
People with balance and mobility difficulties are obviously a group at higher risk of sustaining injuries as a result of a fall. In Australia, a staggering 144,000 hospital day beds annually are attributed to admissions due to falls. Many of these falls can occur due to operational issues such as food stuffs being dropped within a food and beverage area, however a great many can also be attributed to the design of the built environment.
Glare / Reflectivity
Highly reflective floor finishes can be a significant source of glare; all the more troubling given the extensive surface area floor finishes, by nature, are applied to. Significant sources of glare can be extremely disorienting for many people, not just people with low vision, as the ability to locate important landmarks for orientation can be affected. Of greater concern however, is the possibility of sources of potential hazard (e.g. an unnoticed step, piece of furniture, or change in gradient) going undetected due to the presence of glare.
Wayfinding and Orientation
Selecting floor finishes which contrast with abutting finishes at walls and furnishings, assists in defining a space more effectively and clearly establishing pathways and movement through a building. This of course reduces the risk of trips, falls and collisions; and provides natural and intuitive cues for where movement should occur in order to locate key areas within the building.
When selecting contrasting finishes, luminance contrast is what is considered to be most perceivable to people with low vision. Luminance contrast is described as a comparison of light being reflected by two surfaces; not necessarily just colour. A luminance contrast of no less than 30% is what is considered to be appropriate for most people with low vision. For information on how this can be tested, appendices are included within AS 1428 Parts 1 and 4.
Patterned Designs and Flooring Layout
Flooring designs that include bold elements set together can be confusing to a person with low vision. These include contrasting tiles set together within a location, a bold pattern on a carpet weave, or mosaics with large bold elements. These can often be mistaken for a change in level or even a physical item placed on the floor.
Tolerances and Transitions in Flooring
Very small changes in level can be detrimental to people with mobility difficulties who are ambulant as well as those who use any type of wheeled mobility aid. Transitions of only a few millimeters can become the source of a fall, or a barrier which prevents a person from accessing areas within buildings which must be made available to all members of the public. AS 1428 Part 1 advises of changes in level of up to 3mm (5mm where individual tiles / surfaces a beveled or rounded). Carpet pile heights should be less than 6mm and recessed where applicable.
Slip Resistance
Recent changes to the Building Code of Australia (BCA 2014) now see a requirement for slip resistance at stairs and ramps. Step ramps, that is, pedestrian ramps with a gradient of 1:10 will require a higher level of slip resistance to longer 1:14 ramps. Designers and specifiers are also allowed flexibility with designing floor finishes on stair treads by either providing a suitably slip resistant surface to the entire tread or to just the nosing of each tread as well as the landing edge. The specific slip resistant values necessary are include in the BCA and the method of assessment is outlined in the Australian Standard AS 4586: 2013 Slip resistance classification of new pedestrian surface materials.
Even though the BCA does not require other pedestrian surfaces to meet a particular level of slip resistance designers are best advised to consider HB 197: 1999 - An introductory guide to the slip resistance of pedestrian surface materials in their selection of floor finishes.
Other Building Elements
Stairs are an area where falls often occur and, of course, where the resulting injury can be particularly serious in nature. Highlighting stairs at the nosing of the goings is an effective strategy which can assist in preventing unnecessary falls. A solid continuous band (50-75mm in depth) with a high level of slip resistance and luminance contrast should always be provided in these instances.
Tactile ground surface indicators are now a BCA requirement in public areas where potential hazards occur (i.e. stairs, ramps, road crossings), and of course provide a vital cue to people with vision impairment in locating these hazards. These must also provide a luminance contrast of no less than 30% - it is recommended that these are tested as a matter of fact in each application and subjective judgments of colour are not made as this can be both misleading and inaccurate.
George Xinos
Functional Access Solutions