Darkness in a venue (church, theatre)

Derek220

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Dec 17, 2019
Location
Omaha, NE
What are the considerations (specifically life safety codes) regarding the light level in the house during a theatrical performance? (under normal power circumstances. Not when power fails and emergency batteries or generators kick in)

Why I'm asking:
I've been operating lights for a church and during an event, I was asked to turn off most of the lights. This left the house in a rather hard to navigate darkness (the stage was lit).
 

tdrga

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Feb 13, 2011
Location
Central TX
What are the considerations (specifically life safety codes) regarding the light level in the house during a theatrical performance? (under normal power circumstances. Not when power fails and emergency batteries or generators kick in)

Why I'm asking:
I've been operating lights for a church and during an event, I was asked to turn off most of the lights. This left the house in a rather hard to navigate darkness (the stage was lit).
The International Building Code has light level requirements in Section 1006 "Means of Egress Illumination." In general, it is not less than 1 footcandle (at the walking surface) which can be reduced to 0.2 footcandles during performances as long as the fire alarm system will increase the light level automatically when activated.
Of course, your AHJ may have different requirements or enforce different codes with higher levels.
You should be able to review a current copy of the Code at a local library or you can find older versions online.
Your organization is always able to establish a policy for higher light levels if warranted - if your primary audience is elderly, I would go brighter.
-Todd
 

Derek220

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Dec 17, 2019
Location
Omaha, NE
Thank you so much for the code references. Perhaps each year of the IBC has similar requirements for illumination of means of egress, but out of curiosity which year were you looking at?

A quick glance at NFPA 101 shows similar requirements to IBC in section 7.8 (In assembly occupancies 0.2fc is allowed during a performance.)
 

tdrga

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Feb 13, 2011
Location
Central TX
Thank you so much for the code references. Perhaps each year of the IBC has similar requirements for illumination of means of egress, but out of curiosity which year were you looking at?

A quick glance at NFPA 101 shows similar requirements to IBC in section 7.8 (In assembly occupancies 0.2fc is allowed during a performance.)
I referenced the 2012 version of the IBC. That was the code version I had regarding illumination measurements relating to a lawsuit from an audience member's trip and fall during a performance. And that's all I can say about that...
-Todd
 

BillConnerFASTC

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Location
Clayton NY 13624
Generally, when occupied, aisles, cross aisles, and all walking areas other than aisle accessways (code for that space between rows of seats) at 0.2 fc. That is minimum over entire width of aisles - not average.

Interestingly, the LSC is much more particular about the emergency lighting - averages, minimums, and contracts ratios.

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Few seat end aisle lights do the job, the Irwin "concealed" aisle light being one that generally does. Some years ago a lighting designer proposed changing form 0.2 to 0.1, his substantiation being that almost no facilities he measured met the 0.2 requirement, and IIRC around half would meet the 0.1.

This is illumination - light directed on the floor. There is no provision for illuminance meeting this code requirement, such as the Tivoli style in transitions at the edge of the aisles.

Ramped and level aisles without obstructions and other hazards are not too much of a problem. Aisle stairs, especially if the treads are not uniform and/or risers exceed 7", seem to be a greater hazard.
 

tdrga

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Feb 13, 2011
Location
Central TX
Generally, when occupied, aisles, cross aisles, and all walking areas other than aisle accessways (code for that space between rows of seats) at 0.2 fc. That is minimum over entire width of aisles - not average.

Interestingly, the LSC is much more particular about the emergency lighting - averages, minimums, and contracts ratios.

View attachment 19343

Few seat end aisle lights do the job, the Irwin "concealed" aisle light being one that generally does. Some years ago a lighting designer proposed changing form 0.2 to 0.1, his substantiation being that almost no facilities he measured met the 0.2 requirement, and IIRC around half would meet the 0.1.

This is illumination - light directed on the floor. There is no provision for illuminance meeting this code requirement, such as the Tivoli style in transitions at the edge of the aisles.

Ramped and level aisles without obstructions and other hazards are not too much of a problem. Aisle stairs, especially if the treads are not uniform and/or risers exceed 7", seem to be a greater hazard.
The IBC does have similar or the same language as the LSC you quoted above for emergency lighting (as opposed to normal power "House Out" levels). It seems that the codes are pretty much in agreement on this particular issue (which is good!).
-Todd
 

BillConnerFASTC

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Jan 30, 2010
Location
Clayton NY 13624
Yes they do pretty much agree. I was looking at 2018 of both. Harmonizing the codes is one of those things I've worked on since I got involved in code development in 1987. To few of these buildings built to have different requirements each time.
 
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ACTSTech

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Nov 13, 2019
Location
USA
We're fighting this in our renovation. The fire codes at the local level conflict with state codes and without permanent seating, we're not sure who to follow. The local fire codes are a mishmash of new regulations written as a result of devastating fires as well as ancient tomes from when a lot of places had candle-lit fixtures (mostly left in place for churches who still use candles for parts of services). On top of that, the regulations also are dependent on how the building is zoned... The latest proposal, because the seating could theoretically change due to the performance, is to leave the house lights on at 10% at all times. This seems to be arbitrary, because they've never measured any illumination, so theoretically I could put in one 100-watt incandescent bulb and they would be okay with it.

Does anyone know whether the amount of light coming from the stage into the house is ever taken into account? That's a random question, I know, I'm just curious. I've been in houses with white walls which are lit up brighter than their walkway lights due to bounce.
 

Malabaristo

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Location
Wisconsin
Does anyone know whether the amount of light coming from the stage into the house is ever taken into account? That's a random question, I know, I'm just curious. I've been in houses with white walls which are lit up brighter than their walkway lights due to bounce.
I'm sure people have made that argument before, but it doesn't really apply to code-mandated minimum illumination. Stage lighting changes depending on the show and the specific moment, so you can't count on it to be there all the time. The closest thing I've seen in more acceptable use was a set of theatrical fixtures dedicated as aisle lights with either shutter cuts or custom gobos (think Tetris shapes) to avoid spill on the audience. That does let you turn the houselights off during the show, but those fixtures would not count as emergency lighting. You would still need some other system to provide the minimum illumination if there's a power failure or other emergency.
 

macsound

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Jun 15, 2018
Location
San Francisco, CA
I'm wondering how the code differs for permanent vs temporary seating. I know linking the chairs, therefore creating predictable aisles and preventing the pileup of chairs is required, but since the room is classified as general use, there's no predefined aisles to light with aisle lights.

When I've worked at venues that had inadequate ambient lighting that would sometimes leave the houselights at 10% during tech week so people could see when walking around. I'd intentionally take them to 0% to prove if you can't see to get backstage, the 80-year-old isn't going to be able to see to take a mid act 1 pee.

One theatre I loved made the genius move to have dimmer and dimmer bulbs in the vestibule from the lobby to the theatre so the one closest to the door into the theatre was only a 25w blue bulb. Obviously, it also made it better for light leak, but the 60w in the outer doorway to 40w halfway down to 25w allowed even the slightest ability for your eyes to adjust before being plunged into darkness.
 

ACTSTech

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USA
Oh, I'm not suggesting that the bounce and spill from the stage be counted as fire safety illumination at all. I just find some of the archaic and random numbers that seem to be tossed out there to be, well, random. Is someone walking through with a light meter measuring 1 foot candle and saying this is enough? Like one person on here told me when I was asking about stage illumination, there's a difference in everything that can't be compared. LED is different from incandescent, and color temperatures change things too. It's somewhat subjective.

Like I posted, the fire inspector said he'd consider 10% good enough. I didn't respond, but 10% of what? If I have a 100 watt bulb in a floor lamp, and a 1000 watt PAR 64, and a 25 watt reading light, 10% is totally different, but still 10%. I've had arguments with people over lighting backstage, some want blue, some want red, some want it high, some on the floor, again, it's subjective. I usually err on the side of caution, but I enjoy seeing what others think and have experienced.
 

RickR

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Sep 18, 2009
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Spokane, WA the great "Inland Northwest"
Getting an agreement with your inspector is the ultimate goal. Codes and standards are key, but not the last word.

Last I looked, IES recommendations for aisles was 10-15 foot candles. 10% of that is well above most codes but not ridiculous. Keep in mind that ALL light sources fade with age. Suggesting a target illumination might remove some of the vagueness you have.

With a changeable seating layout, you might consider a grid of narrow beam house lights that can be controlled independently. That or moving fixtures around, show by show.
 

Malabaristo

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Jul 11, 2008
Location
Wisconsin
I'm wondering how the code differs for permanent vs temporary seating. I know linking the chairs, therefore creating predictable aisles and preventing the pileup of chairs is required, but since the room is classified as general use, there's no predefined aisles to light with aisle lights.
The code doesn't care, because it doesn't say you have to light just the aisles. With fixed seating you can pretty easily be more specific about only lighting the required areas, so that's the default. With moveable seating, you either need moveable lights or general illumination to hit the same targets anywhere an aisle might end up on a given show.
 

ACTSTech

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Location
USA
The code doesn't care, because it doesn't say you have to light just the aisles. With fixed seating you can pretty easily be more specific about only lighting the required areas, so that's the default. With moveable seating, you either need moveable lights or general illumination to hit the same targets anywhere an aisle might end up on a given show.
That's what our fire inspector said, that because there's no "goal" area for people to hit, like and aisle that's always there, you have to provide illumination over a general area. It's the details that get blurry after that which are causing the headaches.
 

jtweigandt

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Aug 2, 2013
Location
Moline Il
I went to a performance of the "Cinderella" National Tour at the University of Illinois (Fairy Godmother was a schoolmate of our daughters)
For the upper deck in the arena reconfigured as Theater space, they used long throw Elipsoidals to hit the aisles/stairs in the upper decks. (could have been better aimed though)

I wonder about a fleet of cheap chinese movers.. you can re config for where ever the aisles occur? aim at the aisle, dim down to taste.. They threw these from the front.. so the "fan"
would be able to align with the "fan" or aisles. But I think you could have an array high and toward the back that might do.
 

tjrobb

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May 14, 2009
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Cedar Rapids, Iowa
Or you could do like our 9000 seat arena plus convention center, fake the emergency lighting system. They used latching relays and tested the system by popping the main; of course it worked... there's just nothing sensing a power cut if they're not already On. Just a few empty conduits and unconnected sensors.
 

ACTSTech

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Nov 13, 2019
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USA
Just had a meeting with the architect and electrician and they suggested that we recess rope light in the floor like you see in movie theaters. If you calculate the output by linear foot, it would be about 80 lumens, so 7 or 8 fc, which is well above the limit. Anyone have thoughts about this?
 

jtweigandt

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Location
Moline Il
We have some rope light embedded in the floor in a few spots. Had to recently replace the old incandescent. All the new stuff was LED and WAY TOO BRIGHT.. Fortunately whatever transformer they were using to drive them was happy when placed on an old analog style household twist dimmer switch. So I would say.. yea, but with the provision of dimming. Then if they are really picky put a light meter on it and mark the switch position, or put another switch in series and the dimmer in a clear thermostat vented lock box if they demand you be able to leave at a setting.
 

microstar

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Jan 19, 2014
Location
Lawton, OK
I have always found "aisle lighting" like this distracting when sitting in aisle seats, but just my 2 cents.
If you do this, I would seek out very high quality LED strips made for this purpose and not have them on all the time. But if on a switch, of course someone has to remember to turn them on and off.
Maybe a relay that turns on when it senses DMX from the console?
 

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