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Making Noise About a Quiet Data Center

- March 11, 2015 - 6 Comments

I like touring Data Centers. Whether it’s a makeshift space with out-of-control cabling or a state of the art, innovative facility, I’m always curious to see how companies accommodate their computing equipment and tackle the inevitable challenges of space, power and cooling.

Ten years ago I visited a then-new Data Center in the western United States that had several interesting features.  Two elements – and the moments I discovered them – still stick with me.

Look out below. Electrical conduits, data cabling and cooling were all routed beneath the Data Center’s raised floor – very conventional. As I entered one of the room’s cold aisles and glanced at the perforated tile under my feet, though, I was startled to see the basement floor about 15 feet below. The Data Center’s air handlers and power distribution units were down there and with air flowing up through the tiles, designers saw no reason to install a true floor for the ground level. It’s not a design choice I might make – an open floor tile in the data hall poses a potential safety hazard – but it was certainly interesting to see.

Can you hear me now? Perhaps even more surprising was that the data hall was whisper quiet. With the air handlers in the basement and hardware fan noise masked by the room’s hot aisle enclosures, it was easy to have a quiet conversation while strolling among the server rows. Having working in and around Data Centers for a handful of years by that point, I found it almost eerie.  In my experience server rooms were only silent during an outage.

Quiet Data Centers still aren’t the norm these days. Check out the video below – no ear plugs required – for a stroll around the noisier locations in a Data Center, and a discussion of what can be done to lower the volume.


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    You know your raised floor is high when you start considering a separate lighting system for the plenum space...

  1. Douglas, a 15 foot raised floor IS pretty high, and you are right: it becomes a safety hazard... "Where did that database guy go to?" "Oh, I think he fell through a perf panel... maybe he's down there somewhere!" At Netfloor USA, any raised floor over six feet and we like to have a serious conversation with the owner, architect and engineer about safety. We did a pretty large data center project that called for 10 foot raised floors and we did questio the reasoning. But, the depressed slab had already been poured, so there was nothing to do, besides put a few rows of caution tape near the edge of the access floor as the install progressed, and to keep other trades up to date on the risks involved if they worked in the same area as us. We did use adhesive and 4 concrete anchors for every pedestal, but were still concerned with the sheer height of the floor if some panels were removed. The air velocity under the floor WAS pretty low, and most areas of the data center were quiet. I guess that's a safety factor: if you fall through the raised floor and it's quiet, SOMEONE might hear you hit the bottom! jk :)

    Hi, Vivek. I recommend doing a quick online search for "hot aisle containment." There are multiple solutions on the market, not to mention chimney cabinets that do the same function on a by-cabinet basis rather than by row. They all serve to isolate hardware exhaust from incoming chilled air, allowing a Data Center's cooling system to operate more efficiently.

    Thanks, Rich. Yes, rotary UPS systems are nifty, but quiet they definitely are not.

    That is news to me and I am impressed that the noise level has been cut down so drastically. Would like some more information about the hot aisle technology as mentioned in this blog article.

    Very nice overview. And Wow. Had no idea the rotary backup generators were THAT noisy.