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Comment by niccl | Hacker News Reader

I can't tell if this research still applies. There currently appears to be an emphasis on CO2 as a particularly Bad Thing, but the research in this paper suggests that CO2 is less of an issue than just temperature in deciding whether a space is pleasant or unpleasant to work in

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Thermal comfort is still the number one thing. Visual comfort (primarily glare, but also the frequency spectrum of the light/overall light levels matter too) and ventilation do matter too though. Everybody knows what it’s like to be in a crowded lecture hall with poor ventilation and high CO2 levels leading to drowsiness!

There’s been a big boom in research related to dispersal of things (CO2, biological materials etc) lately though due to the increasing accessibility of CFD to building scientists + COVID.

> Thermal comfort is still the number one thing.

Thermal comfort isn't as simple as many people think.

Your wall thermometer may give you a reading, but that may only be perhaps half of what you feel in a room. Another large portion is radiant heat emanating from all the objects (furniture, walls, etc) around you:

* https://www.buildinggreen.com/blog/understanding-and-measuri...

It's why in an office people can feel cold and complaint to the the facilities folks, but when they should up with a thermometer it reads the 'correct' room temperature (21C or whatever)—the thermometer isn't taking into account the giant glass office windows that are acting like 'anti-radiators' in the winter.

Further, if the temperature is correct, but the humidity is 'high' (>60%) then things will feel hotter:

* https://en.wikipedia.org/wiki/Psychrometrics

* https://www.ashrae.org/technical-resources/bookstore/psychro...

If you live in an area where it can get humid, it's worth considering getting a whole home dehumidifier: if the temperature is 21C but it's humid, the AC will not kick in—you need an hygrometer (RH%) too.

Haha, yes I know! You also have airspeed, perspiration, metabolic rate, clothing levels, and transients (eg moving from a hot space to a cold space) which all affect the phenomenological experience- but we do consider all of these effects to be wrapped up within the “thermal comfort” term of art.

See the CBE Thermal Comfort Tool to interactively determine comfort bands in relation to various ASHRAE standards for computing thermal comfort with all of these affecting parameters:

https://comfort.cbe.berkeley.edu/

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