A collection of articles discussing the importance of providing a luminance contrast between surfaces of building elements, as well as considering this concept in wayfinding.
Seeing the Light with Luminance Contrast
When we consider the need for contrasting surfaces in the built environment, there are some important terms we must understand from the outset. International Standard ISO 21542 defines ‘luminance’ as the intensity of light emitted or reflected in a given direction from the surface element divided by the area of the element in the same direction. This value is expressed as a Luminance Reflectance Value, or LRV.
ISO 21542 defines this LRV as the proportion of visible light reflected by a surface at all wavelengths and directions when illuminated by a light source. The LRV is expressed on a scale of 0 to 100, with a value of 0 points for pure black and a value of 100 points for pure white. Many reputable suppliers and manufacturers will provide the LRV of their products, including paint companies.
When we test the suitability of one surface against that of another we actually need to check that the luminance contrast (or visual contrast) is acceptable to aid in visual identification. Australian Standard (AS) 1428.1 defines luminance contrast as the light reflected from one surface or component, compared to the light reflected from another surface or component.
Typical surfaces to be tested for luminance contrast are floors, walls, doorways, key fixtures and fittings, signage, stair components and the like. In Australia, we have prescriptive requirements that require minimum levels of luminance contrast (LC) in the built environment.
Read the full article here – https://sourceable.net/seeing-the-light-with-luminance-contrast/
Richard Branson and Inclusive Design
How many times have you seen people cautiously approaching a glazed entry to a shopping centre without knowing where the automatic doors are? Now imagine you have some level of vision loss as you’re approaching that same entrance. Will you register the location of the glazed entry? Will you identify the doorway? Can you safely move through the doorway?
Earlier this month it was reported in the press that Sir Richard Branson had been “in the wars.” What he’d actually done was visit a local jewellery shop to look for a gift for his wife only to walk into the entry door. Branson was quoted as saying “I strolled purposefully into the shop, not noticing there was a glass door in my way. Crash! I hit the glass head first and I got this painful cut above my left eye.”
Branson’s unfortunate accident resulted in three stitches over his eye and highlights that the visual cues most of us register as we approach a doorway may not be so evident to everyone at all times.
These reasons could obviously be due to a person’s low vision. After all, Vision Australia reported that in 2013 there were 357,000 people in Australia who were blind or had low vision. They also predict that this number will grow to 564,000 by 2030, in part no doubt to an ageing population. From a global perspective, in 2010 the number of people who were reports as being vision impaired was estimated at 285 million, of whom 39 million were blind. However, the reasons why people don’t register key features in a building could also be due to distractions in the area, visual confusion, glare on surfaces or poor lighting (or maybe in Branson’s case, evading the paparazzi).
Now consider people moving around a built environment for a moment and think about which other features and facilities would benefit from increasing their visual contrast, thereby increasing a person’s ability to identify these features.
Read the full article here – https://sourceable.net/seeing-the-light-with-luminance-contrast/
Wayfinding: Pointing the Way Out
Good wayfinding allows a person who is blind or has low vision to “benefit from a well-designed environment that presents a predictable set of physical circumstances,” but it can also benefit all occupants of a building, including those with mobility or activity limitations.
When we consider wayfinding, we generally think about people entering a building and moving to key features and facilities without putting too much thought to how they would find their way out during an emergency.
There are a number of key wayfinding principles to take into account, and notably, the paths should be simple in design and non-confusing for occupants, particularly for those who may experience stress or those with reduced mental or cognitive abilities.
Additional to these accepted principles, exit doorways can also be provided in a contrasting colour scheme which not only achieves a contrast in the colours around the doorway, but also a contrast in the luminance reflective values of abutting surfaces (or the way light behaves off each surface). This will help exit doors to stand out from their background and will assist those people with low vision, who may miss other visual cues such as an exit sign over the doorway, to identify an exit door. This approach has also been known to assist those occupants with a cognitive impairment.
Read the full article here – https://sourceable.net/wayfinding-pointing-the-way-out/