Frequently Asked Questions

  • on Friday, 22 May 2015

Q:What are Tactile Walking Surface Indicators (TWSI’s)?

A: Tactile Walking Surface Indicators (TWSI’s), are devices with defined sets of patterns that have been agreed upon by International Accessibility Experts, that either provide persons with visual impairments a) warning of a hazard or b) following a direction.

Q:Where did Tactile Walking Surface Indicators Originate?

A: Tactile Walking Surface Indicators were originally developed in Japan in the 1960’s when a member of the Royal Household was visually impaired, and every effort possible was initiated to assist this person’s mobility in the public realm. Since then Japan has spearheaded many initiates for assistive devices, and TWSI’s are still more common than anywhere else in the world.

Q: How do Tactile Walking Surface Indicators help people with visual impairments?

A: There are varying degrees of visual impairment, and Tactile Walking Surface Indicators can help in many ways.
For persons with complete loss of vision, they are taught mobility with a “long white cane” or “roller ball cane”. These canes when swiped in a 45 degree arch across the persons path, will allow them to feel a free path ahead. In the case of the “Elongated Bars” or “Way Finding” devise the person will feel the bars, and the direction the length follows and knows this is taking them to a destination. An example would be the sidewalk leading from the Bus/Taxi drop off in front of a Hospital, the bars embedded into sidewalk would lead person to entry doors. On the other hand, if the person detects a series of domes in a regular pattern, this tells them they have reach a “Hazzard” and they must refer to their other training and listen for the traffic, traffic signals or other indicators.
There also exists a much larger portion of our society with various visual impairments who can see contrasts only. In this case TWSI’s can give the first impression to these persons that they can either follow or be cautious.

Q: Where would Tactile Walking Surface Indicators be Used and is there any Legislation for use?

A: Typically most people believe these are used on sidewalk corners only, however under the (Canadian) National Building Code, Tactile Walking Surface Indicators are recommended for use at the top of staircases and landings, edge of transit platforms, top and bottom of ramps, edge of ferry terminal docks, edge of reflecting pools and fountains, both sides of ground-level railway crossings, ground-level moving walkways and all blended curbs.
Ontario has the only current Legislation, under the “Ontarians with Disabilities Act” (AODA) sections 80.26 and 80.27 requires the installation of Tactile Walking Surface Indicators across the bottom of all flat depressed curb crossings. Effective January 1, 2016 this act becomes mandatory and all new construction/repair-replacements will have to conform to this code.

Q: Where have Tactile Walking Surface Indicators Been Used?

A: Starting with Japan in the 1960’s, Tactile Walking Surface Indicators have quickly been adapted around the globe being installed in Australia, New Zealand, Europe and Great Britain, then added in the US during the 1990’s through their ADA and now reaching into Africa and Asia. Currently all are bonded together through the ISO 23599 defining the acceptable grid/dome size and spacing, and providing guidance on luminance.

Q: How Long Should a Tactile Walking surface Indicator Last?

A: As these products have been made in a variety of materials, there have been many questions raised about how long they should last. In the United States because virtually every product had been used in multiple applications, many municipalities where asking what should be expected for their long term investment. The NCHRP (National Cooperative Highway Research Program) has performed extensive research on all these various products and tabled “REPORT 670” which essentially has developed a baseline standard for these products. Because much of the Continental United States experiences winter/snow conditions which demand the use of snow removal equipment, Tactile Walking Surface Indicators in order to deliver any degree of life expediency must be made of materials resistant to snow plow damage. Throughout this report the NCHRP has made reference to the ASSHTO TP 103-13 as the best testing and standards available to determine a reasonable longevity for TWSI products.

Q: Are There Any Products Built/Tested to this Standard?

A: Yes, Distributed by Crozier Enterprises, Neenah Foundry, produces a complete line of TWSI products, built and tested to the ASSHTO Standards, and has shipped hundreds of thousands, without a single unit failing in the field. All products are backed by a 5-year warranty.

Q: How are Neenah Foundry TWSI’s different from the competition?

A: Neenah Foundry and Crozier Enterprises were the first to work closely with MTO to establish a product that would meet all standards as laid out by MTO and the Province of Ontario. The Neenah cast iron TWSI’s are the only currently on the market that fully comply with only Class 35B Cast Iron, where the industry standard even Neenah in the US is only
Class 30. Every casting is clearly marked with manufacturers name, country of origin and year produced on top of casting. Neenah provides two style of product, square and rectangle patent pending quick connect plates which install quickly and efficiently. And like most in the industry a square and rectangle system with radius options which bolt together before installation. Neenah provides with every shipment convenient throw-away hangers that allow the installation process to be done more efficiently. Most notably, the Neenah system provides a more effective range of product, and radius plates with large arch. This means, in over 80% of installations, it takes fewer Neenah plates, meaning a lower cost.

Q: How are Cast Iron TWSI Plates Installed?

A: The Neenah cast iron plates are the easiest in the market to install, finish wet concrete to the point where a broom finish would be applied. Mark the position of installation in the wet concrete, line up the joined plates. Snap the hangers over the plates, and slide a pole or 2x4 through the hangers. Lift plates into position of marks on wet concrete and gently place plates down. Adjust and make sure plate a square, remove hangers and tap plates down until the surface of plate is level with adjacent concrete surface. Wipe off any excess concrete, and concrete that may have come through vent holes, trowel around plates, leave for concrete to dry.

Q: How Do I Order Neenah Cast Iron TWSI’s?

A: Neenah Foundry Plates are distributed by Crozier Enterprises in Canada (excluding British Columbia and Alberta). For further details, call our toll free number at 1.866.624.9722 or email This email address is being protected from spambots. You need JavaScript enabled to view it.