Noise control in laboratories

Abstract

ASHRAE Ch. 49 is a leading industry reference in noise control, providing extensive guidance on background noise levels, as well as practical noise control methods. The design guideline for background noise criteria in laboratories ranges from NC 35 to 50 depending on the expected activity. Noise control guidance for laboratories predominantly addresses fume hood design. In practice, recent workplace projects have included laboratory spaces without fume hoods; and background noise levels that are not necessarily controlled by the HVAC systems. The modern definition of “lab” space can include machining and fabrication (makerspaces), workplace server labs (server / chip design), and R&D testing suites for consumer electronics with various microphones/speakers. Accurate estimate of the overall background sound level in the lab is critical in determining appropriate criteria and noise control and avoiding unnecessary cost additions to a project. In some cases (such as makerspaces), ambient noise levels of idling equipment may exceed general ASHRAE guidance and still be acceptable to the occupants, even for a teaching application. In other applications (such as R&D testing), appropriate noise criteria may be significantly lower than ASHRAE’s guidance. This presentation will discuss recent observation and design experiences in evaluating noise levels and noise sensitivity of makerspace, server chip design, and R&D laboratory spaces.