Proceedings of: Workshop on Improving Building Design for Persons with Low Vision

Other Contrast Attributes

Comment and Question by Jim Woods: [This] picks up on what Fred was saying, but I heard something that is just blowing my mind. It’s confusing me and I want to get some understanding. Several of you used “contrast” in ways that I’m not used to considering contrast – contrast of texture, contrast of some of the other attributes. But do you see contrast in a different way than “light and dim”?

And that’s a big issue, I think, as far as us trying to get into a common vocabulary. I’d just like to hear you express, for example, when you talk about texture contrast, how do you [measure and] perceive that differently than you do color contrast?

Responses by [three Participants]: Change. It’s a change in light. It’s an obvious change.

Response by [fourth Participant]: For example, in our doorways in our center, we use wood-carpet-wood, and it’s a whiter color. And we have carpet and it’s all butted-up so there’s no step down or anything. But it’s a change in texture so a person who’s visually impaired or blind, they would know – they’ve got the texture – but they’ve got both [cues].

Response by [fifth Participant]: There’s a change in resiliency between carpet and wood, and that change in resiliency is a good cue because it’s also, often, an auditory cue if you’re using a cane or it’s an underfoot cue if you’re not using a cane.

Question by Jim Woods: Okay, but if we were to go color-neutral, [what are some of the other aspect of contrast?

Response by [Participant]: You’re going to feel the difference between the smooth surface and a soft surface or a textured surface. You feel that because it’s a difference in the friction, basically.

Response by [Participant]: When we did our [consensus review], we had huge discussions going on for hours because the lighting designer would use [“contrast”] one way and the interior designer would use it another way. And I mean, I had a lot of terms, and we could pull out some of those terms.

Question by [Participant]: So, how would you measure contrast in a non-visual way?

Response by [Participant]: We say obvious change.

Comment by Vijay Gupta: [This] is that experience from that obvious place I had. So I complained to the director of the office that very problem and a few days later, in that lobby, I saw some black leather chairs I say, they listened to me. Later, I came back – the chairs were gone. So I asked – I went back to the director and I said, what happened? Oh, Jesus, somebody made a mistake and delivered the wrong chairs.

Question by [Participant]: [What about surface changes?] – the old bumps, you know, in the road that they have. That seems to be the thing that you do, too, for low-vision people or blind people, because they stand up. But they’re really hard for older people with low vision because they’re hard to walk on. Your walkers get stuck in them and things like that.

Response by Marsha Mazz: Actually, we’ve researched that, and I know people say that, but the research doesn’t support that claim. So I will tell you that there is a constituency of people who have fought that requirement forever and they are the successors to the constituency of people who fought installing curb ramps on the basis that their belief that curb ramps would be dangerous to blind people.

And now they’re saying that you can’t put warnings on curb ramps or you’re dangerous to walking people. If you walk, you don’t have to use the curb ramp. In fact, most older people, including older people who use walkers, prefer not to use a sloped surface, not because of a detectable warning, but because it’s easier to step down off a six-inch curb than it is to lift your feet and walk down a slope. And this is why we had such competition over the issue.

Comment by [Participant]: [Maintaining] balance --

Response by Marsha Mazz: Right – exactly right because your walker is not on a slope. We have a constituency of people who like stairs and don’t like ramps for disabilityrelated reasons. But [others have] been using these detectable warnings on interior locations and to aid in wayfinding. We’ve participated in international forums on this subject. In some foreign countries, they do use a variety of detectable warnings – or [as] they call them in Japan: “taki blocks” – to aid in wayfinding.

And some of them are herringbone patterns and all kinds of other patterns, most of which people who have vision impairments can’t really distinguish one pattern from the other. They just know that they’re on a pattern. And so we find that the research, again, doesn’t support their use for wayfinding, most importantly because detectable warnings have a single purpose.

Like a stop sign, the detectable warning signifies to an individual who is blind or has low vision, stop here; don’t proceed further because you’re about to enter a vehicular area. So if we start proliferating these things all over the environment and putting them at drinking fountains and putting them here and putting them there, they lose their utility as a warning. They will no longer serve as a warning. We selected that pattern and that particular design because it was not readily available in the environment. Corduroy actually tested better for detectability but didn’t serve as a warning.