It was an abandoned nuclear power plant. Now he has a second life as the most silent acoustic laboratory on the planet

Two gigantic cooling towers of almost 150 meters high flank what clearly seems to be a nuclear power plant in a rural Washington area. It is actually the acoustic laboratory NWAA Labs, one of the most silent buildings on the planet.

An abandoned nuclear power plant. The laboratory was built on the vestiges of a pharaonic project that never saw the light, the nuclear washington Projects of Elma. Plants 3 and 5, part of what was intended to be the largest nuclear energy complex in the United States, were abandoned in the 80s without fissting a single atom.

Designed to resist all kinds of impacts and earthquakes, the structures would have been extremely expensive to demolish, so the NWAA Labs adapted to them. The reactor is the reverberation chamber, the turbine room is the anecoic chamber and the old reactor control room is the laboratory control room. The facilities, still marked, remain a “disturbing” maze.

The ideal facilities. The NWAA Labs is a project by Ron Sauro, an electrical and mechanical engineer formed in Stanford that combined its beginnings in NASA with being the keyboardist of the group The Rivieras, authors of a gold record in 1963. After a life designing sound systems, Sauro saw the unique potential of this nuclear power plant abandoned to bombing proof.

The outer structure, with walls of 1.5 meters thick and eight layers of reinforcement bars, is designed to support an earthquake of magnitude 10 and the direct impact of an explosion of 10 megatons on its roof. The interior structure is isolated from the surrounding terrain by a ditch that minimizes the transmission of vibrations and noise.

In another ditch within this, a circular and steel circular container is erected, originally intended for the nuclear reactor. The entire installation rests on a sandstone layer of more than 3,000 meters thick.

An almost absolute silence. Thanks to these structures, the NWAA Labs presumes to have the two largest reverberation cameras in the world. Salas where the sound bounces up to 28 seconds without absorbent material, which allows to measure the sound power of a source or the absorption capacity of a material.

In addition to the reverberation cameras, the laboratory has anechoic cameras designed to absorb sound and simulate a space without reflections. In these rooms, silence is almost absolute. The background noise is -43 dB (below the human hearing threshold). In the old turbine room, 198 meters long by 106 wide by 24 high, the reflections take so long to arrive (more than 160 ms) that do not interfere with some measurements.

Who uses this laboratory. The NWAA Labs performs tests for the audio industry. The speakers are 20% of their business: over here more than 3,000 speakers of some 300 professional brands and high fidelity have passed.

But it is also offered to other industries, which prove construction materials, acoustic insulation here, and even noisy washing machines or aircraft cabins. The laboratory also attracts musicians, video game and filmmakers, fascinated by their acoustics and post-apocalyptic aesthetics.

Image | Walter Siegmund (CC By 2.5)