HUANG: CONSIDER THIS - nearly 1 in 3 Americans are regularly exposed to excessive noise. As communities get louder, some are fighting back - pushing for more regulations to create quieter and healthier cities.

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HUANG: From NPR, I'm Ping Huang. It's Friday, August 18.

It's CONSIDER THIS FROM NPR. Noise is something many of us have learned to live with. We just tune it out. But noise researcher Erica Walker says that that complacency can be a problem, especially in places with chronic noise pollution, because it's affecting our health. I've spent years learning how to block out the din of daily life, and now I wanted to learn how to unblock it to understand just how much noise we live with. So I went on a sound tour with Walker. It's the middle of the day in the middle of the summer.

ERICA WALKER: We're in Kennedy Plaza in downtown Providence, R.I.

HUANG: We're in the middle of the city of Providence where Walker is a noise researcher at Brown University.

WALKER: You got people, transportation, music. This is just, like, quintessential urban environment.

HUANG: She studies how noise pollution affects people's health. Our first stop is the bus depot, where we meet a woman named Keisha (ph) who asked us to only use her first name because we were discussing what is a contentious issue in the community - which is sound. She doesn't mind the way the city sounds.

KEISHA: Trees, wind, buses, people, birds, public (laughter) - I can't complain. I'm just trying to get to work.

HUANG: Here, the sounds are temporary, but it's the noise at home that's the problem.

KEISHA: Businesses with loud music - it's ridiculous - all hours of the night. It's crazy. Call the police - nothing gets done. I can't sleep with a speaker coming out of a SUV till 7:00 in the morning.

HUANG: Noise pollution is unwanted sound, and it can affect the body in a few different ways. For those who live or work in very loud places, it can damage their hearing. But Walker says it can still affect their health.

WALKER: It's that - yeah, it's that response of calling 311 over and over and over again. It's the, I can't sleep at night. It's the, I feel like I'm going to have to sell my house and move out. It is the, I had to go to the emergency room because I had a panic attack. It's, I can't sleep. I can't hear my children. It's all of those things.

HUANG: Chronic noise exposure in places where you live can put your body in constant fight or flight mode. It can lead to hypertension, heart problems and a decline in mental health. Walker came to this work because of her own experience. Years ago, she was living in an apartment in Boston.

WALKER: A family moves in above me with two really small kids. And, of course, those two very small kids ran across their floor, which was my ceiling, for, like, 24 hours a day.

HUANG: While it sounded like joy to their parents, it was a constant stressor in her life. She documented the noise, started recording her stress levels and even collected her saliva to test for stress hormones.

WALKER: When I go hard, I go hard.

(LAUGHTER)

HUANG: Her goal was to get the family evicted until a trusted friend channeled her frustrations into the fields of public health, helping communities deal with noise. Next, we head to a residential neighborhood.

WALKER: So we're in a really posh neighborhood off of Blackstone Boulevard in Providence, R.I.

HUANG: We're standing in the shade of a leafy tree next to a beautiful lawn. You can hear the low hum of air conditioning, and you can hear the birds.

WALKER: I just feel like everything just slowed down considerably. You know, you hear an occasional dog barking. Cars drive by slower. You feel like you can just hear yourself think.

HUANG: Walker says that this is the sound of privilege and that this quiet should be something everyone gets in their lives. But we are standing in a neighborhood of million-dollar homes. It's where a lot of professors live, though not Walker.

Erica, should we head to our last stop?

WALKER: Yeah, absolutely. I'm ready.

HUANG: Where are we headed?

WALKER: We're headed to Pawtucket, R.I., which is where I live.

HUANG: The impacts of noise pollution can't be fully captured in decibels. That's what Walker's research shows. A few years ago, she did a study on people living near Fenway Park, which is an open-air baseball stadium in Boston. On game days, there's music. There's announcers. There's military aircraft flyovers.

WALKER: So yeah, they can be extremely loud, but it was something that the community agreed to, right?

HUANG: But when the stadium was used as a concert venue, the neighbors got upset, even though the volume of the sound was about the same.

WALKER: People were like, we didn't sign up for this. The emotional response to the concerts was just outrageous.

HUANG: Walker found that the source of the noise and whether people felt like they had agreed to it matters a lot.

WALKER: I'm more concerned about the emotional responses because I feel like that is what's driving the health impacts.