How much sound do data centers create, and how is it regulated?

Data centers produce continuous noise from cooling equipment (chillers, cooling towers, HVAC fans) and periodic noise from backup generators during testing and outages. Cooling equipment typically produces 75–85 dBA at the source, dropping to roughly 60–80 dBA at the property line and lower with distance. This is equivalent to the sound of a normal conversation.

Backup generators are the loudest sources, but they are only deployed in cases of emergency and for a few minutes during monthly testing.

Noise is regulated locally. For example, Loudoun County, Virginia — the largest data center market in the world — caps noise at 55 dBA at the receiving property line, with stricter 50 dBA daytime / 40 dBA nighttime standards in newer zoning categories. 50 dBA is the same as a quiet suburban neighborhood, while 40 dBA can best be compared to the hum of a refrigerator.