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My kid will get nosebleeds if the air is too dry, so I run humidifiers. Ventilating means I lose my hard won humid air. Any solutions?
My kid will get nosebleeds if the air is too dry, so I run humidifiers. Ventilating means I lose my hard won humid air. Any solutions?
There are heat-exchanging air exchangers for high-efficiency construction. I'm not aware of (and don't find) humidity exchanges, though they may exist.
Hung dampened linens (towels, bedsheets) can make a big difference. Many HVAC systems offer high-efficiency humidifiers, and the old standbye of having a kettle on the stove can work (with an energy cost).
Humidity in general is fairly cheaply acquired. Dehumidifying moist air takes much more energy.
Earlier quoted context omitted.
I picked up a CO2 monitor a while ago myself, and the biggest surprise was having it on in the morning in our bedroom with the doors closed. It was easily over 1000ppm IIRC. Ever since then I've made sure to set my AC system to run the "house fan" for 15 minutes or so every hour at night just to circulate the air in the house, and while the numbers went down significantly, anecdotally I swear that I wake up easier in…
Helmets? That's interesting; I tend to open the visor a bit when at a stop, it gets really warm in there really fast. I know you shouldn't try to take off a helmet in case of an accident, but is opening the visor at least okay?
My kid will get nosebleeds if the air is too dry, so I run humidifiers. Ventilating means I lose my hard won humid air. Any solutions?
(yes I know this is not a practical solution)
Earlier quoted context omitted.
How does air recirculation with increasing co2 compare to having to breath/smell car exhaust, cigarette smoke, etc through vents? I started doing recirculation as my default years ago due to that.
Isn't that just... what outside smells like? What do you do about smelling people's breath in the air (??) whenever you exit your car?
No. I wrote up the computations explaining why. See http://www.moderndescartes.com/essays/co2_closed_rooms/
> At 5 millibars (5,000 ppm), you would start breathing at a 10% elevated rate, which you probably wouldn’t notice. Wouldn't you? Won't you subconsciously notice and want to end the meeting faster? Imagine breathing at an elevated rate in a crowded room that lacks proper ventilation. There's more than co2 coming from the human body. People will begin sweating, farting, etc., and fill the air with all kinds of polluta…
Your description makes me think of the opening scene from Falling Down.[0]
No. I wrote up the computations explaining why. See http://www.moderndescartes.com/essays/co2_closed_rooms/
> At 5 millibars (5,000 ppm), you would start breathing at a 10% elevated rate, which you probably wouldn’t notice. Wouldn't you? Won't you subconsciously notice and want to end the meeting faster? Imagine breathing at an elevated rate in a crowded room that lacks proper ventilation. There's more than co2 coming from the human body. People will begin sweating, farting, etc., and fill the air with all kinds of polluta…
I own a CO2 monitor and it is shocking how high it can get in a house with two people just existing. 800 ppm or more. Outside air is 410. In a car with air on recirculate, it was getting to >1220 ppm, a level that impairs decision making and lowers brain function. I try to drive with air on fresh from now on. I don’t doubt the air in our conference room with 20 people gets super high in CO2 as the meeting goes on, an…
I picked up a CO2 monitor a while ago myself, and the biggest surprise was having it on in the morning in our bedroom with the doors closed. It was easily over 1000ppm IIRC. Ever since then I've made sure to set my AC system to run the "house fan" for 15 minutes or so every hour at night just to circulate the air in the house, and while the numbers went down significantly, anecdotally I swear that I wake up easier in…
It seems that any sort of face covering or even significant exercise could raise your ambient CO2 level well above 1000ppm.
I'm a bit surprised that levels 38-60x below our exhalation % (and it's not lack of O2, because you use up less than 10%/breath) has such a significant effect. The one thing that may drive it is that the efficiency of lung ab/desorption goes roughly as the square of concentration so a 2% change in CO2 concentration might be enough to have an effect on O2 and blood pH.