Sound of Silence is Music to Neighbors' Ears
There was no brass band or wild applause when the doors to Cummins’ Acoustical Testing Center (ATC) first swung open to the public last fall. Instead, visitors were greeted by silence.
Silence is precisely the point of the Company’s new sound-testing facility in Fridley, Minn., built next to the Cummins Power Generation (CPG) plant. With its curved roof and sound-absorbing acoustical wedges lining the walls and ceiling, the distinctive-looking center is the largest facility of its kind in the industry.
The facility is expected to significantly change how Cummins does its sound testing. By working in a controlled, indoor environment, unwanted noise is eliminated leaving just the sound from the generator itself to be precisely measured.
Noise is an environmental issue that is becoming increasingly important as customers and government regulators demand quieter power systems. For instance, the electrical industry publication Electrical Products & Solutions chose a Cummins Onan residential generator as one of its Top Products in 2010, noting that the RS20A/AC model was the quietest of four competitive models.
In the United States, the first federal law regarding noise control was enacted in 1972, though noise is regulated at the local level today. The European Union has specific noise limits through a 2002 directive, and a recent report to the European Parliament and Council called environmental noise a “significant environmental problem across the EU” due to its health impact.
“Noise really is an emission because it influences the environment in which people live,” explained Martin Myers, Cummins Director of Global Applied Technology and the primary user of the new facility which opened in October of 2011.
He says the new building is also making the surrounding neighborhood a quieter place.
“We really want to be a good neighbor,” Myers said. “By building this building, by putting the investment in, we are no longer affecting our neighbors when we are running generator tests.”
The black, red and white wedges that line the center’s interior chamber are filled with sound-absorbing insulation material and enclosed in a perforated metal shell. The ceiling is curved to allow sound to dissipate rather than be reflected as it does off flat surfaces.
“The chamber itself is basically an instrument,” said Kevin Wiese, the project manager who oversaw the construction.
The testing center also allows for greater opportunities in research and development. Pinpointing the sources of noise in a generator helps Cummins Power Generation design quieter products.
“It will deepen our knowledge of noise sources and help us design quieter, more cost-effective products for our customers,” said Tony Satterthwaite, CPG President.
The facility was built in accordance with Leadership in Energy and Environmental Design (LEED) guidelines for green building design. The heating system is 82 percent efficient and electrical consumption is less than the LEED requirement.
More than three-quarters of the construction materials have been recycled or salvaged. The building materials include recycled or partially recycled metal paneling, fly ash concrete and locally sourced materials such as steel made from ore mined in northern Minnesota.
In addition, the center was built on a site that qualifies as a brownfield redevelopment by the U.S. Green Building Council. Brownfields are land previously used for manufacturing that can be difficult to redevelop. The U.S. Environmental Protection Agency promotes cleaning up brownfields and finding new uses for them.