Sound levels inside spacecraft are controlled by means of on-orbit acoustic emissions requirements that support hearing conservation, speech communication, and mission safety goals. These requirements, which pertain to science experiment payloads and other flight hardware, also prevent noise-induced vibrations from deteriorating the on-orbit microgravity environment.

Flight crew members are included in a comprehensive hearing conservation program managed by the Audiology and Hearing Conservation Clinic at NASA's Johnson Space Center. The ATL supports the Flight Crew Hearing Conservation Program by providing educational and training resources and services, customized medical illustrations, and expert acoustical consulting.

On orbit noise levels are managed by the Acoustics Office at Johnson Space Center.

For more information about on-orbit hearing conservation issues, see the following publication:

Cooper, Beth A., Danielson, Richard W., Clark, Jonathan B. and Stevens, Christina J. "Global Auditory Concerns for Individual Needs: Expanding the Hearing Conservation Universe to the International Space Station." Proceedings of the NHCA Conference. Feb. 2002. (.pdf file)

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