news-record.com

GREENSBORO — Like a lot of people living near the newest section of the Greensboro Urban Loop, Arthur Ihrig is angry about its incessant noise.

But unlike many in the city’s southwestern suburbs, Ihrig has an edge in understanding the forces that make the loop such a beastly neighbor. He’s a scientist, schooled in making precise observations and logical inferences.

So the retired chemist spent nearly $5,000 for a SoundPro SP DL noise meter last year to study the eight lanes of traffic the way a paleontologist might examine an exotic fossil.

“I’ve always had a scientific orientation,” Ihrig said. “And when this thing directly affected me, I decided I would just start doing a little science once again.”

He hopes his research will help persuade federal, state and local authorities that:

• He, his neighbors in Sedgefield Lakes and other neighborhoods near the loop deserve sound barriers or some other effective buffer.
• Highway planners use badly flawed techniques to decide who is eligible for such noise protection.

The holes in those techniques became the focus of Ihrig’s months-long quest to understand how the loop — 200 feet from the house he bought in 1973 — could be so loud but not merit noise protection.

He found the “A-weighting” scale used by officials to rate traffic noise ignores huge volumes of sound, the kind of low-frequency rumbling from trucks that pierces walls like they aren’t even there.

That technique is based on a format developed in the 1930s , the A-scale, that aims to categorize the general human response to different levels of sound.

“I think they (highway officials) are using bad science,” Ihrig said. “It’s not valid in a situation like this, where you have extremely loud noise with lots of low-frequency sound.”

Ihrig has support from at least one researcher who writes extensively on the issue.

“He is absolutely right,” said Daniel Maguire, a well-known noise expert based in Indiana. “What they (officials) are saying is, 'We don’t give a rip about low-frequency noise.’ Yet because it’s a highway, that’s the thing they should be most concerned about.”

The Greensboro retiree’s findings also resonate with Charles Bruckner, Tar Heel representative of the New York-based advocacy group Noise Free America.

“The A-weighting scale doesn’t do anything for the lower end of the (noise) spectrum that carries farthest and actually penetrates walls,” said Bruckner, a Garner resident.

Ihrig’s efforts are significant because they show a resident going the extra mile to hold public officials accountable, said Les Blomberg, director of Noise Pollution Clearinghouse, which tracks noise complaints ranging such sources as airport takeoffs and car stereos.

“Thirty years ago, that guy could never have done this because he couldn’t have afforded the equipment,” said Blomberg, who lives in Montpelier, Vt.

Ihrig’s noise meter uses specialized computer software to analyze sound data in any of the four measuring systems used most commonly.

Ihrig found that when he used the standard A-weighting system, readings did not exceed the range envisioned by the state Department of Transportation before the road was built.

He can’t do an apples-to-apples comparison because the state’s estimates are based on traffic counts and other data he does not have.

But average noise levels Ihrig measured did not surpass 67 decibels, the minimum for his area to begin qualifying for a sound barrier under federal and state noise rules.

His research does provide a scientific foundation showing that next to his neighborhood, the loop has only two volumes, loud and somewhat less loud.

“There are very rare instances when there might not be a car coming through for a minute at a time,” he said. “Even into the wee hours, you still see significant amounts of traffic noise.”

One night some months back, Ihrig tested his theory after being kept awake by the road’s low rumble beyond his bedroom window.

He got up, turned on his sound meter and found that, using the government’s A-scale, it registered only 25 decibels.

“That’s the sound you’d get in a quiet woods,” Ihrig said.

But when he switched to another measuring scale, the reading jumped to 50 decibels, about the sound level of a nearby clothes dryer, which Ihrig felt was more realistic. The incident shows how lower tones missed by A-weighting can penetrate walls to disrupt daily life, he said.

State DOT doesn’t dispute that the A-scale misses lower-frequency sound. That is not necessarily a drawback, said Gregory Smith, who supervises noise issues for the state DOT.

“What it does pick up are the high-frequency sounds most irritating to people,” Smith said.

But the whole discussion is moot because the state DOT has no choice, Smith said — the federal government mandates use of A-weighting.

Indeed, the Federal Highway Administration requires it as “the best way to capture how the human ear responds to traffic noise” by cutting out sounds people can’t hear, an agency spokeswoman said.

“If the human ear cannot hear the sounds, then there is no need to capture them in the noise analysis,” spokeswoman Nancy Singer said.

That contradicts what Maguire, the Indiana noise specialist, has found over the years. In a telephone interview, he characterized A-weighting as an arbitrary system never meant to be applied in the way federal authorities now use it.

A-weighting stems from research by two Depression-era psychologists who just wanted to see how people perceived different tones at varying levels of intensity, he said.

Knowing lower tones are more difficult to discern, they tested a group of young men to see how much louder a low tone must be before listeners said it was equally loud as a higher-pitched sound.

They labeled one series of these sound relationships the A-scale, it became a staple of sound meters 70 years ago, and the federal government made it the standard for measuring noise inside government office buildings in the 1960s , said Maguire, chief technical officer for a maker of devices to measure and reduce industrial noise.

From office buildings, the A-scale morphed into the yardstick for all types of noise measurements, regardless of whether the noise being measured was similar to what office workers typically encounter, Maguire said.

He suggests emulating other nations that have used modern science to develop more realistic ways of measuring the full range of noise impacts.

Numerous studies show that low-intensity noise is at least as disruptive and potentially harmful to health as higher tones, he said.

Ihrig has seen some of those studies, too. And he thinks that if his neighbors become sufficiently fed up, his data might be used someday in a lawsuit aimed at forcing the DOT to do a better job of insulating them from highway noise.

Ultimately, such a lawsuit might lead to changes in government’s approach to highway noise not just in Greensboro, but nationwide, Ihrig said.

“It’s just common decency,” he said, “to minimize the impact on people who live along a road like this.”

Contact Taft Wireback at 373-7100 or taft.wireback@news-record.com