Tactile Warning Surface Indicators (TWSIs) are textured ground surface indicators designed to be felt by foot or with a cane. They are usually made of rubber, concrete, or metal and are installed on sidewalks, transit platforms, and other public spaces. At StrongGo, we build TWSIs primarily to alert visually impaired individuals to potential hazards and guide them to safety.

The Purpose of Tactile Warning Surface Indicators

- Safety: TWSIs are critical in preventing accidents. They warn of upcoming hazards such as street crossings, platform edges, and sudden drop-offs. For example, the distinct raised domes on a platform edge indicate that a person is near a potential fall hazard, prompting them to stop and exercise caution.

- Navigation: These indicators also aid in navigation, helping visually impaired individuals orient themselves in a public space. Following a line of TWSIs allows people to navigate complex environments like transit stations or public squares more confidently.

- Independence: TWSIs significantly contribute to the independence of visually impaired individuals. By providing reliable and consistent cues, these indicators allow people to move about public spaces without assistance, fostering greater autonomy and confidence.

Types of Tactile Warning Surface Indicators

Two primary types of TWSIs exist - detectable warning surfaces and directional surfaces.

1. Detectable Warning Surfaces: These are typically used to alert individuals to hazardous areas. They are characterized by a pattern of truncated domes and are often found at the edge of sidewalks, at pedestrian crossings, and on transit platform edges. The unique texture and layout of the domes provide a clear and unambiguous warning that prompts caution.
2. Directional Surfaces: These indicators guide individuals along a specific path. They have a linear pattern of raised bars, which can be felt underfoot or detected with a cane. Directional surfaces are often used in large open spaces, such as plazas or parks, where traditional wayfinding methods might be insufficient.

Standards and Regulations

Implementing TWSIs is governed by various standards and regulations to ensure consistency and effectiveness. In the United States, the Americans with Disabilities Act (ADA) sets out specific requirements for TWSIs, including their size, spacing, and placement. Similarly, other countries have their own guidelines, such as the UK's Department for Transport's guidelines and Australia's Disability Discrimination Act (DDA).

- ADA Compliance: Under the ADA, TWSIs must be installed at curb ramps, transit platform edges, and hazardous vehicular areas. The guidelines specify the domes' dimensions, the distance between them, and the contrast in color to ensure they are easily detectable.

- International Standards: Different countries have adopted standards that align with their specific needs and infrastructure. For instance, Japan has extensive tactile paving systems known as Tenji blocks, common in urban areas and transit stations.

Learn more about how StrongGo’s TekWay® meets ADA compliance.

Tactile Warning Surface Indicators (TWSIs) are vital in creating inclusive and safe public spaces. TWSIs enhance safety, facilitate navigation, and promote independence by providing essential cues to visually impaired individuals. 

At StrongGo, we believe in developing a more accessible environment to ensure equal opportunities for people with little or no vision and the disabled community. We do this by engineering and designing effective, detectable warning dome tiles. Learn more by emailing csd@stronggo.com or exploring the rest of our website.