Tactile paving
Tactile paving is a system of textured ground surface indicators found at roadsides, by and on stairs, and on railway station platforms, to assist pedestrians who are visually impaired.
Tactile warnings provide a very distinctive surface pattern of truncated domes, cones or bars, detectable by a long cane or underfoot, which are used to alert the vision-impaired of approaching streets and hazardous surface or grade changes. There is disagreement between the design and user community as to whether installing the aid inside buildings may cause a tripping hazard.
A system of tactile paving was first instituted in Japan at pedestrian crossings and other hazardous road situations; the United Kingdom, Australia and the United States picked up the standard in the early 1990s. Canada started incorporating them into transportation first in the 1990s, and then added them to other aspects of the built environment in the early 2000s.
History
paving was first developed in 1965 by Seiichi Miyake, who was inspired by braille. The paving was first introduced in a street in Okayama, Japan, in 1967. Its use gradually spread throughout Japan and then around the world. Tactile paving is widely used in subway stations and sidewalks.Today, yellow tactile paving is ubiquitous in Japan. For aesthetic reasons, for example in front of hotels, the colour of the paving might be non-standard, to match the colour of the pavement or stone floor. Sometimes the paving contours are produced with steel stripes and dots.
Tactile tiles spread rapidly after their adoption by Japan National Railways. In 1985, the system was formally named "Hazard Guide for the Vision Impaired". Its modern form can be classified into two types: one has small, round bumps upon the surface of the block, which are felt through a sole, and the second is a directional aid, with long, slender bumps being installed on the surface.
However, many types have been manufactured and installed as an experiment. This has resulted in a situation which may be confusing for both the vision-impaired and the elderly. Usually the color of a tile is used to check the proper direction. If the color is not the usual one, there may be confusion. That has led to the standardisation of the system throughout Japan.
Now, the use of tactile tiles is spreading throughout the world. Many tactile tiles have been installed at subway stations and on sidewalks in Seoul, Korea. The installation in Seoul is more challenging than in Japan, because the surface of various sidewalks in Seoul is not flat, so there are many places where the meaning of a tactile tile is not clearly conveyed.
Tactile tiles were adopted at each facility used for the Sydney Olympic Games in 2000, and are ubiquitous in Australian public transport facilities. That trend has also been apparent in the UK, the US, and throughout the world.
Tactile patterns
Warning block tactiles
Blistering tactile
These are used for pedestrian crossings. The purpose of the blister surface is to provide a warning to vision-impaired people who would otherwise, in the absence of a change of height of >25 mm, find it difficult to differentiate between where the footway ends and the carriageway begins. The surface is therefore an essential safety feature for this group of road users at pedestrian crossing points where the footway is flush to the carriageway, to enable wheelchair users to cross unimpeded. The profile of the blister tactile surface consists of rows of flat-topped blisters in a square pattern.This style is also known as "truncated dome" or "detectable warning surface".
Offset blister tactile
The offset blister tactile is also known as the "platform edge warning surface". The purpose of this surface is to warn vision-impaired people of the edge of all off-street railway platforms. According to UK standards, the offset blister tactile surface consists of flat-topped domes, spaced 66.5 mm from the center of one dome to the next one.Tactile paving units can be manufactured in any suitable paving material and may be any color that provides a good contrast with the surrounding area, to assist partially sighted people. The current guidance recommends that the off-set blister tactile surface be used for all off-street rail platforms including:
- Railway platforms
- Off-street light rail transit platforms
- Rapid transit platforms
Lozenge tactile
The lozenge tactile is also known as the platform edge warning surface. The purpose of the platform edge warning surface is to warn vision-impaired people that they are approaching the edge of an on-street light rapid transit platform. UK standards say the profile of the lozenge tactile warning surface comprises rows of 6±0.5 mm high lozenge shapes, which have rounded edges so as not to cause a trip hazard. The tactile paving units can be manufactured in any suitable paving material. The surface is usually buff colored, but can be any color, other than red, that provides a good contrast with the surrounding area, to assist partially sighted people.The lozenge tactile paving units should be installed to a depth of 400 mm parallel to the platform edge and set back a minimum of 500 mm from the edge. They should never be installed closer to the edge than that, because pedestrians may not have sufficient time to stop walking once they have detected the tactile warning surface.
Directional block tactiles
Standard directional or guidance tactile
This type is also known as "tactile direction indicator", and is standardized in the UK but not the United States as a whole.The purpose of the guidance path surface is to guide vision-impaired people along a route when the traditional cues, such as a property line or kerb edge, are not available. It can also be used to guide people around obstacles, for example street furniture in a pedestrianized area. The surface has been designed so that people can be guided along the route either by walking on the tactile surface or by maintaining contact with a long white cane.
The guidance tactile comprises a series of raised, flat-topped bars running in the direction of pedestrian travel. The bars are 5.5±0.5 mm high, 35 mm wide, and spaced 45 mm apart. It is recommended that the guidance path tactile be in a contrasting color to the surrounding area, to assist partially sighted people. The guidance surface is recommended for use in the following circumstances:
- Where the traditional guidance given by a standard footway between the property line and carriageway does not exist
- Where pedestrians need to be guided around obstacles
- Where a number of visually impaired people need to find a specific location and in transport terminals to guide people between facilities.
Corduroy hazard warning tactile
UK standards specify that the profile of the corduroy tactile surface comprises rounded bars running transversely across the direction of pedestrian travel. The bars are 6±0.5 mm high, 20 mm wide, and spaced 50 mm from the centre of one bar to the centre of the next. The tactile paving units can be manufactured in any suitable paving material. The surface is usually buff coloured, but can be any colour, other than red, that provides a good contrast with the surrounding area to assist partially sighted people.
The corduroy tactile can be used for any situation where vision-impaired individuals need to be warned of a hazard, such as:
- the top or bottom of stairs
- the foot of a ramp
- a level crossing
- where people may unintentionally walk directly on to the platform at a railway station
- where a footway joins a shared route
Cycle way entrance tactile
According to UK standards, the cycle way tactile comprises a series of continuous raised, flat-topped bars, each 5±0.5 mm high, 30 mm wide and spaced 70 mm apart. The central delineator strip should be 12–20 mm high, 150 mm wide, with sloping sides and a flat top of 50 mm. The delineator strip should be made of a white material.
The tactile surface should be used on any segregated shared route where the pedestrian side is not physically separated from the cyclist side. The tactile surface should be laid at the beginning and end of the shared segregated route, at regular intervals along its length, and at any junctions with other pedestrians or cyclist routes.
This pattern serves as "cyclist warning rumblers" so that bicycle riders who are distracted are alerted of an upcoming pedestrian or vehicle hazard by vibration through the handlebars, seat, and pedals.
Trapezoidal cycle path separator
A long, continuous trapezoid shape, also known as a "tactile warning delineator", can be used to create separate sidewalk lanes for pedestrians vs. bicycles.Role of color and contrast
The United Kingdom Department for Transport guidance on the installation and use of tactile paving places a heavy emphasis on the role of contrast. The guidance repeatedly states that tactile paving should be chosen to provide strong color contrast with the surrounding paving material, because studies have shown that this aids partially sighted individuals. Most tactile paving is available in a range of colors and materials making good color contrast easy to achieve with appropriate choice of tactile paving.There are only two cases where the color of a tactile has a specific meaning:
- Red is reserved for use with blister tactile to denote a controlled pedestrian crossing
- Buff blister tactile are reserved for use at uncontrolled pedestrian crossings