New installation - sound and lighting cutout?

[Stutwo]

We're currently going through the process of ironing out details for an infrastructure refit at our college venue. One of the contractors involved is adamant that as part of the install there must be a system that, in the event of a fire alarm, cuts the sound AND the stage lighting feeds by gently ramping both down to zero (which I'm pretty sure is a "feature" of the system he really wants to sell). Now, it's a fair while since I was involved in the regs of an installation to this extent and I would like to be able to tell him we don't need such a thing. Sound, I can understand (but is it a requirement?), but lighting?

 

I'd be hugely grateful if anyone can enlighten me on this one.

[Ynot]

Personally I'd be going the other way and insisting that this contractor backs up his claims with specific references to the legislation he's supposedly citing.

 

I would also be VERY cautious about having a cutout on either LX or sound - sound is a big NO for me because unless you have an additional system, redundant except in the case of a fire alarm, you may well need to retain the PA (both to auditorium and backstage areas) for announcements, emergency or otherise.

 

LX cutting out is maybe not so much of an issue, but again assumes that this would necessitate the bring up of working lighting and such like - but I'd still be wary.

 

However, from a purely practical point of view, how would the system deal with false alarms? Either accidental or malicious...

Whilst in normal workplace situations the creed is that any alarm is valid until proven false, therefore everyone out until proven, the trend for performance venues can be slightly different due to the nature of the beast and the number of people in a single place (ie the audience). So in many cases (including our venue) the drill is that should an alarm be sounded, there is only a visible indication in the auditorium (strobe above stage). This allows for the performance to be paused and house lights brought up, with a 'standby' announcement being made over PA. The nominated fire marshalls will quickly investigate the supposed source of the alarm and determine whether it's valid, and more importantly the location thereof, and then the dept heads can then advise cast, crew and punters that either it IS a false, or if valid, they direct the people to the right exits.

 

The LAST thing you need is for a building full of bodies all potentially heading towards the fire...

 

My opinion?

He's trying to pull a fast one to get you to have some rather UN necessary kit.

[jonhole]

Our Chilli dimmers actually do the opposite - you can connect your fire system into them so when the alarm sounds the dimmers fade UP all the channels to ensure there is plenty of light available throughout the space.

[paulears]

If the fire system provides voice alarm, as our one does, then I can see the point in cutting sound power - In our venue it cuts the entire facilities panel stage right so that's usually sound - but sometimes LX 'borrow' from this panel, so we lose power to the movers on the truss and some on stage.

 

I see no sense in the lighting going out whatsoever. In fact, if I did a risk assessment, cutting lighting power could make exit less easy, not more - so unless the company could provide me with evidence of a safety improvement, I would reject it on safety grounds - and few companies would persist in writing in recommending a more, not less dangerous system.

[Junior8]

Simple. Ynot is right - in these cases always ask for the legislation/reg involved.

[Brian]

... insisting that this contractor backs up his claims with specific references to the legislation he's supposedly citing.

+1

[Stutwo]

Thanks all for the info and advice, I will press for the legislation supposedly involved. I don't believe the Fire alarm is a voice announcement system, but will check.

[Andrew C]

I'm sure the advice above is correct, but I'd like to pick up on a point. If all of our dimmers got faded up on alarm, there would be a very big bang as the main fuses departed this mortal coil. A blunt instrument, methinks. I'd want to be able to specify which dimmers faded up.

[WiLL]

In general be VERY wary when preparing for installs of what a contractor tells you you NEED. Especially contractors who may not be theatre specific i.e. electricians installing the 3-phase supply etc. Go over everything with a fine tooth comb and be very specific about how you know it all has to work.

[andy_s]

I too don't believe that such explicit legislation exists, certainly it never came up in the building project I was involved in a few years ago, which had a large and quite complicated fire alarm system, so you must insist on chapter and verse. However, if the contractor is worth his salt, I'd expect him to be able to provide an interpretation of legislation or CoPs that suggests he is correct, (otherwise known as "sales pitch") so you would be advised to have a viable alternative ready to counter his "proof".

 

personally, I'd argue that this level of automation might be appropriate in a shopping mall, but not in a theatre in "performance mode". I'd suggest that the lighting and sound equipment is always attended by trained and responsible operators who are able to render the equipment in the appropriate state (lights up or down, sound on or off as defined by the venue Fire Risk Assessment) in the event of a fire alarm. Far more important in my view than an automated system intervening in these circumstances is the setting up of a foolproof system of communications to ensure all staff are fully aware of what is happening and what steps need to be taken when the alarm goes off.

 

I can perhaps see the value of something that turns the sound system on in certain circumstances, eg an event where there would otherwise be no need for the PA, but a seperate voice announcement system* attached to the alarm panel would be a better approach in my view.

 

* or a confident duty manager with a loud voice!

[sleah]

Definately a contractor with little or no knowledge and trying to sell something.

An occupied building such as a theatre doesn't need to have automated triggering for a fire alarm (in the occupied area), so long as there are one or more humans who can respond and trigger the alarm and instigate evacuation following a pre-determined policy. This will almost certainly be a license condition.

 

If all people in the venue will just run round like headless chickens then I can see justification for such a system, but then they would probably in serious breach of their license (as above). A (suitably briefed in procedure) sound op is by far the best person to deal with sound, the same with lighting.

 

The lights offer no additional danger or hazard whatsoever to a building fire when you think about it. As the auditorium or pack room burn, it will simply cause upstream breakers to pop. A light burning by an external source is no more likely to 'explode' than one with a fault. Indeed even if a fixture or dimmer DID explode when burning, any human occupants would be toast by then anyway.

And why would lighting left on in an unaffected area suddenly pose a problem?

In fact, in the event of a gas leak, any alteration to the lighting could easily CAUSE an explosion!

Once the fire brigade are on scene THEY will look to killing any electrical supplies at source anyway.....

[Robin Pratt]

I too am fairly confident that there is no legal requirement for this. There may be a case for implementing some of these functions, subject to our old friend the risk assesment.

 

For instance, if you expect performance sound levels to be high enough to render a standard fire alarm useless, then there could be a case for installing something like the Green Halse Electronics mute 16, which sits between your sound desk and you amp racks, and in the event of the fire alarm being triggered will mute the feed from the desk and insted allow a recorded emergency message to be played through the PA. I think, however, that this approach is more suited to night clubs etc. than theatres.

 

As regards the lighting, there might be a case for cutting the power to the grid, but only if the same sytem also switches on the house lights/working lights/escape route lights etc. Again, perhaps more suited to the club/disco scene...

 

None of this, in my view, is a true substitute for having the system attended at all times by suitably competant people but such measures may be appropriate as a backup if the staffing levels cannot be guaranteed

[Junior8]

I have just dug out the Guide to Fire Precautions which I assume is still current and there is no mention of this. I have though googled and found one local authority in NI which specifies that in the case of an entertainment where the sound levels render an audible alarm ineffective that the alarm should override the PA system.

 

In theatre situations the alarm should never be an automated voice announcement - at least in my view. I was always taught that in theatre the alarm must be readily seen by the performers/staff but not initially by the audience. (Are code words still used?) The aim is for an orderly evacuation supervised by the appropriate attendants not a mass Exodus triggered by everything going dark and sirens belting away!

[Robin Pratt]

(Are code words still used?)

 

 

I think "Mr Sandy" does still make the odd appearance....

[Yorkie]

What you would want is power being cut to is any smoke effect or similar.