Dr . Erica Walker is a public health researcher and the founder of Noise and the City and the Community Noise Lab. She's been tracking the impact of noise on communities in Boston as well as in other cities. In this interview, she talks about how she was personally affected by noise and how it inspired her to help others. She stresses the importance of quantifying how noise makes people feel and how it increases their stress levels, not just tracking decibel readings.
Dr . Erica Walker is a public health researcher and the founder of Noise and the City and the Community Noise Lab. She's been tracking the impact of noise on communities in Boston as well as in other cities. In this interview, she talks about how she was personally affected by noise and how it inspired her to help others. She stresses the importance of quantifying how noise makes people feel and how it increases their stress levels, not just tracking decibel readings.
Cary: In this episode of Soundproofist, I have a conversation with Dr. Erica Walker, a researcher in environmental health. Erica went all over Boston to measure sound levels in the city, and she interviewed residents about their perceptions of noise. She goes beyond the decibel to looking at the psychological and physical impacts of noise on a community.
Cary: Her work with the help of some volunteers launched the website, ‘Noise in the city’, where you can listen to interviews and sound samples, look at maps that show noise levels, participate in a survey, and review data from her research.
Cary: Erica also released a free app called ‘NoiseScore‘. You can use this app to measure in decibels the environmental noise levels, but you can also use it to track your perception of the noise. You’ll learn in this conversation that perception makes all the difference in how it impacts human health, but it’s much more difficult to measure.
Cary: NoiseScore is available at no charge for both iPhone, and Android.
Cary: We talked over Skype and we talked about her research, and her interest in going beyond Boston to help other communities. Her first step is to create better tools to help people measure the problems they face. So, let’s take a listen.
Cary: I've read a couple of interviews with you that were linked to your website, and I kind of know the story from reading that of how you got involved in dealing with noise. Just briefly, can you just describe what prompted you to do that?
Erica Walker: Yes. So you know, it was a personal experience. I was a working artist, and I worked in my apartment. My apartment was my studio, my office space, and the people who lived above me had two small kids. And when they moved in, it just completely changed the soundscape of my apartment. So, their floor was my ceiling. And so the kids would run back and forth all night long, all day, all night. It just drove me insane. I complained to my landlord. They were very nice about it, they said ‘document the times that it happened, and anything that you could think as being important, and we can build a case against them.’
Erica Walker: And so, I did that, and in the process of trying to document evidence about how loud they were, I wanted to see if other people were suffering from the same thing, and what they did to alleviate the problem. And so by doing that, I found out that there was this entire community of people who live in these shared spaces who were given the noise issues from their neighbors. I was just like — okay, this is way bigger than me, so I could either deal with my issue, and that satisfies me. But what about the other people? I’ve got to take one for the team.
Erica Walker: So I ended up moving out. And I just decided to kind of really get down into how widespread this problem is, and how’s it impacting our health.
Cary: Then it is really hard when you can’t control … I think that is, as you said, you can’t control what’s happening. It’s like the only ones who are in control are the people making the noise, and there may not be anything you can do about that.
Erica Walker: Exactly. And I think that noise issues are a proxy for control. I think you hit the nail on the head. If you don’t feel like you have control over your life, everything else is out of whack.
Cary: And I think that’s what people are looking for — it’s like, what can I do about this?
Erica Walker: Exactly.
Cary: And in the past … well, what do people do? They maybe call the police, the police are busy with other issues. If you have a set up where you’ve called the police on someone who is really making an outrageous amount of noise, there are times when that person, or people, they may not want to change. Or they’re incensed because you tried to do something about it, and they do it again.
Erica Walker: They retaliate.
Cary: I also think there are just issues with the way that American homes are built. Apartments. And I’ve talked to people before who said, no one really thinks about the acoustics of a place when the developers are building a building. It might be an afterthought. And then it’s a little bit hard to deal with. So, some of the things that I know affect a lot of people here is simply that. It’s that you have a half inch of drywall on one side of some two-by- fours, and a half inch of drywall on the other side. And of course you’re going to hear stuff. I’m wondering when you started getting into studying acoustics, is that what you basically went into at that point?
Erica Walker: Yes. So I studied community noise and its impacts on our health. I did my PhD in public health, so I did environmental health and epidemiology. But my research focus was on community noise.
Cary: Well, I did see in one of the interviews that you were diving into learning all about decibel levels and things. You mentioned something about an ‘A-weighted decibel’, and I have to admit, I don’t know what that is either. So, what does that mean to a layperson?
Erica Walker: Right. So it’s kind of like how we … it’s not kind of like, it is how we regulate and describe noise throughout our environment. So, let’s say for example, your neighbors are being loud, and you call the police, and the police come with their sound level meter, if they actually do that. They may not do that. They measure the noise, and they report, “Hey, it’s not that loud.” Quote, unquote. It’s this decibel. So the decibels that they are using is the A-weighted decibel and the A-weighted decibel is a weighting system that makes the assumption that the noise that we hear is the noise that’s relevant. They’re saying that noise that we hear is the noise that we process through our auditory system, right? We hear noises, but we also can feel noise.
Erica Walker: So, if you look at a noisy event, let’s say you’re measuring that loud party, or that loud neighbor. You can break down that noise profile along an octave band and the octave band has these bands that range a little from over zero hertz to about 20,000 hertz. So the lower the hertz, the more the sound can be characterized as a rumbling or a vibration and as you move up the hertz, it becomes more of a hissing, kind of a whistle cricket-type noise.
Erica Walker: That octave band is described in the character of the noise, so when we report or regulate the A-weighted sound. We chop off the contributions from the low frequency and we chop off the contributions from the high frequency because we don’t normally process those through the auditory system. Or the auditory system is less sensitive to the sound that’s in those hertz or frequency bands. If you are in an apartment and the neighbor is moving furniture above you, if you’re using an A-weighted decibel it's cutting off the contributions from that rumbling aspect of the noise. And the rumbling aspect of the noise is what’s bothering you, right? And the police come and they measure it, they’re using a metric that chops off the issue, so it’s I actually like I know it’s the low-frequency sound that’s really bothering me.
Cary: If for example you were trying to make a recording to make a case to your landlord or something and say "here’s what I hear in my apartment" -- it probably also wouldn’t pick up those super low frequencies right? It would maybe pick up if people were yelling, for example.
Erica Walker: Right, it would just truncate it. Exactly. It would truncate the sounds that our auditory system is not sensitive to. We process noise outside of the auditory system. If you’re in that apartment with the neighbors or something above you, and you put in earplugs, you may not be able to hear it so much. But you will definitely feel it. So for me I’m really interested in the types of noise that we feel because it’s not regulated, and it’s not really studied as much. But it’s very pervasive in our environment, and it’s really, really, really hard to deal with because it can penetrate through walls, it can travel long distances. So it’s just a really quote, unquote ‘sinister side of noise exposure.’
Cary: Yeah, I think so. And I also think, again with the way that we have construction here. I think that the wood-framed houses and apartment buildings, the wood is resonant and is actually a conductor isn’t it? For noise?
Erica Walker: Yes.
Cary: If you have the framing of a building, of an apartment building and someone in one apartment is doing something like banging on the floor, you’re going to hear it on a different floor. And maybe not even on an adjacent wall — because it’s traveling through the joists and it’s traveling through the studs, and it’s like a whole network. And probably by the time it reaches you in your apartment, it’s picked up all those low frequencies.
Erica Walker: And it’s been amplified.
Cary: And it’s been amplified. Yes.
Erica Walker: Exactly. It’s funny, when I had a reasonably friendly relationship with my neighbors upstairs, one time he was like ‘can you come upstairs we’re not really doing anything’ and to a degree he was right. The kids were running across the floor, but it was like a two-year-old kid. Then you’re like "then why does it sound like a herd of elephants?"
Cary: Right.
Erica Walker: It’s because you said it’s because of poor construction materials that amplify sound as opposed to absorb it. Yeah, you’re absolutely right.
Cary: That is something that is very hard to change. It’s the same issue I have with restaurant noise — although a little different because the restaurant noise you can do something with sound absorption in that room. When you’re in an apartment building you can put up all the sound absorption you want. But it’s not going to do anything for stopping that neighbor noise from coming in.
Cary: Maybe it’s a nice thing to do for your neighbors, because maybe you’ll dampen some of the sound you’re making inside your place. But it’s not really gonna help.
Cary: You did some field research as part of a project, ‘Noise in the City’, which I think was mostly focused in Boston right?
Erica Walker: Yes, greater Boston. Yes.
Cary: During that time you went around the city and measured noise and interviewed people, is that right?
Erica Walker: Yes. Exactly. So, from my dissertation, the dissertation part of my research was actually going in about the city and measuring noise levels in different locations. However the more subjective perception piece was for Noise in the City. When I was out measuring noise, people would come up to me — I’m some crazy black woman with a microphone standing in their neighborhood at odd times of the day — and they were like, “What are you doing?” and I would then tell them I’m measuring sound and they would be like, “Are you from the city? I’ve been calling for like the past…” and I would be like, “No, no, no, I’m a researcher.”
Erica Walker: Through that process people started talking to me about not only the sound levels but their perception and how it was impacting their health. And so if the perception piece which is Noise in the City kind of dealt with the community noise perception outside of the actual noise levels.
Cary: Yeah, I think that’s key really, that’s it — perception. And you can’t put a measurement really on perception because it’s subjective. I think you probably also run the risk of being seen as overly sensitive… and don’t take them seriously. You do need some sort of a measurement to be objective I think. But if those measuring tools don’t capture the right data, they don’t make your point, because any kind of noise mitigation comes with a price. And to be persuasive, it probably takes a number of factors, and I suspect that’s what your goal is, to compile all this into data that is actionable.
Erica Walker: Yes, and data that is representative of the entire noise experience. So if we’re already starting with the metric that cuts off things that are very important and very pervasive in our environment and we’re not even considering the perception component, we are only telling a fraction of the story. And for me, I’m interested in the relationship between community noise and health. I wanna make sure that how we are describing community noise when we look at the relationship is correct.
Cary: I agree. I think another part of being psychologically affected by noise, which, for example you can’t sleep very well. If you have sirens going off or neighbors partying or something like that. Another component may be the stress it has on you of not being able to do anything about it, that component also must be an impact on your health. When maybe you can’t get to sleep because you hear the kids stomping at three in the morning and you knew something would happen but you didn’t know when.
Erica Walker: Exactly, I’ll share this with you. I sent an email, but from the survey report that we released a couple of years ago, there’s a part where we asked people in the greater Boston area, what is it about noise that you just find so annoying? And if you look at the responses and the high rates of agreement, they were saying things like, “I feel like if I complain nothing will be done," “I can’t control it, it’s impacting my health.” I’m looking at this data and thinking …this sounds like someone explaining a sexual assault. But we’re just talking about noise.
Erica Walker: People feel completely held hostage by sound in their community and on top of it they feel like they can’t do anything about it and it’s impacting their health. For me that was just like an ‘aha’ moment, like, "oh I get this, this is deep."
Cary: And we can all relate to it really I think. If we didn’t have ways of sharing this information with each other you could just feel like, it’s just me dealing with this issue, but everyone else I know doesn’t have it. If you scratch the surface I’m sure you’ll find that almost everyone’s having some kind of an experience. Even if they have a house that’s free-standing it could be the neighbor’s subwoofer’s coming through a shared wall somehow.
Erica Walker: Exactly, I’m dealing with an issue with a guy who used to live in Boston and he moved out into the suburbs because he is really just over it. He lived in an area that was directly under a flight path and he was like “I can’t take it anymore,” so he moved to a small town and he has another issue, his neighbor’s dogs — they bark 24 hours a day.
Cary: Oh my God.
Erica Walker: He was like, “I didn’t leave flight path sound to move out to the middle of nowhere and then be bothered by these neighbor’s dogs.” It’s ridiculous.
Cary: I approached it at first was like what products can I buy and what processes can I do to make my apartment more like a fortress. You can only do so much, especially if you’re a renter. In fact you may not be able to do much at all. The second thing might be, well, what can I do to persuade my neighbors to… maybe that’s your first step. What can I do to persuade or negotiate with my neighbors over this? And then the third thing might be like what you ended up doing, was just like, I give up or this other person you talked to, I’m gonna move, but you don’t know that the next place you move to is not gonna have some of those same issues.
Erica Walker: Exactly.
Cary: It seems like some of your field work, when you would go out and interview people, you could hear all these jackhammers and things in the background, so that’s a whole other kind of noise also. It’s not illegal to repair a street... or build a building down the street or something like that. But those are some of even the most intrusive noises because they’re so loud. They’re automatically at the high end of the Richter scale...the high end of the decibel scale...feels like Richter scale right?
Erica Walker: It does.
Cary: Are you involved at all in any kind of neighborhood local issues for parameters around construction hours or conditions or anything like that to make it more bearable for people who live in the vicinity of these noisy projects?
Erica Walker: No, not yet.
Cary: Okay.
Erica Walker: Because I feel like we haven’t developed or used the right metrics to even get people at the table, if we’re talking about a jackhammer which has high components of low frequency and high frequency noise, the way that we traditionally measure it and regulate is still used in the A-weighted decibel. So we need to go back and convince people that we need to use completely different metrics to describe this. And only then can we get to the table to talk about impact — because we’re using the wrong metrics and we don't want to make some community statement using the wrong metrics.
Erica Walker: To me that just doesn’t make sense. We need to go back to the drawing board and start from the beginning.
Cary: So you and your team I think created an app called ‘NoiseScore’, — how does NoiseScore fit in, how does one use it and how are you applying it right now?
Erica Walker: NoiseScore was released late last year and what we’re doing is…NoiseScore is sort of like the perception piece to all of the research. With NoiseScore you download it, it’s available on iTunes and Android phones, so you download it, you create a noise event. Let’s say you’re in a restaurant and it’s really loud. So what you do is you can record the sound level in decibels and then after you record that, you then want to know some questions about how the sound is making you feel.
Erica Walker: We want to know where you are, we want to know if you’re indoors, we want to know if you’re outdoors, we want to know how active it is, we want to know what are some of the dominant noise sources in the background. And we want to know if this is stressing you out, or is it relaxing you. Do you feel like this is sound, or do you feel like this is noise?
Erica Walker: We’re taking that data and then eventually I would like to use this data to be able to understand what are some of the determinants of noise perception.
Cary: I’m sitting right now looking at the app and I know when I opened it I thought well this is a really great idea, there are a couple of things I wasn’t sure. How do I use this? Or is this something I need to interact with? So for example, you can load the app and look at a map and there’s kind of hot spots on the map already, it looks like these are places where people have already reported in… for example, like I see Chicago, Toronto, looks like Georgia, maybe Atlanta. How does one, a layperson who wants to contribute to this, do they use some of these, there are some menus that say noise perception, layers, filters, so these are things that they can actually adjust and then send a report to you? Or—?
Erica Walker: Yeah, you send a report, organize around it and show this data to— Sorry I work in a very loud—[sirens]
Cary: That’s perfect.
Erica Walker: So my office is in a medical campus.
Cary: I have noticed that I’ve heard a lot of sireny-type things since we’ve been talking.
Erica Walker: Yeah, so right next door to me is an emergency room.
Cary: Oh my God, speaking of having your stress level go up. I mean, do you eventually think “I’ve heard 35 sirens today, I’m chilling now, it doesn’t even bother me” or does it get you every time?
Erica Walker: No, it gets me every time. I have not gotten used to this. Anyway, so I think that, eventually we’re gonna open source all this data, we’re in the piloting phase of this app, but we want it to be used as a tool for advocacy. You can organize around your community, around a certain issue. You can say, you know what, we’re really bothered by aircraft noise, we’re really bothered by this restaurant that’s just super loud, and then you can use this as data to present, at a public hearing or to your city council person. Eventually when we iron out all the kinks, we’re going to release the data. The community can analyze the data in a way that works for them, and they can use this as an advocacy tool around any sort of noise issue they have in their community.
Cary: There’s a couple of apps that are around and maybe using all of them for different purposes is kind of ideal, so for example, this one it’s not limited to being indoors or outdoors, it’s any number of different options. Plus you have the perception factor and then there’s ‘SoundPrint’ for example, which seems like mostly reporting on restaurant noise and then there’s a ‘Hush City’ app which I’ve yet to explore, which is like ‘quiet places’.
Erica Walker: Exactly. And all of this is data that can help to advocate for your cause. You know how, say like you were saying in your apartment, you were trying to look for products to help you in the situation. I think that we should utilise all of the tools out there that are available to us to stake our claim.
Cary: I think so too. I think a lot of people still don’t really know a lot about acoustics, in a way it’s a very rarefied field. In fact, I think it’s a great field to get into.
Erica Walker: I agree.
Cary: Because the lack of awareness of acoustical impact has reached a crescendo I think.
Erica Walker: I agree.
Cary: For example, I live in San Francisco and there’s a lot of development going on, and no one really thinks about the acoustics of — there’s a lot of hills in this city. And when you have hills and you build really tall buildings so they can have fabulous views, you’re also creating an amphitheater, for all the neighbors around you. And you have all this wealth coming into this city, building all these tall homes with floor to ceiling glass for the views on multiple floors. And what this is creating is this unbelievable acoustic environment that’s not good.
Cary: If somebody four blocks away is having a party on their balcony at two o’ clock in the morning and everybody’s enjoying the view and really drunk and looking out and talking — you can hear them really far away.
Erica Walker: Exactly.
Cary: And city planners, they’re considering a number of things, how much of the land is the property going to sit on and how much open spaces there are and that sort of thing. But they’re not looking at the impact of what’s going to happen to noise in the neighborhood if you build these things a certain way, and it really does make a difference.
Cary: The second thing is in the construction industry itself, I think your average construction crew, they’re not trained in acoustics, so they come in, they’ve got specs. Maybe there’s now a requirement in that area for putting insulation in the walls. Maybe they’re not considering whoever’s planned that project what’s the best kind of insulation to use that’s going to really absorb sound. And the default is -- if you’re lucky -- you might get fiberglass. Fiberglass isn’t really the most effective noise reducer as it turns out, so how do you get people educated at the point when you actually could do something about it, whether they’re remodeling or they’re building a new apartment building or something, so that it’s built so that it doesn’t create even more issues.
Cary: The third thing is as a consumer, or a apartment dweller or whatever, once you’ve moved in to one of these things and you find out…and again, you don’t know when you go look at an apartment and you’re going to move in, maybe the neighbor with the toddler isn’t home right then and you don’t get to hear that. You sign the lease and there you are, so what can you do once you’re in and you don’t own this. Or even if you do — how do you deal with this issue?
Erica Walker: For me I’m taking it, I believe in going back to the beginning. For me I’m focusing on using the right metrics to, because if we’re not using the right metrics we can’t properly answer any of these questions, so I want to take it back from the beginning and I want to think about, well what are the important attributes of sound and what are the important attributes of noise? Only then can we begin to have this conversation about regulatory policies and so forth.
Cary: So your site began I think and your project began in Boston, but the app and the site itself is primed to go nationwide. Are there any communities in particular that you wanna focus on as you expand your project?
Erica Walker: Yes. It’s so funny. This interview is relaxing because I’m talking to someone who gets it. It’s also really stressful because there’s a list of things that I need to do. So the answer is yes, there are many communities who have reached out to me and who want to get to work on these issues. So yes, yes, yes. It’s one of the many lists of things on the list that I need to do, but you know these things cost money. This project I did by working three jobs, and people who believed in it worked for free. But the reality is these things cost money. So I’m at the point now where I’m trying to find money to be able to expand this project in the way that is useful and beneficial. Yes, yes. There’s a line out the door.
Cary: We probably don’t even know the half of it, we’re just a couple of city dwellers but imagine there might be issues in smaller communities or in cities that don’t get as much attention. I think it’s an economic issue also.
Erica Walker: Yes, you know it’s really funny, I’ve talked to some communities that have a high immigrant population and they live in— it’s really crazy. I’ve been to these communities and I’ve seen these houses that are literally the balcony is overlooking a major highway. The people who live there probably are most likely undocumented. And the last thing that they want to do is bring attention to some sort of legal authority about a noise issue. So they just kind of suffer through it in silence because they have a whole bunch of other issues to be worried about, where if they notify some sort of authority it can mean a whole bunch of other things.
Cary: Yeah, exactly.
Erica Walker: So there’s a whole bunch of people who are just very disempowered by this because they have a whole other set of issues.
Cary: That’s an important thing as well, and that’s getting into the economics of the issue. Also we have basically a housing crisis going on in the country. And once you’ve moved into a place in some areas you don’t wanna let go of it no matter how bad it is. Because, I don’t know about Boston, but I know there are many areas where you have rent control that goes away if you move to another place and then you pay the market rate someplace else, which is now exceeding many people’s salaries.
Erica Walker: Exactly, I work three jobs and one of my jobs is just to pay rent. It’s like “Okay, I’ve paid rent and now I have to work two other jobs to pay bills and eat.” It’s crazy. It’s really crazy.
Cary: It is. It is and it’s something that’s been happening for a long time but I think that it’s accelerated in the last few years. And so you combine the sound of development outside which is a lot of our noise and the fact that not only do they not plan and think about the impact of acoustics of taller buildings… But also what doesn’t get coordinated sometimes is how many of these projects are going on within a very small range of…in the same zone, at the same time. Because you can actually exceed the sound barrier. If you have enough projects going on and enough jackhammers all running at the same time, and we’ve had that happen. Or you have no egress to the neighborhood because it’s all blocked by cement mixers that are all rolling, and that has its own sound.
Cary: Who’s co-coordinating all this and what can you do about it? Again, you might think this is a great neighborhood, it’s very residential compared to where I used to live, it’s kinda quiet and stuff. And the next thing you know three projects start up. And I think there needs to be an awareness and an education, even for city planners. Things that they need to consider important. And it may not matter to someone till they have it happen to them.
Erica Walker: You hit it, because didn’t happen to me until I experienced it. Just be real, right, I didn’t even think about sound until I got into a situation and it impacted me directly. It’s true. I think we’re on the upswing of things, kind of like the person who thought that "hey, maybe the world should recycle", right? Now we recycle without even thinking about it. So I think we’re going to have the same struggle but I think we’re also going to have the same outcome.
Cary: The same thing, I think you mentioned this one too in one of your interviews, second-hand smoke. You don’t now sit in a restaurant or at your office. I mean in my parents’ generation you might have had somebody smoking at the desk next to you. I can’t even imagine that. So I think you’re right and I really applaud your efforts and really want to see you succeed in moving on this.
Cary: Ultimately in the next couple of years, what’s your number one goal? It sounds like it is educating people, making them aware with these different measurements. Do you have one thing in particular you wanna tackle beyond that?
Erica Walker: You know I would really like to understand more about how perception impacts our health, because we have many epidemiological studies that show how loudness impacts our health, I would really like to be able to show that our perception of sound can also impact our health, and then I would just like to help communities rally around some sort of issue and give them the tools and the support and anything they need to actually solve the problem.
Erica Walker: One thing we as researchers do, we publicize problems, but we don’t solve them. We’re like, look, air pollution’s bad for your health and then we’ll go back to our office and look, noise is bad for your health but wanna deliver tools that people can use to advocate for change.
Cary: Is there anything else that you want to add to this? Anything you want to share with listeners on what they could do or what’s next?
Erica Walker: For those who are suffering, make your voices known I think, that’s gonna be the most important thing. Just don’t feel like it’s a sacrifice that you have to make because you’ve chosen to live next to or live in an urban environment or live next to...or like a kind of sacrifice that you have to make to make an exchange for convenience. Make your voices heard. Because the more voices we have, the more awareness we can bring to the issue. And please reach out to me, I’m a very accessible person. And if you feel like no-one’s listening, I’m definitely listening.
Cary: That’s great. And they can reach you through the Noise in the city.org site?
Erica Walker: Yes.
Cary: Terrific.
Erica Walker: Or they can email me, feel free to provide my email. I’m a real person and I love to hear people’s stories and I love to help them advocate for change.
Cary: Great, thank you so much and I really appreciate you taking the time to talk to me today and I’d love to help you also and help in this effort in any way I can. Anyway, thank you, thank you for everything you’ve done and I’m sure that people in Boston will benefit greatly from the work you’ve done already.
Cary: I’d like to thank Erica for her work and for her generosity and her efforts to help us quantify some of the noise issues we face. As she said in this podcast she’d like to hear your stories, you can contact her through her website…noiseinthecity.org.
Cary: There’s a form on the Contact Us page, or you can email her directly at edw266 at mail-dot-harvard-dot-edu.
Cary: Thanks Erica and thanks to all of you for listening.