[oh_sigh]

Have you done the math on this? I have a feeling you're relying on a gut instinct and didn't actually simulate it. From my simulation, this new gadget will simply shift lines from the paper towel dispenser/on the wall air dryer to the sink itself. It will not at all reduce the efficiency of the bathroom, infact it will increase it

[ChuckMcM]

I chuckled because this same exchanged happened in my head when I read the article, my first thought was "Oh great, everyone stuck at the sink" followed by "Would they stay at the sink in practice?"

I've seen a couple of air-blade installations, and in those they have slowed things down because paper towel dispensers allow you to take a towel, step back, and dry your hands while another person gets a towel. Rolling towels (ones where the towel is on a continuous loop) have the same issue of one user at a time.

On the other hand ever every faucet was also a drying station you've basically upped the number of drying stations tremendously and that is a win for speed.

Side benefits of keeping water off the sink/floor are good.

I wonder if we'll ever see anyone taking this to the extreme of stalls with only water and air tools for washing up (Japanese style toilets for wiping, local air-taps for your hands).

[oh_sigh]

> I've seen a couple of air-blade installations, and in those they have slowed things down because paper towel dispensers allow you to take a towel, step back, and dry your hands while another person gets a towel.

I largely agree with your points, but I wanted to point out that most modern bathrooms(and certainly not bathrooms that may have this device deployed) don't have paper towel dispensers. So it isn't a question of paper towels vs this technology, but this technology vs the hot air fan, or the dyson air blade, or other similar non-dead-tree tech

[jpatokal]

Japanese bathrooms still have toilet paper dispensers, because even those probing little robot arm squirters can only clean so much. The usual protocol is thus to wipe with paper before you enjoy squirty fun time.

[stcredzero]

> Side benefits of keeping water off the sink/floor are good.

What's keeping the air from blowing droplets of water from the sink to my shirt or face?

[ChuckMcM]

Well if you've used one of their airblade systems you can see that they have a 'down shoot' sort of effect. I've never seen an air-tap so I don't know if they achieve the same result but I suspect that the water uses the same path as the air, and so blowing toward the sink would make the most sense. In that case a poor basin design could get you into trouble with water bouncing back I suppose.

[dhughes]

An AirBlade bidet, ouch!

[moe]

I don't know about your simulation, but over here in the real world it doesn't work that way.

Many people don't dry their hands at all in a public bath room (that's what god invented jazz hands[1] for).

By combining faucet and dryer you force these people into the same bottleneck as the hand-dryer users.

[1] http://www.youtube.com/watch?v=xuPSIbABYVU

[oh_sigh]

> I don't know about your simulation, but over here in the real world it doesn't work that way.

Wow, great point. You're obviously unbiased! You don't even know the details of the simulation, but you're confident that you really know what's up based on your presence in "the real world".

> Many people don't dry their hands at all in a public bath room

Yes, but they still wash their hands. Many people don't dry their hands because they have to use the hot air blowers, which they know are ineffective. If they see an effective device, some members of that group will choose to use it instead of jazz handing. But even discounting those people, the wash + dry combination still works out better for most cases I can devise. The only universe I have come up with where wash and then dry else where is better than washing and drying at the same station is if there are an equal number of paper towel dispensers as there are to sinks, which has never happened in a bathroom where the number of sinks > 2, as far as I know.

> By combining faucet and dryer you force these people into the same bottleneck as the hand-dryer users.

I wasn't arguing for optimizing any one special interest groups time spent in the bathroom, I was optimizing for the total network throughput of the bathroom.

[moe]

I was optimizing for the total network throughput of the bathroom.

But you didn't. You have serialized access to two resources that were previously independent.

Since a significant portion of users need only one of the two resources you have created a new point of contention. For access to the faucet not only do I have to wait for people washing their hands, now I also have to wait for people drying their hands.

[petsos]

Yes but one of the resources (the dryer) has increased significantly too. And since we are both using the word "significant" instead of any real numbers we can prove either point.

[stcredzero]

I call BS. It should only take 6-8 seconds for someone to grab 2 pieces of paper towel once they're at the dispenser. That means 2 towel dispensers should be a match for 5 sinks.

[incongruity]

It's actually worse because you take what were 2 parallel operations (washing your hands and drying them) and make them two serial operations, not able to be run in parallel.

[oh_sigh]

Yes, it does upset the balance slightly for people who want to wash their hands, but not dry them, and for people who want to dry their hands, but not get them wet.

Those are the only scenarios where your argument holds, however.

[incongruity]

No, not at all.

Simply put, you are moving from 2 independent operations to 2 mutually exclusive operations – meaning that 1 sink (in the Dyson case) can only service 1 user at a time vs 1 sink+1 dryer/towel dispenser which can, at a minimum, service 2 users at once (there's actually a much bigger set of time/path calculations that could go in to this, but the simple case is enough to make it clear that your thinking is confused on this.)