION DATA COLLECTION FORM

 Detectable Warnings Evaluation Project

 Field Test Installation

Date ____________________ Manufacturer ___________________

Station _________________ Product ________________________

 outside/inside

Weather (outside installation):

Installation size: Location:

Crew Size:

Tools:

Steps: Start Time: End Time:

Observations:

 B- 1/2

 APPENDIX C. FIELD TEST DATA AND OBSERVATION FORM

 Detectable Warnings Evaluation Project

 Field Test: Performance and Durability Data

Date __________________ Manufacturer ____________________

Station________________ Product _________________________

 outside/inside

(attach photos)

Wear (measured in mm)

 Domes:

 Base:
Change in Slip Resistance:

Chipping, cracking:

Discoloration:

Other observations:

 C-1/2

 APPENDIX D. DOME HEIGHT MEASUREMENTS AND

 COMPUTATION OF WEAR

One of the important quantitative performance measures is the

relative wear of each detectable warning material surface. In

order to determine wear, dome heights were measured for each of the

materials installed at the indoor sites. This task involved

measuring the height, relative to the material's base, of 64

truncated domes-16 clusters of four domes spread across each eightfoot by two-foot test section-to the precision of 0.01 millimeters

using a depth micrometer. The 16 clusters of domes are located at

the same relative locations for each installed material. Figure D1 presents the locations of the measured cluster of domes on the

test installations.

Measurements of dome heights were always made at the same time in

each test section. Two sets of measurements were made with a time

interval of 198 days at GCRTA and 69 days at MBTA. The average

absolute decrease and the percent decrease in dome heights relative

to the initial measurements were computed using the raw data

collected for dome heights. It was also necessary to derive wear

results that considered that the indoor test installations were

subject to "accelerated" wear because of their placement in

passageways with concentrated passenger traffic.

A conversion factor, or acceleration factor, was derived by the

authors to convert the measured dome height wear at the accelerated

wear test section to a projected wear at the platform edge. The

following equation was used to derive the acceleration factor:

 Acceleration Factor = A * B * C * D * E * F * G / H

where,
 A = Number of platform edges at the station.

 B = Number of cars per train during off peak service.

 C = Peak hour car factor: adjustment to account for a

 greater number of cars per train during the peak

 periods. On the MBTA Red Line, an off-peak train

 has four cars; a peak train, six cars. On the GCRTA

 Red Line, an off-peak train has two cars; a peak

 train, three cars.

 D = Number of doorways per car.

 D-1

Click HERE for graphic.

 D-2

 E = Width of a doorway (feet).

 F = Variability of the stopping location of the doorways

 along the station platform. Variability = 1

 signifies that the doorways always open at the same

 locations. Variability of "n" signifies that each

 doorway opens within a section of the platform "n"

 times the width of the doorway.

 G = Proportion of the station's ridership (both boarding

 and alighting) that cross the test installation. 

 Proportion = I signifies that 100% of the passengers

 travel across the test installation in both

 directions.

 H = Width of the test installation (feet).

These following values were used to calculate the acceleration

factors for GCRTA's Brookpark station and the MBTA's South Station:
 Brookpark South Station

 A 2 2

 B 2 4

 C 1.25 1.15

 D 3 3

 E 4 4

 F 2 5

 G 1 1/3

 H 8 8

 Acceleration Factor 15 23

 The values for F are very rough estimates provided by the

transit system staff. The value for G for South Station is also a

rough estimate; the proportion of passengers travelling across the

test installation may well be less than one-third. Consequently,

the value used for South Station's acceleration factor was rounded

to 20.

 D-3

Measured wear at the accelerated wear test section is calculated

directly from the dome height measurements:

Measured Wear =

 [[(Initial Dome Height) - (Final Dome Height)]/

 (Initial Dome Height)] * 100]

Measured wear is expressed as a percent of the initial dome height. 

An average (mean) value of dome wear was computed for each test

section based on measurements from the 64 selected domes. These

average values are reported in this section.

The projected wear (expressed as a percentage) at the station

platform edge was computed as follows:

 Projected Wear = (Measured Wear) / (Acceleration Factor)

In order to make the projected wear values more readily

understandable, they were converted to annual estimates as follows:

Projected Annual Dome Wear =

 [(Projected Wear) * 365 ]

 ------------------------------------------------------
 (Exposure Days Between Initial and Final Measurements)

All of the wear rates are expressed as dome height decrease as a

percentage of the original dome height.

Tables D-1 and D-2 present the measured and the projected annual

dome height wear values (percentage of initial dome height) for the

materials installed at Brookpark and South Station, respectively. 

The tables also provide a range of projected annual wear rates

based on the variation in the individual dome height wear

measurements. This can be considered as the potential variability

of dome height wear.

 D-4

 Table D-1

 Measured and Projected Dome Height Wear - Brookpark

A. Exposure Days Between Measurements 198

B. Acceleration Factor 15

 RANGE OF PROJECTED

 MEASURED WEAR PROJECTED ANNUAL ANNUAL WEAR 

MANUFACTURER (PRESENT OVER EXPOSURE WEAR AT PLATFORM RATES (BASED ON 

PRODUCT NAME PERIOD) EDGE (PERCENT) VARIABILITY

 MEASURED DATA)

ADA Consultants 8.9 1.1 0.4 to 2.1

Alert Mat

Carsonite, 8.0 0.98 0.4 to 1.4

International

 Pathfinder

Hastings Pavement 3.5 0.42 0.0 to 1.1

ADA Paver

Transpo Industries 6.0 0.74 0.0 to 1.3

Step-Safe

 D-5

 Table D-2

 Measured and Projected Dome Height Wear - South Station
A. Exposure Days Between Measurements 69

B. Acceleration Factor 20

 RANGE OF PROJECTED

 MEASURED WEAR PROJECTED ANNUAL ANNUAL WEAR 

MANUFACTURER (PRESENT OVER EXPOSURE WEAR AT PLATFORM RATES (BASED ON 

PRODUCT NAME PERIOD) EDGE (PERCENT) VARIABILITY

 MEASURED DATA)

Carsonite 11.0 2.9 2.6 to 3.4

International

 Pathfinder

Crossville Ceramics 5.4 1.4 0.0 to 1.8

 Tac-Tile

Engineered Plastics 12.0 3.2 0.3 to 5.1

 Armor-Tile

Hastings Pavement 2.4 0.64 0.0 to 0.8

 ADA Paver

Rehau 5.1 1.3 0.1 to 2.8

 Access Tactile Tile

Summitville Tile 1.1 0.28 0.0 to 2.9

 Tactile Tread

Transpo Industries 2.8 0.74 0.1 to 1.9

 Step-Safe

 D-6

 *U.S. GOVERNMENT PRINTING OFFICE: 1995-600-830/00061