safety curtain

[mikienorth]

Hi I have worked on Irons for a number of years this includes installing new ones and servicing existing ones I have never heard of a safety curtain linked to a fire alarm system as it has to be completley mechanical and not be affected by anything electrical to drop in.As you know there is a release on the stage and you should have a cable operated release by the stage door or other exit so that it can be deployed remotely I hope this helps

 

I dispute this, Irons of a more recent creation are electronically controlled, with a battery backup system allowing them to be dropped in the event of a power failure. Older irons, are, I am well aware, controlled entirley mechanically with an electric motor to lift them. Newer irons are still gravity controlled, but are held up by an electronic brake.

Only speaking from the irons in venues I have worked in...

And I have read specs calling for a fusible link to be installed causing the iron to fall automatically, so why not a fire alarm? I agree that such a large piece of equipment that has quite a dangerous style of guillotine operation should not operate automatically, it should be called in, or operated by the last person to leave...

 

Anyway I've drifted OT, sorry guys.

 

If work needs doing on stage, or in the stage area, or in the region of the arch, then a member of crew should be in to look after the area, in case of damage - see Paulears' comments about the cutting of a cable over the winter for a good reason why contractors need watching.....

[gareth]

I can second what Mikie says re. not having to be mechanical - I worked in a venue (built in 1994, so not exactly very recent) the safety curtain in which was controlled electrically rather than via a solely mechanical release.

 

To comment on Mikie's other point re. fusible links - generally, I'd like to think that by the time a fire became hot enough to melt a fusible link and drop the iron anyone in the building would be long gone! On the other hand, an interface to a fire alarm system would surely result in the iron being 'told' to drop every time the alarms triggered, even if it was a false alarm - not great, I'd have thought!

[Rowan]

Gareth

 

I suppose this depends on the type of alarm that the building has. If it is the two stage alarm then I guess it would not be as much of a problem.

 

In the venue you worked at, did the iron require power to drop? I would have thought that a system like this would be designed to drop in if it lost power.

 

It is my understanding that these days it is not as much of a requirement to have an Iron. I know of a couple of number one touring venues who although they have an Iron are not required to!!

[mikienorth]

But with fusible links designed to fail at a range of temperatures, and spot boxes reaching temperatures of 50 degrees in summer sometimes, and fusible links operating at 70, what is the temperature in the grid during some events? Uncomfortably warm? Bit hotter and the iron drops?

Ooooer.

 

I believe that should the fire brigade/first man into the building want to drop the iron, if not already done during the evacuation, by the Duty Technician/last man out, then they should decide when it falls, not a peice of what is, effectivley, solder.

A stage under a fire is dangerous enough without a 5-6ton sheet of metal falling in unnanounced, don't you think?

 

A two stage alarm goes into evacuate mode (second stage) after a period of time given to investigate a fire. During this stage 1 time, people can still be performing, and nothing happens to stop a show until the decision is taken either by theatre staff, or the time delay or second kknock on the fire alarm (more than one detection of fire = spread = get out)

Were the iron to drop on the second stage is it not plausible that the theatre manager might be on the stage making an announcement about getting out? Splat?

 

I have made fire alarms do many things, open doors, close doors, turn things on, turn things off, start extracts, shut ducts down, turn off gas, call people (not normally the fire brigade, the call centre actually does that bit for you), evacuate in stages. The capability of Normally open and normally closed contacts is amazing when you get them going properly. Making things fail 'safe' as well is fascinating sometimes, but the automatic operation of an iron isn't something I would like to see. In some ways it may preserve life, in others it may endanger it...

[Ken Lovelace]

Interesting commits on the operation of a fire curtain. In our theatre the fire curtain is manually operated, with a cut line stage left and a pull handle stage right. Every twenty feet on the steel cable between the pull handle and the cut line there is a fuse link. Sitting in our booth yesterday, installing new equipment I hear a large racket from the stage. My first thought was that I had a batten coming in on it's own and sounded like it was moving pretty fast. When I looked to the stage I see the fire curtain half way down and moving to the stage floor. After the fire curtain is all the way in I go to investigate. I take a trip to the grid to see what might have happened and find a fuse link has come apart, which caused the fire curtain to come in. I am a bit perplexed that this happened, but am thankful the building was empty except for me and that I was not near the stage when this happened. If this had happened during a load in or during a show, I would feel sure that either equipment or worse, people could have been injured. I think some sort of change needs to be made to make this SAFTY DEVICE safer. Any suggestions?

[wako_jacko]

my only experience of something being 'trapped' under a fire curtain is the l'head theatre a few years ago - it came to rest on a 13 amp power cable extension lead spindle (can't remember what it's called) thing. and did not damage it at all - wouldn't wan't to be trapped under it - but if a small metal handle is not even bent out of shape by it - I don't think that anyone would be badly hurt by it.

[Ellis]

The safety curtain is for the safety of the audience and is only required as part of the theatre licence. Outside performance times, it is up to the theatre management to determine policy.

 

A local theatre has recently had its safety curtain reinstated to protect the heritage (and funded for that purpose). That dictates that it be in when the technical staff are not around.

 

The curtain is counterweighted and can (just) be held out by a technician holding the bottom. It is operated by a hydraulic motor (going in and out) with battery back-up (in only). There is a second, break glass (and one each for the drencher and the vents) by the stage door.

 

I have heard that the Birmingham ICC has its safety curtain under automatic control.