NIST researchers develop spherical chamber for testing building and construction materials

JOM, Aug 1998

A Chicago company recently signed an exclusive license to a U.S. National Institute of Standards and Technology (NIST) invention that tests a wide range of organic building and construction materials. Atlas Electric Devices Company signed the license to the invention that uses a spherical chamber instead of the previously used cylindrical version.

Many companies use ultraviolet chambers to induce artificial weathering of building and construction materials to estimate durability over long periods of time. However, these test results can be inconsistent and difficult to replicate.

Researchers at NIST's Building and Fire Research Laboratory produced a novel way to get better results by using integrating sphere technology. The spherical chamber has a reflective inner surface that scatters ultraviolet light evenly, producing a uniform field of radiation. The sphere can be outfitted with apertures, which allows adjacent chambers to receive precisely the same amount and intensity of ultraviolet light. This lets researchers test several different samples of the same material under precisely the same ultraviolet light conditions while independently controlling other factors, such as temperature, humidity, and mechanical loading.