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On some days our office feels very cold to the point at which we find it difficult to type because our hands have gone numb. But our facilities manager insists it is the same temperature as always.

We have discovered the reason for feeling cold is that the air conditioning causes a draft of cold air. Whoever is in the draft feels more and more cold the longer it goes on.

My question is: Would a thermometer in the path of this draft of air show any change in temperature, and if not, how can this cooling effect be measured so we can provide evidence of our discomfort to our company?

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Try blocking the AC ducts with some peanut butter, that always seems to work. –  DumpsterDoofus Dec 31 '13 at 15:50
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If you feel cold, proving it wont change someone whose mind is made up. Google & Bing don't know about an "Empathastat". So maybe I've spelled it wrong. It takes into account Dry bulb/Radiant temperature and Airflow. A heated copper cylinder, (to represent the human body), cloth covered (to represent cloths). The energy used to maintain the cylinders temperature, is monitored and used for environmental control. –  Optionparty Jan 1 at 3:58
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2 Answers 2

If the draft is coming directly from the air conditioner, then a thermometer might show that it is colder than the bulk of the air in the office. This is because the air coming directly out of the air conditioner is of necessity colder than the average room air when the air conditioner is providing cooling. Eventually that cold air mixes with the existing air and the temperature evens out and the average gets a little colder in the process. Getting some hard data with a thermometer sounds like a good idea in any case.

The solution is to point the stream coming from the air conditioner away from people. Every air conditioner I've seen has at least some louvers for this purpose. Point the cold stream up so that it mixes with the existing air near the ceiling, then the air falling down on the humans will be warmer after the mixing and the flow will be more gentle.

Wind also makes humans feel colder, even when the air is at the same temperature. This is what the wind chill factor you often hear in weather reports is all about. There is a standardized formula that takes into account air speed, humidity, and temperature to model how "cold" it will feel to a human. You could take some measurements and apply this to tell the facilities guy how cold it feels after these effects are considered.

Again though, regardless of what the wind chill measurements tell you, part of the solution should be to aim the direct outflow of the air conditioner away from people. You might also point out to the facilities guy that raising the thermostat temperature when cooling will save power and therefore money. If you feel more comfortable with it set to a higher temperature, then that is a win-win all around.

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Thanks, but we've been trying for years to direct the airflow away from the desks. Problem is we've got more desks than the building was designed for. –  Will Sheppard Jan 6 at 16:08
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A thermometer won't, but an anemometer (wind-speed measurement device) in combination with a "wind-chill factor" chart like this http://www.nws.noaa.gov/os/windchill/index.shtml may help convince them.
If not, point them to articles about evaporative coolers and spray-mist cooling systems, and explain that the same effect happens when air is blown across people's skin.

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