Wednesday, April 22, 2009

Stair Safety - It's All About Contrast Ratios

As our population ages and gets poorer eyesight, the ability to see subtle changes in surfaces before us, particularly in dim light, is diminished. This is a good example of stairs that have no clear transition point. Recommended solution: Install a contrasting color tape or paint strip along the edge of the steps. There are many 'stair tread' or 'grit tape' products out there that are designed for direct application to floors. Just remember to strip the floor of wax and dirt before you do it, otherwise you'll just be creating another hazard in place of the one you just resolved. There are also grit tape strips and paint that have photoluminescent glow-in-the-dark strips in them, which can help in the event of a power outage.

Where this situation occurs on carpeted steps, there are two possible solutions:
  • Recarpet the stairs with a two-tone carpet scheme so there is a contrasting color strip for about 2" along the step nose, or
  • Add a grit covered metal or fiberglass strip that is screwed-down over the carpet and crushes down the carpet so that the top of the strip is even with the remainder of the carpet so there is not a trip hazard.
A solution I have seen that is NOT recommended is laying down a strip of white gaffer's tape. Although well-intentioned, it can work loose and create a trip hazard.

The strip color should contrast the carpet color in low light. Our vision tends to loose the color component in low light conditions, so an easy way to test this is to view the proposed color combination with a black and white video camera or still camera that is slightly out-of focus. If all you have is a color camera, then take the picture and pull the color saturation out of it with a photo editor. What may appear to be a good color combination to youthful eyes in full light, may indeed not be a good solution when viewed as an elderly color-blind person.

Another issue at this location is that the railing does not meet the 4" sphere rule to prevent children from falling through the railing bars.

From an audience focus perspective, the railings in front of the seating should be a dark matte finish so as to not distract from the focus of the game (this is more important in live theatre and cinemas). The railing at the end of the flight of stairs should contrast the background (in this case, the basketball court), so that it's distance is not misjudged.

Other listing of interest:

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