Lasers 101 with LaserEd: Laser safety and laser uses

Laser safety - Edwin Kroon - Lasers 101

Welcome to #LaserEd. My name is Ed, and I work with lasers.

I’ll be laser-educating for The Metal Magazine and I hope it results in more metal parts being lasered!

I have a different, often refreshing view on the world thanks to my education in Animal Sciences. If you’re wondering how that could improve the metal industry, I recommend that you listen to podcast 9 from The Metal Guys Talk Business, where I talk in detail about my background, and how I got involved with the metal sector.

Click here to listen to the podcast episode

Every article will start with essential knowledge about lasers and end with directly applicable and beneficial examples. Sprinkled with some interesting, fun facts about lasers, and topped off with links towards more information.

Safety and security

Lasers are grouped into safety classes and these are based
on the damage they can do to you. Class 1 is regarded as
safe, class 4 very unsafe.

This system worked well until someone realised that a laser beam that doesn’t damage your skin could still blind you. Permanently.

As a result, they added the letter ‘M’ classification to several classes to indicate that it is safe, unless you’re using Magnifying optics (e.g. class 1, class 1M, class 2, class 2M).

My rule of thumb for keeping your eyesight and generally succeeding at life is: don’t look directly into any type of laser.

Although cat-toys (class 1) and laser pointers (class 2) aren’t dangerous, looking at them can still be very unpleasant because the light overexposes your eye and you’ll probably see a weird spot distorting your vision.

CD/DVD-players are class 3B and the real fun begins in
class 4: industrial lasers. These can burn skin or
permanently damage an eye from direct, diffuse or
indirect beam viewing (i.e. when you look into the lens (direct)
or look at the surface that is being lasered (indirect)).

These classes of lasers must be equipped with a key switch and a safety lock for obvious reasons. But this is the tricky part. Anyone who has put a red sock in the laundry with the white wash by mistake knows what a <insert expletive here> a safety lock can be. And now imagine that your laundry starts to burn. As the classification neatly says, class 4’s can “ignite combustible materials”. Combine that with a proper airflow thanks to the fume extraction and you’re starting more fires than The Prodigy.

Read the UK Government’s laser safety advice, which gives more information about the different classes of lasers, by clicking here:

You can also read more about laser safety on everyone’s favourite fact-checking site:

If your adrenaline kicks in, you’ll probably grab the door of the laser machine to open it, exposing yourself to the laser in the process of trying to get to the flames. I did say in a previous paragraph that even an indirect laser beam can be harmful.

The open tabletop lasers that are cheaply bought from questionable online marketplaces do not comply with any of the laser safety regulations. The other laser, with the door that you just ripped open, did comply. But anyone with a bit of common sense will see that the intent of the law is safety. For hands, for eyes, for others around you. Do not swap one dangerous situation for another potentially hazardous one.

The scariest industrial laser I’ve seen had no safety door, and had the emergency cut-off button placed behind the operating area of the laser. This meant that you had to reach through the laser beam in case of an emergency!

Safest laser ever?
Laser not handy for lefties

Just a couple of examples of the extremely dangerous lasers available

From a biological point of view, we all have an idea what adrenaline does, but in short in a stressful emergency situation it shuts down the slower ‘thinking’ part of the brain and activates ancient behaviour that we now call the Fight, Flight or Freeze response. Everybody reacts differently, but when lasers are involved it’s mainly the Fight responders that we need to look out for: with enough adrenaline, everybody turns into Superman. And I’m not referring to his ability to shoot lasers from his eyes – how many times must I tell you: keep the lasers away from your eyes!

We train operatives to take a step back under such circumstances, preventing them from reacting without thinking and opening the safety door.

Even better would be to use a door-sensor linked to the kill switch, which immediately cuts the power to the laser if the door is opened. Your engraving might be ruined, but at least you, the laser and the building around you are OK, and you can tackle any emergency situation without worrying about whether you’ll lose your eyesight.

This door-sensor option would only fail if you could open the door faster than the speed of light – 300,000 km/s – and some of the laser beam was able to escape before the power was cut.

That’s why all of the lasers we produce at Lion Lasers use a door-sensor linked to the kill switch. The simplest solutions are often the best.

Use cases for industrial lasers

Let’s consider an industrial tool rental company as an example. The company hires out tools such as wrenches and spanners and screwdrivers, and loses thousands of pounds’ worth of tools each month.

The first idea that they had was to paint the tools in bright colours, so that they couldn’t be mistaken as belonging to anyone else. They could paint the tools in different colours each year, so that old and new tools could be differentiated. But the cheap paint lasted around one rental period and flakes of paint started to be left everywhere. Industrial tools can take a beating, but cheap paint can’t. They painted the tools with more expensive paint, which lasted twice as long, but still now only two rental periods and not worth the effort or expense.

Their next idea was to add barcode or QR code stickers to the tools, so that they could be tracked and located. This was cheaper than painting all of the tools and meant that the tools could be traced on a computer system. Excellent! But over time, the stickers started to peel and fade and became more difficult to scan, so customers had to wait longer at the cash desk, employees became impatient, and tools ended up being rented out without being scanned. Lots of time and money spent on software and scanners and training, and still no satisfactory solution.

So, the best and final solution, of course, was found by using lasers!

The first part of the problem – identifying who the tool belonged to – was solved easily, by laser engraving the company’s name on to the tool.

A barcode can be scanned easily and reliably, even if partly obscured, and if the barcode fails to scan there is always a number written underneath that the employee could type in manually. A custom barcode of 7 digits allowed for 10 million different codes, which was plenty to account for all of their inventory. Rather than add these barcodes as stickers, they were laser engraved into the tools to remain there permanently. For ultimate readability, the metal was laser engraved to turn whiter in colour, and for additional durability a layer of varnish was added.

As a result of this laser engraving process, the number of unscanned tools was reduced to zero, and being able to trace all of the tools on the computer software reduced the number of tool-gnomes by 90%.

There are many other use cases for industrial lasers, and I’ll discuss some more of those in my next article.

You can connect with Edwin Kroon on LinkedIn, or find out more about Lion Lasers by visiting their website:

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