The perfect house: energy efficient, climate-controlled, with sweet filtered air inside. Want one? I don’t. To me, healthy living means opening a window to change the temperature in the house and rejoice in what the environment presents1.
I’m an environmental pig, living in a house designed over a century ago, lacking in the latest energy efficient technology. Instead, I have trees. Trees that shade my home and prevent the sun from beating extra kilojoules of energy, as heat, into my rooms. I have primitive geothermal cooling – an unfinished basement that breathes coolness into my main floor. My grandmother had something called a ‘root cellar’. A root cellar is on the cool side of the house (NE), in an area of the basement surrounded on four of its six sides by earth (top, bottom, north and east walls), and provides sufficient refridgeration to preserve carrots, potatoes and turnips.
Today’s ultimate ergonomic home, controlled with energy saving algorithms, has constant temperature regulation, purified air, and is tightly sealed from the outdoors. This provides cost effective heating and cooling2, and optimum air flow to prevent the growth of moulds and the like, with filters to cleanse contaminant particles from the air.
Sounds great, but I don’t like it. Imagine instead opening a window to the heavenly smell of a summer rain, or when the roses are in bloom, or if the grass has just been cut. Wake in the morning to the sounds of the birds peeping and trilling through your open windows. Feel the caress of a breeze, floating in with the rhythimic chirp of the crickets on a hot summer night. Man, it’s good.
Which is better: the ecological, economical, sealed house, separating us from the nasty environment bent on messing with our equilibrium, or fresh air? Long ago, doctors prescribed fresh air to cure all kinds of ailments, obtained by sitting seaside as ocean gales hurled past. Today, we have polluted air and climate change that superheats and supercools our environment. We also seem to have heighened levels of environmental sensitivity, making many of us retreat into our climate-controlled isolation units.
I think there’s an instinctive attraction to fresh air, perhaps the converse of our repulsion for things that smell of bacteria, yeast or other microorganisms associated with death, disease and decay. When we smell clean water, or air scented with healthy growing things, we know there’s sustaining substances for us. The reek of animal waste makes us recoil, which is surely a good survival instinct, allowing us to avoid traipsing into the bear’s or lion’s den.
Ancient history? Do our instincts lag behind what’s useful in the modern world? I went looking to see if fresh air is still good for us. The first web search turned up organizations confirming fresh air was good for the soul. It cleanses, reduces stress, improves digestion, boosts the immune system and a number of general statements of limited substance. People believe that fresh air is good for us, perhaps based on how good it feels, but how about proof?
Science, where are you? Science says there are benefits to feeling as good as fresh air can make us feel. Fair enough.
One interesting study3 measured ventillation in 28 grade schools in California and compared it to sick days taken by students. It found the higher the rate of removal of CO2, the fewer sick days. This cleansing of the air, associated with less illness, was higher in classrooms with open windows than air conditioning. But that might just mean that traditional air conditioning isn’t very good at air exchange.
What is fresh air, exactly? Anyone who’s familiar with farm country, a bastion of wholesomeness, knows it often smells unpleasantly of manure. Different people might define fresh air as air that’s:
- scented with pleasant things, like apple pie, or the sea,
- has less CO2 and more O2,
- low in irritants, or infectious agents, or
- a comfortable temperature.
Googling ‘allergen free air’ is amusing. The first nine hits are businesses offering sources of air treatment, and the last one is for chimney cleaning4.
On Google Scholar, I found specific, detailed studies, such as:
- dust-free pillow covers reduce allergic symptoms in a group of 30 kids,
- Hepa filters decreased cat dander but did nothing for asthma symptoms in a handful of people,
- fungus is higher inside than out in the winter in the US midwest.
This, of course, is the point. Science is very specific because sometimes it matters very much if you take one acetaminophen capsule today or one acetaminophen capsule per day, so we shouldn’t expect it to provide pronouncements on something as general as fresh air.
The US EPA (Environmental Protection Agency) defines six things5 as hazardous to human health in air (at sufficient concentrations), all based on full arsenals of scientific research. Some of these harmful things are not smellable when you open the window after a summer rain. But I can’t accept that it’s better for people to stay inside a sealed building, even if it has perfect air quality.
Are my instincts betraying me, telling me outside is good? Are they antiquated notions, left over from a time when there was no pollution, climate change or crazy, invisible things in the environment that could harm me?
If my fresh air instincts give me a survival advantage, turning my yearning to spend time outside to increased health and longevity, then they are good instincts. But if those who stay inside are better off, don’t contract as many diseases because they are protected by their controlled environment, then my instincts will fade from the human repetoire. My line will die out while the earth is populated by the people who stay inside.
I don’t know the answer to who will win this evolutionary battle of survival strategies and it will take centuries or longer before anyone knows. The question is whether they will be living in a sealed, plastic dome or in the forest alongside the deer, mushrooms, and snails.
1 At least for half of the year, not when central heating is doing it’s best to keep the indoor temperature above 65oF/18oC, then I’m all about man-made heat.
2 I am told that it’s most efficient to control the temperature 7×24, rather than adjust it at will, as keeping the temperature constant is less energy intensive than sudden changes.
3 Mendell, M. J., Eliseeva, E. A., Davies, M. M., Spears, M., Lobscheid, A., Fisk, W. J., Apte, M. G. (2103) Association of classroom ventilation with reduced illness absence: a prospective study in California elementary schools. Indoor Air v23(6) doi10.1111/ina.12042 retrieved from http://onlinelibrary.wiley.com/doi/10.1111/ina.12042/abstract
4 Probably because I have a wood burning fireplace and was looking for someone to clean it recently, but an admirable example of how sweet the smell of something (burning hardwood) can be but how unsure I am that it’s healthy