The semiotics of plumbing is a slightly unlikely topic, but having not long ago discussed the affordance of soap dispensing, I now turn to the tricky question of how to turn on a tap.

There follows a ludicrously detailed description of an utterly trivial process. If that prospect does not fill your heart with joy, move on now. But that level of absurdity is necessary really to understand what might be going on and how it might be made better. The connection with public strategy is superficially very tenuous, but the reason for thinking about trivial questions in this way is to help us spot the same issues in much more complicated and less transparent situations. It is easy to spot when a tap has been designed in a way which makes its use straightforward and which Boiling and chilled water tapmakes it easy to get the desired result. It is much less easy to spot when a service has those characteristics (though sadly all too easy to spot when it doesn’t).

This isn’t a wholly ordinary tap. Its function is to provide office workers close to boiling water to make hot drinks and chilled water to do the opposite, and the two levers are labeled accordingly. So it’s quite important not to turn the hot tap on with your fingers underneath it (the sink separately has a perfectly ordinary hot and cold tap if that’s what you want). Most people manage not to pour boiling water on themselves, and in fact I have never heard of anyone hurting themselves that way.

Nevertheless, mysterious notices started to appear a few months ago. They referred to a safety button which nobody had ever spotted, still less used, but which on close scrutiny could be found just above the spout. Odder still, this button had no discernible effect on anything. Perhaps not surprisingly, the act of pushing a button didn’t seem to make boiling hot water any less boiling hot. Such signs also act as another kind of warning – as Don Norman put it, “if it needs a sign, it’s badly designed”.

Please note when operating for Hot Water press the Safety button firstWeeks later, the tap just stopped working. Things do stop working from time to time. After a while, somebody comes to fix them, then they start working again. Only nobody came and it carried on not working.

One day I noticed that the broken hot tap was warm to the touch, in the way a tap can only be if hot water had recently run through it. So I tried it again, but it still didn’t work. At which point the penny finally and slowly dropped.

The safety button now did indeed have to be pressed first. And this is where the fun begins. Now you need one hand to press down the lever on the top, one hand to push in the button at the side, and one hand to hold the mug underneath. That’s significantly more hands than most of us actually have. And the inevitable soon happened: now the tap had been made safer, I spilt boiling water on my hand for the first time ever.

But it gets better still. The tap levers have two positions. Press them down, and they are spring loaded. But pull them up and there is a hands-free flow of water. So a hack presents itself: pull the lever up and nothing happens. Then press the safety button, and water flows.

So if you treat the tap as the safety cut off and the safety cut off as the the tap, it all gets much easier – and can easily be done one handed.

Which of our services only work well if they are subverted?


  1. I suspect the intended purpose of the “safety” button is *deliberately* to force you to use both hands to turn on the tap, thus ensuring they are safely away from the area about to be sprayed with boiling water. If you find the need for a third hand to hold the mug directly under the tap, it’s probably because it wasn’t designed to be mounted over a deep sink, just a little drip-catching grid set in the worktop. The designer expected you to place the cup on the grid, then apply both hands to the tap. Your Facilities department then subverted that by deciding to save a few quid not installing the whole system.

    Not that this takes anything away from your point – if anything, it adds to it by showing how we get into this kind of state.

  2. I remember these from a previous office. It is possible to use one-handed: using your left thumb, press the safety button, then you’ve got the rest of your left hand to use the lever. Can’t believe I’ve just left a comment about a tap. Must be a CS thing.

  3. This often is the case where services are designed solely around lockdown safety measures alone – – and at the exclusion of simple user testing. The problem with reinventing the wheel I guess.

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