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To bolster its environmental kudos (and pressumably to
costs), the organisation at which I work has recently
of the two paper towel dispensers in each washroom with a
electric, wall-mounted hand dryer. They did a short trial
products in a couple of washrooms before
rolling out the winner, a slick, stainless Dyson slimline
the rest of the building.
Now these dryers work well enough, but they're not as
as the paper towels they replace as they take longer and
one to contort one's hands and wiggle them about to get
sufficient coverage. Plus they are incredibly noisy to the
where I feel people are inhibited in using them. Not to
the occasional scares from the press and from the office
grapevine that, by drawing air from the washroom, these
are spraying fine faecal matter onto the hands of those
them, effectively undoing the prior hand washing efforts.
So, naturally, I was pondering how these devices could be
improved, and then my elementary science knowledge
and blessed me with a eureka moment: what if rather than
blowing the water from my hands it could be boiled off
Would that not be a more triumphant way to dispose of the
excess moisture from one's digits than the glorified fans
these hipster design bureaus are peddling?
A quick visit to Google Images later and I had the chart I
plotting the boiling point of water against pressure.
one would not want one's hands to be boiled dry at 100°C,
that could cause some discomfort, so our newfangled hand
would have to lower the pressure somewhat, for, as we
know, the boiling point of water descends as does the
From my chart I could see that the pressure would need to
fairly low before we would get into the realm of tolerable
temperatures, so the dryer would need to create something
to a vacuum.
So I envisage a container mounted upon the wall, a lot like
conventional, electric dryer, with two holes upon the front
which one would insert each hand. A silicone rubber
would then tighten about the wrists to create a near air-
A couple of small jet engines would then spring to life,
the air from the chamber to lower the internal pressure
upon the ambient temperature, such that the moisture
hands would reach boiling point. This would mean that on
warmer days it would be possible to create a marginally
The user of the device would then wait a few seconds whilst
water gently boiled off of their hands, the sphincters would
almost certainly release their grip from around the user's
and they would be free to walk happily from the washroom
bone-dry hands and only minor bleeding from the
(If the jets prove to be too noisy then the chamber could be
to expand, like a syringe, by pneumatic jack thus lowering
pressure by increasing the chamber volume.)
Lead hand dryer
[bs0u0155, Jan 04 2019]
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||//A silicone rubber sphincter would then tighten...// - I can think of no other alternative uses these devices might be put to by mischievous or adventurous individuals in the average public toilets.
Another approach to this problem might be to have the entire room at a reduced pressure. Users would have to hold their breath, but this is a fairly common requirement already in some public toilets. A side effect might be that a reduced ambient air pressure might assist the exertions of those with constipation.
||I did actually have the idea of a shower cubicle sized box
that could be depressurised for full body drying but that
scene from Total Recall with Arnie's bulging eyes still
||... as indeed it does everyone who has ever seen that movie.
||We like this idea, and award it a vacuum-dessicated croissant. The idea of employing tiny gas turbines, while technicaly impractical, is particularly praiseworthy. [+]
||We also commend the designer for // only minor bleeding from the fingertips // which shows a nicely robust and uncompromising approach to product safety, and the health and wellbeing of users.
||I think touch is the crux here and those cuffs might have more than the natural amount .
||//the organisation at which I work// Hey! One of us got a
job!! Well done that Halfbaker.
||Part of the problem could be solved by replacing the water
taps in washrooms with ethanol taps. Ethanol has the
advantage of sterilizing hands more effectively than soap and
water, so there'd be a saving on soap for starters. And then,
when it comes time to dry, ethanol's lower boiling point would
come into play. Flammability issues would need addressing,
but I can't see that being much of an issue.
||The ethanol could be filtered and recycled; but we forsee a potential problem of users abstracting the liquid for use as vehicle fuel.
||//we forsee a potential problem of users abstracting the
liquid for use as vehicle fuel.//
||Use a reasonable gin or scotch. Most vehicles won't run on
that without a lot of tedious re-tuning.
||Actually, I think I've got it. Silver/Copper are both pretty
potent antimicrobial materials. Hot things are good at
flashing off a little water to steam, so why not have a bath
of molten silver by the door, a quick dip and shake and your
hands should be dry and sanitized. Mythbusters showed it
was perfectly safe using lead I think, but lead isn't in the
same league as silver/copper when it comes to antibacterial
||Why not use a liquid with a strong affinity for water - concentrated sulphuric acid, for example ?
||//liquid with a strong affinity for water//
||ah, liquid sodium then. Or potassium for those watching
their blood pressure.
||Given that its freezing point is -12C, NaK is the obvious candidate material in this application.
||Since it's pyrophoric, it might be advisable to fill the room with an inert gas; Argon would be best.
||If a prankster were to tamper with the seal mechanism it would make for some wicked arm hickeys.
||Yes, but what sort of sick, cruel, reckless and sociopathic person could even contemplate such a wicked, spiteful act of twisted and irresponsible vandalism ?
||This idea sucks rather than blows. I like it.
||//what sort of sick, cruel, reckless and sociopathic person could even contemplate//
||Yes, well, you don't get to survive them without learning how they think.
||Hand dryer is only for hands. Do not place other
body parts in the hand dryer.
||Oh, indeed. Imagine thrusting your damp appendages into the dryer, wanting nothing more than the rapid and hygenic removal of surplus water, and finding that a previous user has deposited a disarticulated foot in the device ...