A few years ago a first or second year engineering
student was showing off his wonderful homemade
Goggles using dyed theatrical gels. On the Youtube platform
and in several laser forums. He had never heard of or believed
In photo-bleaching. He just would not listen to reason.
He also had a wonderful video claiming that surgical gloves, double layered, were safe for handling charged flashlamp capacitors.
So he put his university logo and the NSF logo on his presentations. My email to his Department Chair and Dean read simply "Is this one of yours?", with links to the videos and the PDF presentations. I hope his parents enjoyed paying
for an extra semester of Engineering College.
This is a serious business. I have a tiny retinal burn. A fellow operator walked into the laser control booth , ignored my lockout tag, and booted the control system. A shutter opened for a brief fraction of a second, then a beam deflection arm moved as well. When the deflection arm moved, my right eye caught a brief reflection.
Fortunately for me, I had the system idling at 20 milliwatts instead of 20 Watts @ full power. 20 mW of blue at 488 nm works out to around 100 Kilowatts per cm^2 at the spot size on my retina out of that system.
My burn was minor compared to what could have happened.. Spending the next three days watching my brain recalibrate my eye to fill in the damage around the spot was terrifying. I'm lucky, the damage is on the edge of my peripheral vision and not on the optic nerve. I was "lucky".⁸
The procedure I was following was otherwise very, very, safe.
Today I would be using an alignment camera instead of a diffuse target for the task mentioned above. In 1989 that option was not easily available.
If my story does not scare the he'll out of you, it should
Every laser specialist I've ever spoken to, will tell you it's better to be dead then to lose an eye.
I've spent years studying laser safety. Yes, in the US, in theory you can buy anything you want that is not export controlled with the exception of five states that require various levels of licenses and training. Provided it is an approved device. In reality there are controls in place. DoD for example expects units to destroy any laser before disposal. Most universities will destroy a used laser, as will most corporations.
CDRH rule violations can get you a visit from ORA, the FDAs enforcement arm. I assure you their job is taken seriously.
However, the moment you turn the safety key on, damaging someone else's eyesight exposes you to drastic legal and civil
penalties.
I cringe every time I read a certain safety manual. It has a few paragraphs from a well trained technician describing the last thing he saw in his right eye was his eyeball filling with blood.
Don't screw around with what you do not understand.
Seriously, if your NODS device, if you really had one, is so insensitive that you need a IR laser illuminator at 1 watt to use it, something is very, very wrong. Not to mention the forward scatter off dust in the air will illuminate a path right back to your position at that power level.
BTW, LEDs have long ago reached the point where they are a hazard in some cases.
Also, removing a lockout tag that is not yours will get you fired, escorted off the the premises, a horrible reputation, and the union, if there is one, will not help you. In fact the union will kick you out and help management fire you.
Radiation safety is no joke with non-ionizing radiation.
Steve