Walk through most industrial facilities and you'll hear it before you see it - low hum from the plant room that's been “just how it sounds” for years. Facility teams get used to it. Maintenance logs stop flagging it. And that's exactly the problem! AHU fan noise and vibration rarely show up as an emergency. They show up as a slow leak: In energy bills In bearing life In comfort complaints, nobody quite traces back to right cause. It's also one of the more under-covered topics