Means of egress lighting controls

[Grouch1980]

Hi all,
This is from the 2014 NYC Building Code (which is the current building code for NYC):

"1006.2.1 Sensors and controls. Automatic, occupant sensor or photosensor lighting controls shall be permitted within means of egress, provided that the illumination level is not reduced to a level below the minimum requirements of Section 1006.2, and the switch controllers are equipped for fail-safe operation ensuring that if the sensor or control fails, the lighting levels will beat the levels required by Section 1006.2."

Here is the lighting levels required by 1006.2:
1006.2 Illumination level. The means of egress illumination level shall not be less than 1 foot-candle (11 lux) at the walking surface.

My question is:
Can i still have a light switch, in addition to the ceiling occupancy sensor, on the wall that shuts the lights COMPLETELY off? or does that violate 1006.2.1?

 

[Grouch1980]

FYI, this is during normal operation of the building, i.e. we're NOT in a power loss situation where backed up by generator or inverter, or any lighting circuits were switched to EM via a UL924 relay. This section that I posted is during normal operation.

 

[Fred B]

Hi all,
This is from the 2014 NYC Building Code (which is the current building code for NYC):

"1006.2.1 Sensors and controls. Automatic, occupant sensor or photosensor lighting controls shall be permitted within means of egress, provided that the illumination level is not reduced to a level below the minimum requirements of Section 1006.2, and the switch controllers are equipped for fail-safe operation ensuring that if the sensor or control fails, the lighting levels will beat the levels required by Section 1006.2."

Here is the lighting levels required by 1006.2:
1006.2 Illumination level. The means of egress illumination level shall not be less than 1 foot-candle (11 lux) at the walking surface.

My question is:
Can i still have a light switch, in addition to the ceiling occupancy sensor, on the wall that shuts the lights COMPLETELY off? or does that violate 1006.2.1?

The occupancy sensor or any other switching means can only shut down lighting to the point of the minimum lighting level. So from what is stated and installation I've done if the space is required to meet 1006.2 level then any switch that terminates or dims lighting to a point less than minimum candle power would be a violation. There are lights that build in a minimum backup lighting via battery backup, or in this requirement it is split power source, one from switched source and another direct wired, thus staying on at reduced lumen, the direct wire one is usually includes the battery backup, and both on the same circuit.

 

[Grouch1980]

Thanks. What type of battery back-up is this? It sounds like it is remote from the light fixture. and how long should it last?

 

[Fred B]

Thanks. What type of battery back-up is this? It sounds like it is remote from the light fixture. and how long should it last?

They have troughers with the emergency balast built in, or can buy a replacement balast that has the battery backup built in. These are set to run on backup for the usual minimum time of 90 minutes.

 

[Grouch1980]

They have troughers with the emergency balast built in, or can buy a replacement balast that has the battery backup built in. These are set to run on backup for the usual minimum time of 90 minutes.

What if no one is the corridor / means of egress for more than 90 minutes though? The battery will die, and the lights turn completely off... now we're in violation of that section no?

 

[GoldDigger]

What if no one is the corridor / means of egress for more than 90 minutes though? The battery will die, and the lights turn completely off... now we're in violation of that section no?

The lights will only operate on battery if the normal power fails, not if they are switched off,
To accomplish this each battery location needs to be fed by both continuous power and switched power.
In some cases the lights may need to turn on in case of fire alarm or other emergency even when normal power is not interupted. These are NOT intended to allow indefinite continued occupancy of the building after power is lost.

 

[Grouch1980]

These are NOT intended to allow indefinite continued occupancy of the building after power is lost.

Just to clarify, the operation I described is while normal power is available. It's not during a power outage.

So in order to achieve that minimum illumination level in the corridors / path of egress while normal power is available, let's say we have 20 light fixtures in the corridor / path of egress controlled by 2 occ sensors and one wall light switch, and either the switch is turned off or the occ sensor senses no one... each and every light fixture needs needs an integral battery to maintain that minimum illumination?

 

[Grouch1980]

The occupancy sensor or any other switching means can only shut down lighting to the point of the minimum lighting level.

Reading the section again, it sounds like it only applies to occ sensors. 1006.2.1, from my original post, only says 'automatic, occupant sensor or photosensor lighting controls'. it seems like you can still kill the power completely with light switches. I don't know.

 

[Fred B]

Just to clarify, the operation I described is while normal power is available. It's not during a power outage.

So in order to achieve that minimum illumination level in the corridors / path of egress while normal power is available, let's say we have 20 light fixtures in the corridor / path of egress controlled by 2 occ sensors and one wall light switch, and either the switch is turned off or the occ sensor senses no one... each and every light fixture needs needs an integral battery to maintain that minimum illumination?

No, battery only if used as emergency lighting. There are a variety of ways to accomplish this as an energy efficiency method. It seems that is what you are trying to accomplish. Code requires lighting to never fall below the 1 candle.
1. half the fixture operate from the switch and other half of each fixture live, or you can have how ever many fixtures that are needed to maintain the minimum illumination without switching and the remainder on a switching device.
2. If you have an occ sensor that only dims and not total power off it is permissible to use that as long as maximum dimming does not result in a lighting level below the minimum rate listed.
So for your example of 20 lights. If you can maintain minimum area light coverage from 10 lights at half power, those can be set up from a dimming occ., and the other 10 can be on an occ switch and turned off when not occupied. Or you can have all the lights dimming via a dimming occ sensor only down to the minimum allowable level. Another way is to use a split fixture that uses 2 ballast having each section controlled as above 1 ballast dimming and the other switched.
One company mfg such devices is Aquity Controls.

 

[Grouch1980]

ohhhhh.... battery only used during emergency only. that makes sense. ok, let me reread everything and see if I can follow.

 

[Grouch1980]

Or you can have all the lights dimming via a dimming occ sensor only down to the minimum allowable level.

This is the easiest way I find. But wiring it this way, with all lights being dimmable, how do you prevent the light switch on the wall from killing power completely?

Is it from what Golddigger said?: "To accomplish this each battery location needs to be fed by both continuous power and switched power." What if my lights are connected to a central emergency inverter instead?

 

[Grouch1980]

The way i'm reading 1006.2.1, from my original post, is that the dimming down to the minimum lighting levels allowed, doesn't include the light switches. 1006.2.1 only refers to automatic sensors, whether occupancy or daylighting sensors. It sounds like you can kill the power completely with the light switches. Is this right or wrong? or both!