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Mixing an invisible laser and a fire alarm made for a disastrous demo

Dark deeds are no way to close a deal

Who, Me? Happy New Year, gentle readers, and welcome once again to Who, Me? – The Reg's regular roundup of rapscallions and rascals committing tech atrocities and (sometimes) getting away with it. This week it's got a sci-fi twist because the disaster in question involves lasers.

The story comes to use from a reader we'll Regomize as "Buck" who trained as a physicist specializing in lasers. In the 1990s he landed a job in Germany, as an R&D engineer for a company that made the light-emitting devices.

On the occasion at the heart of our tale, Buck was preparing an ultraviolet (UV) laser prototype for a Japanese chipmaker that had sent staff all the way to Germany for a demonstration and "acceptance testing".

"For this acceptance test," Buck writes, "I had set up a large optical bench, roughly 3m x 2m, full of sensors, lenses, mirrors and all the stuff you need. In front of it was the new and shiny laser itself, 1m x 2m and 1.8m tall. Everything was quite impressive looking – a lot of optics, sensors, spectrometers, a lot of cables and PCs."

He tells us it was all "very technical, very scientific, very expensive."

At this point, dear reader, we must remind you that this was a UV laser and that the human eye cannot see the wavelengths such lasers employ.

Buck also pointed out that you don't want to go looking for a UV laser - they can do nasty things to the eyes.

So the trick is to use yellow-tinted safety goggles. Even then, of course, a UV laser is only barely visible as a spot of luminescence when it hits a mirror or lens. Buck mentioned that you could also test for the presence of the laser by putting a bit of paper in its path – "but only if you use low laser power so you don't incinerate the paper immediately."

This really sounds like fun that is in no way dangerous or risky.

In order to make those tiny spots of light easier to see, the demo needed to be run in near-complete darkness. The problem was that in this particular lab, the ceiling had two large windows, which formed part of the fire-safety system. In the event of a lab fire they would swing open and allow smoke to escape.

Great for safety, bad for darkness.

So a couple of Buck's colleagues climbed onto the roof and placed sheets of black plastic over the windows, weighted down with bricks. Already you can see the problem, can't you?

With the lab darkened and tinted goggles donned (making it even darker), Buck proceeded with the demo. The huge laser hummed to life and set about lasering while the customer reps checked it over.

Wanting to discuss something without having to shout over the sound of the laser, Buck and a colleague carefully backed away in the darkness until they found a wall.

Whereupon the colleague's elbow found the fire alarm.

Power was instantly cut, the laser wound down and, for a moment, there was silence in the darkness. Then there were loud sirens, red and yellow flashing lights and gas and water fire suppression systems. Quite the scene.

Then, as the water and gas stopped with a hiss, Buck became aware of a loud banging from above. The smoke release windows were struggling to fulfil their function. Trying and trying again to swing open and release the non-existent smoke from the lab.

Eventually they succeeded – flooding the lab with light, as well as rain water that had accumulated in the plastic sheets. The Japanese customer reps were found huddled under the test table, their years of earthquake training having kicked in the moment all hell broke loose.

This was not, Buck said, quite the "impress the client, close the deal, score a giant bonus" demo Buck hoped to deliver.

Thankfully most (not all) of the lab equipment survived the ordeal. Buck does not tell us whether the customers accepted their laser prototype or not, but we have to assume they were at least impressed with the fire safety system.

Speaking of which, the boss was not at all impressed with the plastic-sheet kludge. A few months later, the lab reopened with proper blinds, emergency lighting … and an illuminated fire alarm button.

Have you ever terrified a potential customer with a demo gone crazily wrong? Tell us all about it in an email to Who, Me? and we'll share your story – names changed to protect the innocent (ish), of course.

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