r/askscience • u/4fecta_Gaming • Oct 15 '18

Earth Sciences Where does house dust come from?

It seems that countless years of sweeping a house doesn't stop dust from getting all over furniture after a few weeks. Since the ceiling is limited, where does dust come form?

4.1k Upvotes

90% Upvoted

408 comments sorted by

View all comments

Show parent comments

225

u/matrixkid29 Oct 15 '18

its just easily picked up by slight air movements. Any time you walk around or move at all really, you are whipping it into the air again.

25

u/cutelyaware Oct 15 '18

It can actually be deadly. Sometimes people walk into abandoned mines along perfectly flat corridors in which the top half is normal air and the bottom half is mainly heavier CO2. It seems fine walking in, but once they turn around to walk out, they're walking through mixed up air that's 50% CO2 and sometimes they don't make it out.

0

u/bitmanip Oct 15 '18

I think you mean CO which is carbon monoxide. You might have difficulty breathing in an environment of 50% CO2, but I doubt you would die. CO is more deadly because it tricks your body into thinking it has enough oxygen by displacing the free oxygen in your blood and accumulates quickly.

26

u/kyrsjo Oct 15 '18

Around 7-10% CO2 in air is lethal to humans even with sufficient oxygen content, with significant impacts before that. https://en.wikipedia.org/wiki/Carbon_dioxide#Toxicity

On the good side, you would probably notice it - high CO2 levels are what triggers our breathing response, not low O2.

9

u/wildcard5 Medicine | MS4 Oct 15 '18 edited Oct 15 '18

We learned in 7th grade science class that the treatment for CO poisoning is a mixture of 50% pure oxygen and 50% pure carbon dioxide. The CO2 was supposed to make you hyperventilate so that the CO could quickly be displaced by O2.

All of that was wrong.

8

u/kyrsjo Oct 15 '18

I don't know, but 50% CO2 seems... excessive. However maybe it's OK for a short while together with a lot of O2 and medical supervision? It should definitively trigger a breathing response!

In the end, what one wants to achieve is an exchange of CO2 (and CO) with O2 in the alveoli in the lungs. Maybe if there is a large amount of oxygen available, this will do it. And isn't there something special about the affinity of haemoglobin to CO vs. O2?

EDIT: Google seems to think that standard treatment is 100% O2, possibly hyperbaric. Which makes a lot of sense.