Safety Guidelines for would-be builders of projectors

[mccarrot]

The big question on the other side is: How much power (density) is required to get a good visible beam? And I'm not talking free air, but not clouds of fog either. More like a hazer running during the gig.
.

1mW/person is a good guideline, for green only you can do with less power with a RGB its better to have more power.

so for a event with 500 people you can use a 500mW projector.

this is WITH audiance scanning, I think with overhead only (US shows) you need more power.

[slicklasers]

The first is for anyone who wants to know the requirements for ALL lasers by the CDRH. It doesn't matter what kind of laser, diode, gas, dpss, opsl, yag, co2 or if you can get a tube of toothpaste to lase, you get the point, ALL LASERS.

The second is for any Laser System, A Laser system is any sort of system that uses a laser of any kind.

The third has the requirements for a Laser Demonstration, i.e. a laser show.

[dsli_jon]

Hey Kats -

1) Only solid state/dpss projectors

Agreed. And like Dan said, no 'support' for pulsed / hi-power systems - those can be 'dealt-with' on a case-by-case basis (...let's see your 'papers' first, son, then we'll talk"...that's the way (IMO) I'd prefer to see things handled with those lasers - you qualify to own / operate first (training) THEN we talk about getting you info on how to make a projector... but that's just me, I guess...)

And ions, as-well (mostly, because of the HV involved) ...it's pretty 'nerve-wracking' to read posts where someone is trying to 'talk someone thru' working on a lit tube or psu - and then the thread 'goes silent' for a week... which is really worrysome, from a 'liability' standpoint... again, ions, too, I think would be best-dealt with on a case-by-case basis, here... Especially since *most* 'newbies' are not coming-in, here, trying to go 3Ø and water, out of the gate...

But then, is there a 'question of liability' if those topics are NOT covered? Perhaps, just a few 'lines' / warning statements, and links to external / 'someone elses'-liability' info-linx? thoughts?

2) No audience scanning

yeah, trouble there is then you get into either publishing 'trade secrets' (technology / IP, like, PASS / beam-brush, etc) which will get challenged, and/or the complexities / minutia over HOW 'MPE' is defined / standards, here, vs EU, etc... Dunno - best to have just 'external links', here, too? But then, again - if you DON'T publish complete info - liability, for not?

3) Only projectors capable of an output UNDER class IV (requires further discussion)

well...

The under class IV thing effectively rules out a LOT of the UK hobbiest market...

In fact looking at what most people ask for help with here, it tends to be solidly into class IV.

Yep, certainly seems like MANY / most folks here are working with Class IV / near-Class IV lasers, let-alone projectors...

Given criteria like these, I think we might be able to reasonably assemble a set of construction, operation, and paperwork filing guidelines that, being within the limitations listed, would cover 99% of what most hobbyists want to do.

And perhaps that is the 'key', to where to start / what the 'boundaries', for this should-be - stick to trying to build a set of guidelines for hobbiest-level folks (NOT an 'anti-competition' statement... ) mostly due to 'liability-issues'... thoughts?

We need to restrict to the projector itself as well, so as to avoid 'venue' issues (About which you can write whole books), and as I see it there are 3 major areas that need attention:

1) Radiation safety.
2) Electrical safety.
3) Rigging and structural safety.

Agreed, but your #3, does bring up a thought - what, for example, if someone does 'follow the guidance' on a projector, here, but then goes and puts up a scrim, but NOT a fire-retardant-one - and there's an 'incident' at the gig? Is there liability, cause 'we' DIDN'T tell him?...Might be best to make sure ANY 'advice' / how-to, IS, in-fact, complete and broad, again, within the 'boundaries' (no pulsed-laser info, etc)...

But I understand what you are saying - if we 'open' the 'Venue' book, it could get HUGE (scrims / rigging; how to safely route power cords; tripods vs scaffolds vs truss; visual-control of the venue; mirrors/safties; ad infinitum...) - thoughts?

cya
j

[DMills]

I dont think we can touch the issues of venue rigging at all, leave that to Chris Higgs, Harry Donovan, Bill Sapis and Glerum, it can be specialist (And no, reading a book will not give you the skills, but may give you something to think about).

What I really meant my rigging was more in the line of fitting sufficiently robust points to secure secondary suspension cables and making sure that when it drops half a meter onto the end of that secondary suspension, nothing falls off (The projector does not have to survive, but nothing should fall ouside the case and it should not leak light).

My thoughs would be that if we do this thing (and I would like someone more experienced to do the radiation hazzard section, I can hum the tune, but there are others here far better at writing that stuff), then we should narrow the scope as far as possible, and document explicity both that this is written by some random guys on the internet and that it does not cover all risks.

Regards, Dan.

[Stoney3K]

What I really meant my rigging was more in the line of fitting sufficiently robust points to secure secondary suspension cables and making sure that when it drops half a meter onto the end of that secondary suspension, nothing falls off (The projector does not have to survive, but nothing should fall ouside the case and it should not leak light).

Tip here: Use a 'dead man switch' line like they use on jet ski's here. Make a short piece of leash or lanyard attached to a pin, which needs to be in place for the projector to operate. If the unit should fall, the pin will get pulled out, and immediately disengage the power to all of the lasers.

Of course, the line needs to be shorter than the secondary safety cable, and preferrably attached to the support structure at the same point.

[dsli_jon]

Hey Stoney -

Tip here: Use a 'dead man switch' line...

Good thinking, but you might also not want the cooling-system to your lasers (even if all SS) to simply up and die - might be 'better' to simply tie the 'trip' into the interlock circuit - very commonly-done in a million-different ways (ie: door-switch in a laser-lab, etc, etc) so plenty of connector / switch-options, and then, your output is killed - but your diodes / PSUs keep being cooled, especially if they've been on full-bore awhile...

...and certainly, if your rig falls far-enough to-where a power-cord would also get pulled-out (like, an IEC vs a hard-wired line...) - you're probably talking about a situation where laser-output would be the 'lesser-concern' (like if a whole truss-section came loose, or something... ) - but good suggestion, either-way..

cheers..
j

[drlava]

Thank you all for chiming in and moving forward with this. Those are great suggestions so far. I agree we may not want to limit it to 500mW projectors, it was just an option to simplify the task.

So far the criteria stands:

1) Only solid state/dpss projectors
2) No audience scanning
3) No unterminated beams
4) Only projectors capable of an output UNDER some limit.. 5W? The safety burden should determine this in some way
5) CW only, no Q switching/cavity dumping.
6) Directly air cooled (No water loops).

Other ideas:
7) Single Phase 120/220 (to simplify wiring section)
8) Indoors only?


So the sections listed so far:

1) Radiation safety.
  A) E.U.
    a) Indoors
    b) Outdoors with beam termination
  B) U.S.
    a) Indoors
    b) Outdoors with beam termination
  C) Interlocks (electrical safety inside the box)
2) Electrical safety (outside the box).
  A) E.U. with notes for lower voltage U.S. installations?
3) Rigging and structural safety. (should be the same across the board)
4) Projector variance
  A) U.S.
    a) requirements
    b) submission (howto)
  B) E.U
    a) ?

[dsli_jon]

hey DrL -

It might make more 'sense' to 'tie sections-in' to the Regs, since most of the stuff we 'do', is driven by them, anyway.. then, of course, follows 'common-sense' / experience-taught lessons / tips / tricks, etc... ie:

1) General Overview / Intro

a) Introduction / Discussion of 'Principles' / Whys / Importances of Safety
b) Acknowledgements / Contributors (quick reference for who to go-to for more 'explicit' info / details on a given-section - this can 'change' / update, as-need-be...)
c) Disclaimers (liability-reasons - 'this is ALL done 'at your own risk / liability', etc)

2) Regulations - what / why / where to access current info / Contacts

a) US
1) CDRH
2) State by State
b) EU
c) Canada
d) Home / University / School-Context (where/how any Regs are applicable, if-so)
e) Mobile (temporary) vs Install (permanent) considerations

3) Reg Compliance / Application Tips

a) US
1) CDRH
2) State by State
3) FAA
4) Fire Marshals, Cities, Theater Managers and other 'non-regulating', (but possibly 'gig-influencing') entities...
b) Canada
1) Dept of Justice (RED)
2) Transportation Canada (airspace)
c) EU
1) IEC
2) HPA, (country-by-country, here?...)
3) CAA, ...

4) Laser Safety

a) Classes
b) Measurement (audience-scanning excluded)
c) Protection Gear (goggles, etc)

5) Projector Safety

a) Construction (materials, rigging, etc)
b) Electrical Safety (inside)
c) Electronics Safety (needed? TBD)
c) Galvos and Optics (handling, heat-sinking, reflections, etc)
d) Other Components for Compliance (interlocks, shutters, indicator lamps) and Approved-parts Sources

6) Laser Projector Radiation Safety

a) Practical-Application of the Regs
1) Distances and 'Exceptions to the Rules'
2) Bounce Mirrors and Mirror Balls
3) Masking and Blocking - materials / sources
4) Attentuation Maps and Software-considerations
5) Cabling and Connectors
6) DMX and RF Cautions
b) Venue-considerations
1) Rigging Overview
2) Electrical / Cable-routing Safety
3) Scrims, Screens and Fire-Retardancy
c) Protective Gear
1) When necessary and Discussion
2) Sources

7) Venue and Show Production Considerations

a) Liability and Equipment Insurance
b) Client Education
c)

8) Emergency and Incident Management

a) Procedures for Reporting / Documentation
b) Reporting Forms
1) US
2) EU / UK
c) ???

9) Bibliography / Refs/Links

a) etc, etc...

---

Please feel free to re-order / add/subtract / correct / delete, etc (especially, Help from the EU-side! .... Let's see how far we can take this, Kats... Then we'll let it 'sit a few days and 'bake', and come back and see what needs to 'change', before 'filing up the shell'...

peace..
j

[mixedgas]

Sam refuses to discuss ANY aspect of laser shows in the FAQ other then a few blurbs on modulation and white light lasers and what a galvo is.

PL IS the proper venue for this.

I prefer, and have stated in the past, to draw the line at 300 mW for hobby/beginner hobby status. Much above that and errors/accidents can really start to grow. I just flashed back to a memory setting a venue wall on fire at a few watts CW from 70 feet. Be sure of your target is thus the first rule. Knowing how to test your target, ie the 20 minute exposure listed in the Laser Images old manuals, comes to mind as part of what needs to be included in this document. If your out there at more then 300-400 mW, there is a heck of a lot of extra stuff to factor in, like walls.

I'm in the middle of a super mega project at work and can not really contribute for the next few days.

Steve

[drlava]

Very nice! I think the perfect medium to do this in is a Google Wave or a Google Doc. A wave is like a word document, but it can be edited from many people at once, and all changes are tracked and can be 'played back.' I have a bunch of 'invites' to email to everyone who wants to be involved, because a long time ago I hoped something like this might happen and signed up. The end product would be more portable and better formatted than a wiki, and snapshots could be taken and posted here for review.

Right now might be a good time to start gathering contributor/reviewer volunteers, please PM me an email address, and I'll send an invite to the wave document.