Antiviral fog could get concerts and theatres going again?

[alistermorton]

TBH I'd have thought that, given the potential of UV injury, a full interlock system like that for x-ray rooms is not excessive.

[p.k.roberts]

Unless I'm missing something here (very possible) surely any kind of UV 'sterilisation' could only be effective if there are no shadowed areas. I can't see how that would really be practical in an auditorium. I'd even be sceptical about this kind of device which I just happened upon ....

 

https://www.thomann.de/gb/micker_pro_mikrofon_sterilisator_uvs_01.htm

[Brian]

Unless I'm much mistaken, germicidal lamps are normally used at relatively close distances. With them mounted on the ceiling of the auditorium they going going to need to be the mother of all lamps to get sufficient UVC down where it's needed. And how many auditoriums have sufficient mounting points to overcome any shadowing?

[adam2]

TBH I'd have thought that, given the potential of UV injury, a full interlock system like that for x-ray rooms is not excessive.

 

Less dangerous than X rays, so precautions could be slightly less strict.

 

Presence detection that latches off, NOT self resetting. And a time switch. And perhaps warning strobe lights.

 

 

 

 

 

[Jivemaster]

A very good and much safer use for UV sanitising lamps is building them into a air handling plenum, this way the recirculating air is sanitised but the UV lamp is inside a (UV blocking) metal can.

 

Both UV and ozone will sanitise, both have hazards and both can damage the softer and polymer parts of the decoration.

[adam2]

Unless I'm much mistaken, germicidal lamps are normally used at relatively close distances. With them mounted on the ceiling of the auditorium they going going to need to be the mother of all lamps to get sufficient UVC down where it's needed. And how many auditoriums have sufficient mounting points to overcome any shadowing?

 

The higher wattage germicidal lamps work fine at several meters mounting height, a prolonged exposure makes up for a low intensity.There used to be a design of fitting that used a pair of 36 watt lamps, intended to be wall mounted and pivoted. Lit 24/7 and directed upwards during working hours, and downwards outside of working hours. Manually adjusted by a pole with hook on the end. The person doing the adjusting would be briefly exposed, as would be any night watchman or fire patrol, but no one worried back in the day.

 

Shadowing would be a problem, so germicidal lamps are NOT a cure all but are a relatively cheap "extra line of defence"

 

In the USA, d0m3stic clothes dryers often contain a small germicidal lamp to sterilise the laundry as it dries. A precaution unknown d0m3stically in the UK, though some industrial or coin-op dryers do contain such lamps.

 

I am only aware of one accident involving these lamps, and that was deliberate misuse rather than a true accident.

Edited June 25, 2020 by adam2

[Bryson]

I just had a moderately long conversation with a distributor of these UV-C products. Theirs, once the safety is tripped (ie: the PIR) they will not re-energize until the whole fixture is reset. So, indeed, they Latch off to prevent the "sleeping person" scenario.

 

They also recommend the use of timer switches to only apply power in the early hours of the morning, or when manually overridden. (eg: clear the auditorium between shows and manually "blast" it.)

 

One thing to watch out for is rooms like control rooms that are not a part of the auditorium, technically, but have windows into it. Any kind of interlock would need to take that into account. I'm not sure what, if any UV-C attenuation is offered by regular glass.

 

 

The units I was looking at are good for about 40M2 each, with about a 100 degree "beam", so probably OK to be mounted at 6 metres and permitted to overlap each other to reach the required dose. (That also helps with the shadowing problem.) Auditoria with finished ceiling might have a challenge but I could see them working in an "exposed services and catwalks" kind of room. One other thing to watch is the maximum effective range of the movement sensors they come equipped with.

 

 

Cost was comparable to mid-range fixed LED fixtures, around $1000-$2000 / fixture. (That's about 600 -1200 quid in old money. ;))

 

 

However, one big unknown: How they interact with the fabrics they will be shining on. We all know how bad sun-bleached theatrical drapes get - so a big concern for me would be the longevity of the seats / drapes in the treated area.

[sandall]

Shadowing would be a problem...….

It's one thing meeting chewing-gum on the underside of your seat or armrest...……………….:(

[Ynot]

Surely the point that's the problem with ANY method of decontamination of an auditorium (or any space for that matter) is that no matter how good the clean-up is, as soon as you let a house of punters in to their seats, you have the potential for an asymptomatic carrier to bring the virus in with them and infect those in the vicinity...?

 

Let's just remember that it (presumably) only took a small number of people to enter the country to start this pandemic off.

All of the work that's going into cleansing places and distancing etc will mean nothing if we just let large groups of people gather in very close proximity in an exposed place. Forget the potential for transmission on the beaches (which tbf is bad enough) -sitting punters in any sort of clusters in a big enclosed space with A/C circulating their exhalations around the place has GOT to be one of the biggest potentials for infecting others...

 

It's far from good, but even as a venue manager I'm being VERY cautious about any moves to re-open the doors - we can't survive on 20 to 30% capacity, and even 50%+ is in the region of too risky in my eyes....

[dbuckley]

One certain way to safely interlock suck dangerous lamps would be to interlock them to the alarm system.

 

In our little (50 seat) theatre, when the alarm is armed, all non-essential power to the whole building is killed, which means no worrying about a heater left on in the dressing room...

[bigclive]

The theatre industry has been using the ultimate UVC lamp for decades. The 400W UVA one with the dark Wood's glass envelope.

 

It's interesting to note that the 400W blacklight lamps are very inefficient compared to the phosphor coated fluorescent tube version, as they merely filter out the weak UVA peak and the strong UVC peak that normally gets converted to UVA by the phosphor gets blacked out.

 

The point the 400W lamps become the ultimate germicidal lamp is when the outer glass gets broken, revealing the quartz tube inside.

 

I have a very odd mercury lamp here from a very old cinema. It has the bare quartz tube inside a clear glass sleeve. I'm not sure what its original purpose was. I've not powered it, so it may be a UVC auditorium sterilisation lamp or just an early UV lamp with strong blue output.

[adam2]

UV black light lamps are NOT effective against viruses and bacteria. These lamps which are black or deep violet in colour when not lit produce near ultraviolet light only just beyond the visible range. They have many uses in the entertainment industry as they cause fluorescent pigments to glow. Also used to detect forged banknotes, altered documents, urine stains, and hidden laundry marks on hotel linens.

 

If used with common sense, blacklight lamps are reasonably safe, but they are NOT effective against viruses, or bacteria.

 

To kill viruses and other nasties, germicidal lamps are needed, and preferably ones of reputable brand and obtained direct from a recognised UK based lamp wholesaler.

 

 

 

[Stuart91]

In our little (50 seat) theatre, when the alarm is armed, all non-essential power to the whole building is killed, which means no worrying about a heater left on in the dressing room...

 

That's quite clever. I've done something similar, where the lights in all the ancillary areas in our warehouse are "slaved" via contactors to the main switch on the way in. I thought about controlling some outlets in a similar way (to avoid the "heater left on" scenario, but it's hard to work out what's essential and what isn't, a socket that has a heater in one day will have a PC rendering something the next.

 

 

What might work well for dangerous sterilising lamps is set up the interlocks so that they are only powered when the alarm is armed, but get cut when the alarm goes off. Hopefully anyone wandering around will trip a PIR and set the alarm off before sustaining too much harm. (I'm thinking of the sort of scenario where a drunk passes out in a dark corner and comes to after the building is closed. Very rare, but it does happen. Plus you don't harm any intruders or firefighters)

[themadhippy]

UV black light lamps are NOT effective against viruses and bacteria

erm did you miss

The point the 400W lamps become the ultimate germicidal lamp is when the outer glass gets broken, revealing the quartz tube inside.

[musht]

Ozone generators used to be a feature of air conditioning, clean up the recirced air. Ozone starts smelling at some tiny quantity in PPM, bit of an irritant that will eat most synthetic materials,

 

Power density and shadowing make UV sterilising large areas look more like cleaning theatre than actually cleaning the theatre....