lxkev Posted February 27, 2008 Share Posted February 27, 2008 Well I've been pulling my hair out this week as new fire alarm system has started to be installed. For some reason it was necessary to discuss it with the people who use the building graahaaa Apart from having heat and smoke sensors installed in stupid places, and not being able to disarm them.. I’ve now been told the alarm system is going to cut all power to lx and sound.....Thus leaving 350 people sitting in the dark with a very loud siren going on off... Does anyone else out there have to put up with this? Is there any information out there about fire alarm system installed in theatre , in special regards to the cut all power situation? And during a performance do we have to have the heat sensors still on which are located about 20cm above 10 parcans..... If anyone has any do and don’ts it would be much appreciated. Link to comment Share on other sites More sharing options...
grizzly Posted February 27, 2008 Share Posted February 27, 2008 I’ve now been told the alarm system is going to cut all power to lx and sound.....Thus leaving 350 people sitting in the dark with a very loud siren going on off... Surely any fire alarm system that causes LX and PA power to disconnect on activation should also cause some sort of emergency lighting to come on, so the audience doesn't have to evacuate in the dark. Link to comment Share on other sites More sharing options...
J Pearce Posted February 27, 2008 Share Posted February 27, 2008 I can understand the need for an alarm to cut PA, having been in a situation where an alarm was set off and could not be heard FOH over the level of the PA. I'm not sure why the alarm would need to cut lighting too, unless there was significant likelihood of the lighting supply being used for sound?With lighting often being such a large current consumer it seems a lot of money to spend out on relay switch boxes for no reason. Link to comment Share on other sites More sharing options...
kerry davies Posted February 27, 2008 Share Posted February 27, 2008 I presume that this link: http://www.communities.gov.uk/documents/fire/pdf/144845 has been given to the installers? Somewhere in there it says that smoke detectors (at least) may be disconnected whilst using smoke in a theatre. I'm not specifically "theatrical" but you should also have a copy of the Technical Standards for Places of Entertainment, if not you can order one from here: http://www.abtt.co.uk/PDFs/ABTT%20Publicat...m%20Current.pdf which also should help, though I'm not absolutely sure.If your theatre is part of an educational establishment then there may well be other parameters that come into play. Good Luck! Link to comment Share on other sites More sharing options...
Light Console Posted February 27, 2008 Share Posted February 27, 2008 Well...if our fire alarm goes off, you don't hear it for one thing. As it is a concert hall, we have lots of red strobes in obvious places. The house lighting system is linked to the alarm, and will turn all house lights to full. And no matter what you do with the controls, they will not turn off until the alarm has been reset. The air handling (which moves 5 cubic meters of air a second) shuts down instantly.The downside is that we can isolate the detectors in the roof of the hall, but in the undercroft (which has a grille between the rows of seats for air) and inside the air handling ducting we cannot.This means that we are limited to the amount of smoke we can use, and with such a large amount of air moving, it doesn't hang about for long.I don't think that any system could leave people in the dark these days if set correctly. Our dimmers are set to hold previous state if DMX is lost. Link to comment Share on other sites More sharing options...
danburns Posted February 27, 2008 Share Posted February 27, 2008 I don't think that any system could leave people in the dark these days if set correctly. Our dimmers are set to hold previous state if DMX is lost. But if the OPs dimmers are wired into the contactors...then it won't matter whether they are set to hold DMX or not - they'll go off. Several venues I've been to will have a pre-alarm which activates strobes and gives you a grace period to acknowledge that the alarm has been activated. Which in my limited experience is surely a good thing - you don't have an audience full wondering where to go when the alarm goes off. Link to comment Share on other sites More sharing options...
Bryson Posted February 27, 2008 Share Posted February 27, 2008 I managed to persuade the fire alarm contractors that they really didn't need to cut the power to the amps when the alarm went off - installing a box that disconnects the signal (ie: 6 very small relays) was considerably cheaper, easier, and more forgiving on the amplifiers! Doesn't help if you use a system other than the installed house system, mind. Link to comment Share on other sites More sharing options...
Wuddy Posted February 27, 2008 Share Posted February 27, 2008 I suggest that you take a look at this document, Fire Safety Risk Assessment, theatres, cinemas and similar premises 8 This is HM Govs. most upto date guidance and is available to download free from HERE, when you view it I think page 59 is the section on fire alarms Link to comment Share on other sites More sharing options...
paulears Posted February 27, 2008 Share Posted February 27, 2008 Well, if the detectors can't be switched off, they'll soon be changed after you have evacuated a few times, the punters complain, and the productions refuse to return. The use of smoke and haze is implicit in many riders, so if you cannot permit these kind of shows, they won't perform - so it will have a real impact on income. We have no detectors whatsoever in the auditorium or stage area, only in dressing rooms and off-stage areas isolated with fire doors. Our PA power power panel runs through a fire alarm controlled contactor, but lighting doesn't. Link to comment Share on other sites More sharing options...
Nick S Posted February 27, 2008 Share Posted February 27, 2008 Apart from having heat and smoke sensors installed in stupid places, and not being able to disarm them.. ards to the cut all power situation? [...]And during a performance do we have to have the heat sensors still on which are located about 20cm above 10 parcans..... I've never heard of false alarms caused by heat sensors like that. Maybe it does happen, but I've just never seen or heard of it. An ideal scenario consists of being able to isolate (which is somewhat different to 'turn off'...) smoke sensors, whilst keeping heat sensors on. Isolation can also involve a dead man's switch system, whereby smoke and heat detectors are kept on, but won't trigger the alarms until after a set number of seconds. Cutting power to LX is sensible if you have an appropriate emergency lighting / working light that's set to turn on. Otherwise, it's up for debate. It would depend on what you have in your venue. Link to comment Share on other sites More sharing options...
Dmills Posted February 27, 2008 Share Posted February 27, 2008 I have just been doing the new fire alarm thing... What we have is a all automatic detection in the auditorium and stage areas being able to be isolated by a key switch in the stage door office. In addition for performances the automatic detection can be set to run a two stage alarm with a short delay to give time to investigate and cancel the alarm if appropriate. Setting a zone to isolated disables setting the security system, so it is not forgotten when locking up. Manual call points (or activation of a second automatic sensor) always go to full alarm instantly. Full alarm is tied to the auditorium working lights and will automatically power them up upon alarm (Very obvious). We have interfaces available to PA, but I have that hooked to a strobe by the desk on the grounds that the PA may be useful for evacuation (it is not required for our evacuation plan, but having it does not hurt). Commissioning these things is a soul destroying activity, almost as bad as doing the new heating system (nightmare). Regards. Dan. Link to comment Share on other sites More sharing options...
kerry davies Posted February 27, 2008 Share Posted February 27, 2008 Hi Wuddy, yes that's the badger in my first link. Just FYI the detector stuff is on Pp21/22 and "further guidance" is on Page 59. I think 21 is where it states that detectors can be isolated in theatres. Link to comment Share on other sites More sharing options...
Light Console Posted February 27, 2008 Share Posted February 27, 2008 ...But if the OPs dimmers are wired into the contactors...then it won't matter whether they are set to hold DMX or not - they'll go off... Sorry missed that bit, I sit corrected. Link to comment Share on other sites More sharing options...
Steve Cavill Posted February 27, 2008 Share Posted February 27, 2008 Not sure if this has already been covered, however, surely, its exactly the same as wiring a club up. The sources are to be disconnected, but the mixer is to stay on, so that announcements can be made over the PA system. Lighting shouldnt be disconnected in any way shape or form, as this would plunge the venue into darkness, creating an even greater hazard of "x" amount of people in a dark burning building. The system should also be isolatable surely... Link to comment Share on other sites More sharing options...
Tomo Posted February 28, 2008 Share Posted February 28, 2008 Many dimming systems have a "Panic" or "Fire Alarm" contact closure* input that automatically forces the dimmers into a known state - ignoring the DMX input. So you can easily interface with a fire alarm system to force the houselights on if it's triggered.That's my favourite system for a fire alarm/lighting interface, as it's very cheap and very effective. The options you get depend on the dimming system chosen of course! (*Normally Open, Normally Closed or whatever) Link to comment Share on other sites More sharing options...
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