Initiative to regulate xenon arc-illuminated projectors like laser projectors

[Leo Enticknap]

This from Cinionic.

In December, the International Electrotechnical Commission (IEC) updated its safety standards impacting many lamp-based projectors, bringing them in line with the pre-existing standards for laser-illuminated projectors.

Known as IEC/EN/UL 62368-1 Ed 2, the new standards replace IEC/EN/UL 60950-1 for safety and testing of electrotechnical equipment, and among other things require lamp projector manufacturers to give lamp projectors a risk rating. These ratings come with regulations around optical hazard distances and other safety measures that can impact the design and operation of your cinema.

All new cinema lamp projectors must now comply with these updated safety regulations, globally. Additionally, for operators in the European Economic Area (EEA), safety-related bodies now require that all lamp projectors, are retroactively recertified and have a Risk Group (RG) assigned.

But what do these changes mean in practice for cinemas and projectors, and why is now the perfect opportunity to adopt the freshest laser-illuminated technology?

Let’s jump in.

1. New rules mean more regulations for lamp projectors

The technical language can be confusing, but the new projection rules can be summarized in a single phrase: Risk Groups.

Like laser projectors, the majority of lamp projectors in cinema are Risk Group 3 (RG3), meaning they have to follow the same safety standards and rules.

Why does this matter?

• RG3 applies to most lamp-based cinema projectors. Because most new cinema projectors (both lamp and laser) are classified as Risk Group 3, any new installation (or replacement in the EEA) has to obey the new rules—with all the responsibilities that follow.
• The rules are very specific. Apart from training and protection booth requirements, the new regulations also cover safety distances, hazard zones, and separation heights for lamp projectors.
• Change is inevitable. Your equipment will eventually need to be changed—and obey the new regulations. However, the consistent standard for lamp and laser projectors makes the move to laser an obvious choice.

The rest of it is basically advertising copy, the gist of which is that if you now have to faff around with hazard zones and such even if you don't have a laser projector, you might as well get a laser projector.

I'm also not sure about the "new projectors must now comply" assertion. Presumably this is only true if a country's national and/or regionally devolved laws enshrine all IEC regulations: otherwise, each country's regulatory framework will have to choose whether or not to adopt these new regulations. Obviously, I'd like to know, in respect of the USA and California at least, if we're now going to have to do, retroactively, the laser safety risk assessments on all the existing xenon installations we look after.

[Mark Gulbrandsen]

Leo, I;m surprised CA hasn't taxed Laser Projectors yet. They tax every thing else....

[Steve Guttag]

There was the absurdity that what was safe for a xenon projector was deemed not safe for a laser based projector...the only reason, in the USA, for this was that the FDA regulates all Laser based light sources. Xenon evolved on its own path. Furthermore, the vast majority of xenon based lamps placed them in inherently safer places (projection booths way above people's heads). Sure, there are some venues where this isn't the case but those are in the minority. "Stadium Seating" altered things a bit by raising the elevation of the typical patron up closer to the projector.

I, personally, think the regulations are a bit harsh already. I'll use a current project I'm working on now (in fact, just delivered the digital projector and pedestal, with riser).

Screen Shot 2021-03-16 at 7.24.32 AM.png
For the digital "laser" projector, with the lumen capability and lens type, combined with the auditorium risers versus projection angle, the last row is the only one in our Hazard Distance of concern. We had to put a 2.5-foot riser on the normal pedestal for the digital projector. The ceiling of auditorium had to be "bent" up to allow for the port and projection beam.

Now, for the film projectors, we did it the traditional way. We wanted to ensure that people walking across the last row wouldn't have their heads bobbing into the picture. We didn't protect up to 2.5m. Just just protected to 6.5' (and sometimes only protect up to 6-feet). This resulted in needing 9" risers for a typical film projector:

Screen Shot 2021-03-16 at 7.24.59 AM.png


Note too, from a safety stand point, there is a bit more protection since ones eyes are a bit lower (for safety, we aren't as concerned about getting contacted by the light so much as someone inadvertently looking back into the projection beam).

This, in my opinion is a completely safe system. For 99% of patrons (how many people, as a percentage, are over 6.5-feet?) they won't interfere with the image for other guests and there is no chance of accidentally glancing back into the projection beam unless you are in a very rare category of person...the same type of person that has to duck when they go through doors. Pushing the film projectors heigher may have meant raising the ceiling in the projection booth, which this drawing doesn't sho all of the various structure details that would have prevented it from happening easily or with reasonable cost.

Many drive-in theatres will have issues as they project upwards and many booths are built on the ground floor (often behind the concession area). Those that are built on the second floor (if any exists) shouldn't have an issue.

I also think it is way late in xenon's life to be worried about changing the rules of designing for it. Just how many people (again, as a percentage) have been injured due to inadvertently looking back into a xenon projection beam, at close distance? One does not need great prediction skills to see that xenon is nearing the end of the line. The current crop of laser based projectors have narrowed the gap on xenon in cost such that it can been cheaper to put in RGB laser on day-1 than an equivalent xenon based projector (compare pricing of an SP4K-25C to a DP4K-25C, for instance and the same holds true on down the line on the S4 projectors to their lamp based equivalents). And with laser, you don't need exhaust, your electric bill drops (significantly) and you get rid of, at least, one maintenance task with it's consumable part, the lamp itself. Sure the laser(s) may need to be changed but not near the frequency of lamps. Unless you are in a critical color grading facility, I'm not sure what the case is for putting in xenon based projectors anymore. All three of the OEMs have laser based projectors that are in cost competitiveness with their xenon projectors though NEC has, strangely, stuck by laser-phosphor, which introduces an expensive consumable (the phosphor wheel/motor) and has its own color issues. I guess that pesky green laser is just too expensive for them. However, NEC does have a projector where they have made the light source, as an assembly a service part that can be recycled so one need not do that work in the field.

[Marcel Birgelen]

More rules and regulations, that's exactly what an industry in dire straits needs right now...

For all kinds of reasons other than getting the best presentation out of your ticket, this last row in the auditorium seems to be the most popular one.

Given the rules for laser projectors around here, as far as I can understand, you also need to account for people that stand on the seats, but not for idiots that climb onto the headrest...

[Mark Gulbrandsen]

Steve, Drive Ins may have to build an entirely new elevated booth to be able to comply. None of the DI's I service could ever comply...

[Steve Guttag]

The height requirement for lasers varies around the world. A common theme is that if the seating is fixed, the requirement is lower (say 2m) versus non-permanent where the requirement may be 3m. The thought is that what if a child is being "carried" by sitting on a parent's shoulders? While this could happen at an outdoor screening, it is FAR less likely when exiting a commercial movie theatre.

[Marcel Birgelen]

I guess some cinemas will end up ripping out some seats and blocking off the area around the booth in order to comply.

Steve, Drive Ins may have to build an entirely new elevated booth to be able to comply. None of the DI's I service could ever comply...

Many Drive Ins should be able to comply by fencing off a bit in front of the projection window. In general, you only need to reasonably block the area where the light intensity is deemed to be hazardous to human eyesight with even minimal exposure. You need to block off such an area that the underside of the beam reaches the 2m-3m, whatever the local law says clearance in all possible lens configurations*. I guess that for most DIs this is a problem they can overcome and it will be cheaper than raising the booth an entire floor.

* Apparently, taping off your window in such way that the beam can't escape a set profile is sufficient, even if some possible lens configurations could overshoot this area, at least to local regulations for laser light sources.

[Mark Gulbrandsen]

I guess some cinemas will end up ripping out some seats and blocking off the area around the booth in order to comply.



Many Drive Ins should be able to comply by fencing off a bit in front of the projection window. In general, you only need to reasonably block the area where the light intensity is deemed to be hazardous to human eyesight with even minimal exposure. You need to block off such an area that the underside of the beam reaches the 2m-3m, whatever the local law says clearance in all possible lens configurations*. I guess that for most DIs this is a problem they can overcome and it will be cheaper than raising the booth an entire floor.

* Apparently, taping off your window in such way that the beam can't escape a set profile is sufficient, even if some possible lens configurations could overshoot this area, at least to local regulations for laser light sources.

It all depends on if they are gonna take into account the folks sitting in lawn chairs in the back of their pick up trucks or not. I believe the areas in front of the booths I service are fenced off. I know one is slightly below ground though.... But those conversions are a ways off anyway.

[Frank Cox]

Can you tell me a little more about this? It's all news to me.

I gather that if I was to get a laser projector at some point there's a minimum height that the lens has to be from the (floor? seat backs? head heights?) in the back row (only?)

Is there a minimum height at the front of the auditorium too? In my theatre, if tall people stand up in the front rows they can cast a shadow on the screen. Would this mean that a laser projector wouldn't be allowed here or ...?

[Steve Guttag]

Frank, you'd have to check with the laws of your Country as it varies. In the USA, it is the Food and Drug Administration (strange as that sounds).

There will be a minimum height that the projection beam must be above, again, in the US, it is 2.5m but that is NOT the same everywhere. How far in front of the lens you have to protect for this is dependent on the maximum lumen rating of the projector AND the worst case throw ratio of the lens you are using (how intense can you make that bright beam of light though you probably could get away with using the actual worst case throw ratio that you are using). Note too, if your projection beam does violate the height requirement, not only do you have to block off those seats (put up barriers to prevent crossing into the restriction zone), you have to protect 1m, laterally beyond where the beam is.

Even in the booth, you have to also consider reflected light off the port and not catching someone's eye as they walk the booth.

Each manufacturer has to provide what the hazard distance is based on this information.

Let's say you need 15,000 lumens to light your screen. If your lens has a throw ratio of 1.4 - 2.05, your Hazard Distance is about 1.75m from the lens. So that projection beam has to be, in the US, 2.5 meters above anyone closer than 1.75m to the projection lens. If, on the other hand your lens has a throw ratio of 2.4 - 3.9, with that same projector your Hazard distance just move out to nearly 4m. That said, if you are on a longer lens, odd are the image size at 4m is also comparably smaller and thus shouldn't be too much of a burden, unless the slope of your theatre is not advantageous to keeping people further away from the projection beam.

[Tom Bert]

There was an InfoT sent out by Barco as well on this topic in December 2020. The new rules are enforced (since 20/12/2020) in the EEA (European Economic Area); for now you are only advised to follow them in the US. The new element is that the regulations around safety distances that have been in place since 2015, now retro-actively apply to all (Risk Group 3) projectors, so also lamp projectors brought to market in 2009-2012. Safety distances for lamp projectors were already applicable since 2015 for new projectors, but coincidentally non of the major cinema brands brought a new lamp projector to market after 2015

[Frank Cox]

If I understand this correctly, then, one way to make up the needed distance for the safety area would be to move the projector further back in the projection room. If you needed another two feet, for example, then you could either barricade things so people have to stay two feet further back or you could move the projector back two feet in the projection room and (I guess) make a larger port for the light to go through into the auditorium.

I've never heard anything about this before, at all. Maybe it doesn't even apply in Canada and if it does (or will), maybeI already meet the requirements anyway. I frankly have no idea if I do or I don't. It's never come up. I can see where some of these guys with projectors hanging from the ceiling might not be able to meet the specs without some significant modification to their auditoriums.

[Carsten Kurz]

From Barco's InfoT1488:

• This is valid retroactively - also for the ones developed/certified before 2015, as long as they are still being sold.

So, if someone owns a projector that was brought into market before 2015, but is no longer sold, one is safe?

It also says:

Scope:
All new installations, including displacing projectors or second hand projectors. It is advised though not obliged to also revisit existing installations with lamp projectors with eye on optical safety distances.

[Harold Hallikainen]

We had to test for this on IR panels. It's especially critical there since the eye's pupil does not contract in the presence of IR as it does with visible light, and the person does not turn away from the "bright light" as they do with xenon and visible laser. This all makes sense to me, as we do not want to blind people. Ideally the standards are based on actual data of injury.

Harold

[Carsten Kurz]

Were there actual regulations demanding this? This would also be the same for IR-Transmitters for 3D systems then (e.g. XPanD, Volfoni).