2952: Routine Maintenance

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Routine Maintenance

Title text: The worst was the time they accidentally held the can upside down and froze all the Earth's magma chambers solid.

Explanation

This explanation may be incomplete or incorrect: Created by an ONCOMING LETHAL DUST CLOUD - Please change this comment when editing this page. Do NOT delete this tag too soon. If you can address this issue, please edit the page! Thanks.

A recommended routine maintenance step for many electronics, such as desktop computer towers, is to remove the buildup of dust on a regular basis. This bit of routine maintenance can help prevent the electrical components from overheating, and lengthen the lifetime of these electronics. There exists cans of high-pressure gas, as depicted, to blow dust out without a person blowing themselves, thus allowing them to keep their distance and not get a faceful of dust, or adding unintended moisture to the electronics.

This is suggesting that this is a maintenance step performed on the Earth itself, blowing gas into the Earth to force out the dust. However, filling the atmosphere with dust would be unhealthy and fatal to living beings, so as a safety measure everyone would have to take shelter. This is a reference to one theory about the extinction of the non-avian dinosaurs, that a crashing meteor sent so much dust into the air that it killed off all non-avian dinosaurs in a much wider area as could have been directly affected by the initial impact.

The image suggests that the "routine maintenance" for Earth would involve using the Hawaii hotspot (possibly via its most active volcano, Kilauea), as the point to insert the high-pressure gas, causing volcanoes to erupt in Iceland, the Aleutian Islands or the Kamchatka Peninsula, the Andes, and elsewhere; the two geographically-indeterminate plumes may represent Italy and Indonesia.

The title text mentions using the can upside-down, and this freezing solid the magma chambers. Canned "air" normally uses some kind of refrigerant, as their low vapour pressures allow for safe storage in liquid form. When the can is reversed, part of the liquid refrigerant escapes through the nozzle, and when it reaches the outside, the sudden reduction in pressure causes it to vaporize. This state change is accompanied by it stealing heat from the surroundings, significantly dropping the temperature. Under 'normal' use, the main temperature change (or reallotment of heat energy) is concentrated in the can with the cooling of the spray a secondary effect (being the canister gas/ex-propellant that has been cooled by the pressure-producing liquid 'boiling off' within the can), making the body of the can itself cool to the touch. By directly releasing the 'pre-evaporated' liquid, it will then boil off upon the external target of the spray and instead take a majority of its heat from whatever the narrow stream of pre-evaporate lands on, which is often a much smaller body than the can itself and thus experiences a notably more extreme temperature drop for the (essentially) identical total redistribution of heat energy. Spraying canned "air" in reverse is a party trick used to very quickly cool beverages, being able to bring them down from room temperature to nice cold in seconds, if performed correctly.

Transcript

This transcript is incomplete. Please help editing it! Thanks.

[The nozzle of a "Dust-Off" gas duster can is pointing into a hole on the Earth's surface in the Pacific Ocean around where Hawaii is located, and its trigger is pressed as an arrow indicates, resulting in dust clouds being released from five visible spots of the Earth. These eruptions can be seen in the Aleutian Islands or Kamchatka Peninsula, Iceland, the Andes, and two further in the eastern hemisphere on the other side of the Earth.]

[Caption below the panel:]

I know routine maintenance is important, but I hate how we all have to take shelter for 48 hours every year while they flush out the Earth's magma system for cleaning.

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Discussion

Ooooh, if this were only true... All the "Nobody tells me what to do" stubborn people would have died out years ago, and Covid would have been a LOT shorter! :) Added an initial explanation, all I found here was a basic transcript.

The vent off of Alaska is poking out, is there a volcano around there? Feels a little north to be Mount Fuji, but I have a suspicion most if not all are supposed to be actually volcanos... NiceGuy1 (talk) 04:12, 29 June 2024 (UTC)

Russia's Kamchatka Peninsula (the long "teardrop" hanging below the Siberian Peninsula) is very volcanically active. The others look like reasonable places to expect volcanoes - I've added a couple of lines. 172.68.64.207 05:25, 29 June 2024 (UTC)

Is the image SUPPOSED to be that tiny? It's not even 800 pixels! 141.101.109.166 05:46, 29 June 2024 (UTC)

Should the direction of up/down actually being away/towards the planet due to gravity and not the panel's up/down direction be addressed in the explanation? 172.71.31.150 13:34, 29 June 2024 (UTC)

The current explanation says that cans of compressed air are pressurized with a propellant gas. This seems unlikely to me, but it's not impossible... it's just that I'd expect a can of compressed air to be only that, without needing a propellant. What I'm seeing in a quick search on-line supports that. Do cans of air/propellant exist? BunsenH (talk) 16:09, 1 July 2024 (UTC)

It would be impractical to have just normal air, compressed. A typical spray can cannot hold the pressures needed to have significant (i.e. useful) amounts of compressed 'normal air' (still gas, but a lot of it... think, basically, of a cylinder of Nitrogen gas, because air is mostly that anyway). And 'typical air' doesn't readily liquify (the way of concentrating it without necessarily extreme pressure), not without applying/maintaining extremely low temperatures.

On the whole, regular mostly nitrogen plus significant oxygen plus some CO₂ and a host of trace gases would never practically fit in a handy spray can such as you could hold (and, probably, afford to use) as an alternative to any pumped compressed (or fan-blown) air in 'trivial' tasks such as just blowing a tiny bit of dust off of a mobo.

What the 'air' is, in such cans, is probably (mostly) whatever handy liquid-adjacent gas is usable as an actual propellant. As you only need the 'general gas', you might as well just put propellant in the thing (one that works well) and nothing else. (Unlike things like air-fresheners/bug-spray, which need the 'freshener'/insecticide as well. There's no advantage to reducing the propellant to fit 'air' in, which would soon be so diluted by gasified propellant that you'd basically have no 'air' left).

The listed possible gases in a gas duster are the likes of butane, propane, 1,1-difluoroethane, 1,1,1-trifluoroethane or 1,1,1,2-tetrafluoroethane, with the first two being flammable (so would be problematic in some circumstances) and the rest being more inert but still not being 'safe' if improperly used. Or abused.

I don't actually have a can, at hand, or I'd check its stated ingredients (and warnings). I probably am more likely to (carefully) blow dust away with my own breath, or get the vacuum cleaner out with a suitable attachment. In fact, I've used very few, ever, though I probably first did back in the early '80s (which means it might even have been basically an example (or mix) of a CFC gas, before the problems with that became 'a thing'), as part of a cleaning kit sold to service my BBC Micro. 172.70.86.35 17:44, 1 July 2024 (UTC)

The popular 'can dusters' are NOT compressed air (oxygen/nitrogen mix) despite the label -- air cannot stay liquid at room temperature, it is high above the critical points of both nitrogen and oxygen. Many of such dusters don't display ingredients, but have a prominent FLAMMABLE warning sign! It is a propane/butane mix most of the time, maybe some CFCs in old ones. You could make a flame torch out of them! so be careful, turn off your device and provide very good ventilation. Best use it outdoors or on a patio, etc. -- 172.68.159.20 18:04, 1 July 2024 (UTC)