The Sound Masking Blog
5Apr/12

Speech Privacy in Open Plans

Speech Privacy In Open PlansThis week, I read several articles on the acoustical design of office spaces and noticed a trend that provides compelling fodder for today’s blog. This trend – and, at first, it’s going to sound odd coming from me – is to overemphasize speech privacy in open plans.

Am I suggesting that speech privacy isn’t needed in this kind of environment? Of course not. Some degree is not only necessary, but beneficial. After all, people are talking about work-related (and sometimes personal) matters, both in person and on the telephone. In some situations, the law even mandates that reasonable steps be taken to safeguard an individual’s right to it – for example, the HIPAA regulation in the United States, which applies to personally identifiable healthcare information.

Speaking from an open plan perspective, the questions are: how much speech privacy is needed, under what conditions and at what distance? The answers can significantly impact decisions regarding overall acoustical design. In many cases, project teams believe that meaningful levels aren’t needed in this type of environment. Everyone’s sitting out in the open anyway, right? The topic is dismissed as unrealistic or unnecessary.

Unfortunately, this is a significant miscalculation of the importance of speech intelligibility – one that can mostly be attributed to the narrow focus on privacy.

What other benefit does lowering speech intelligibility have?

Well, understandable speech is the single greatest source of disruption in open plans. Yes, simply hearing someone speaking can disturb your concentration. But this problem is greatly magnified when you can clearly understand what they’re saying. In other words, if you can follow a conversation, it’s much harder to ignore it, which can impact your productivity, error rates, comfort level and overall workplace satisfaction.

The ironic part is that the steps you need to take in order to reduce the intelligibility of speech are the same ones you need to take in order to provide privacy. The only difference is how you see the benefit: from the perspective of the group listening rather than the person talking.

While it might be easy to dismiss the importance of speech privacy in an open plan, it’s pretty hard to justify increasing disruptions. But by focusing on privacy alone, poor design choices are made that do just that, negatively impacting concentration, not to mention background sound levels, dynamic range and reverberation times.

In the end, we’ll all be better off if we change the words we use to describe the acoustical needs of open spaces. Rather than emphasizing speech privacy (again, not to suggest that it isn’t needed or possible), we should identify the need in terms of lowering noise. Or, better yet, let’s just talk about lowering speech intelligibility in open plans, which would deliver both improved speech privacy and a reduction in noise disruptions.

You may be more motivated by the need for privacy or by the need for a high performance workplace. Do the things necessary to lower speech intelligibility in the open plan and you’ll reap the rewards of both. What a deal!

Cheers,

Niklas

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    • http://www.archoustics-mountain.com/Home.html Jim Berneike

      Well written articles Niklas! My colleague Win Murray just pointed out this blog to me, otherwise I would have been writing this a few months ago.

      Thanks for writing these articles, they’re really quite helpful for understanding and preparing for some of the nuanced problems or objections that people may have with regards to sound masking.

      I have an idea for a post, or even a visual analogy that could be used in a PP presentation, with regards to dynamic range and the information carried in the sound energy.

      I enjoy photography, and especially the potential for digital manipulation. With regards to camera equipment, manufacturers of course want to increase the sensitivity, or dynamic range, and the amount of information that can be captured in an image. The same should be true in the music recording industry (sadly though it’s often not the priority), giving us a more dynamic and live sounding musical performance, with every nuance that we’re capable of hearing.

      We of course want just the opposite in a work environment so that our attention is not drawn away from the work that we’re doing.

      As a visual analogy of dynamic range I’d have two images next to one another – on the left an image with high dynamic range, on the right the same image with the dynamic range flattened – the image is still there, but much of the information has been taken out. With sound masking, the sound is still there, but much of the information has been taken out of it, and the information is what distracts us or reduces our privacy.