Introduction to dry ice

[dwh]

Well, it's production time at my school again, and the teacher-come-director of this one has mentioned dry ice in her artistic visions (IMO completely unnecessary for the scene in question, but her vision is her vision)... I'm going to do a ring around a few companies around who I've been recommended to get the stuff from to get some more accurate prices and the like, but I've never really used it before, so was wondering if I could ask a few basic questions!

 

1) How quickly does the stuff get used up? As far as I know, she just wants to use it for the opening scene, which I would hazard a guess as being up to five minutes long, for a three-night run (also using it in a rehearsal or two the days before, no doubt), covering a roughly 6m by 6m area; how much would you estimate?

 

2) Storage? How long can we keep the stuff before it all sublimes (potentially explosively, if stored tightly, I would guess!)

 

3) Talking about using it for about 5 minutes, are we likely to need special extraction for it? I mean, it's carbon dioxide, so not particularly good for you, but are we talking about amounts that need serious consideration?

 

Obviously before any real planning takes place, we'll talk to our H&S officer, and a company or two to get it from (incidentally, can anyone recommend any near-ish Croydon; South London/North Surrey?), I'm just looking for a basic grounding in the stuff.

[bruce]

Searching thru the archives for "dry ice" produces 3 pages of results, including dry ice storage, dry ice - where and how much and plenty of others.....

 

Under no circumstances should it be stored in a sealed container.

[Ynot]

Daniel,

 

Sorry, but I'm going to play the usual card here.

Unless you are going to have experienced ADULT supervision, the use of dry ice is NOT recommended for schools.

The same problems apply to dry ice as to pyrotechnics and 'messing' with electrics. You are just not of a legal age to use hazardous substances.

CO2 is dangerous on a number of counts, and must be treated with respect.

 

OK - it's not as dangerous, maybe, as pyro/electrics, BUT there are enough potential hazards to make a potentially litigous argument should anything go wrong.

 

If I were you, I'd discuss this with your teacher-come-director and present the issues to her, along with the recommendations I've outlined.

 

Hazards include:

Dry ice can give cold-burns if in contact with skin;

If it gets in an eye it WILL cause blindness (eg if blocks are broken up and chips fly);

You need a proper fog machine (eg pea Souper) and these use very hot water;

There will be an amount of condensed seepage from the pea souper;

The ice needs to be kept in a suitable container;

 

Tony

[TomLyall]

Sorry, but I'm going to play the usual card here.

Unless you are going to have experienced ADULT supervision, the use of dry ice is NOT recommended for schools.

The same problems apply to dry ice as to pyrotechnics and 'messing' with electrics. You are just not of a legal age to use hazardous substances.

Tony, it's worth noting that in just over a month (and the show may well be after that), Daniel will be 18. With that in mind, lets strip your post to the critical bit, what you need is someone experienced in handling dry ice.

 

Unless you can find someone who has used it before who is willing to help, it might be worth looking into alternative effects, or as you suggest Daniel, drop the effect! It might be worth looking into low smoke machines, like the Jem Glaciator.

[danjshelton]

With the above hazards in mind, it might be worth adding that there are alternative methods that can be used to get a similar effect (Not as good as Dry Ice, But very close!). There's the Jem Glaciator X-Stream, that produces a ground hugging fog similar to dry ice. There are also other machines around from the usual effects manufacturers that do a similar job to the Glaciator (Just that I'm more familiar with the Glaciator so thought I would mention that one!).

 

Dan

[Stuart91]

As an alternative, you could consider using a low fogger. These use ice to chill the output from a normal smoke machine, so that it hugs the floor. Similar effect, and whilst I'm sure it's not as good as the real thing, it is a lot more practical and removes most of the H&S problems.

 

You should be able to find a hire company near you that has one. We have one, but are a bit too far away from you...

[Ynot]

Tony, it's worth noting that in just over a month (and the show may well be after that), Daniel will be 18. With that in mind, lets strip your post to the critical bit, what you need is someone experienced in handling dry ice.

Fair enough - though as a student still, that still may not be enough....

Unless you can find someone who has used it before who is willing to help, it might be worth looking into alternative effects, or as you suggest Daniel, drop the effect! It might be worth looking into low smoke machines, like the Jem Glaciator.

** laughs out loud ** - have you any idea how much those babies cost to hire?? Stage LX's basic price is £330! OK, you may get one for less elsewhere (though not by much) so I suspect a school is unlikely to go for a Glaciator, esp for a 5-minute effect!

 

You're right, though - there are options - both safer and sometimes cheaper, though not always the latter.

[pritch]

Before you get too involved with chasing up dry ice / low foggers, have you established that they definitely meant dry ice?

 

There are people out there who seem to use the terms dry ice and smoke interchangeably. It may well be that they said dry ice, when in actual fact the effect they're after can be achieved easily with a standard smoke machine.

[dwh]

Dry ice was definitely the intention.

 

Personally, I don't want to get involved with the stuff, or have any of my fellow students playing with it (I know it's not a friendly substance!), but the school have literally *just* (as in, this week) hired a new theatre technician; he hasn't started work yet (thus isn't around to talk to the director about effects and the like), but will be here before the production.

 

I'm still not sure about quantity (would it be fair to bank on 10kg per night? Would you say for 3-5 days, it's worth buying the lot in bulk and keeping it, or sorting out more than one delivery?), but thanks for your help so far!

 

Oh, and also, reading back on some old threads, fridges/freezers are mentioned... Surely they're fairly sealed containers?

[TomLyall]

Fair enough - though as a student still, that still may not be enough....

This might well be true, but it doesn't make any of the teachers suitable either. My point was simply that you need someone with proper experience or training in the use of dry ice.

 

** laughs out loud ** - have you any idea how much those babies cost to hire?? Stage LX's basic price is £330!

I certainly do, Tony. I've used both, and seen comparable quotes for both galcaitors and dry ice in the past. The dry ice option (including dry ice, delivery, storage, removal and a pea souper) came out more expensive than a Glaciator. This is especially true for longer runs if you require extra dry ice deliveries. Dry ice tends to have a much nicer effect though.

 

The glaciator is a lot safer. It can be DMX controled. It doesn't require an operator once switched on, unlike the dry ice that has to be supervised constantly and needs someone to operate it.

 

Tom

[Ynot]

Fair enough - though as a student still, that still may not be enough....

This might well be true, but it doesn't make any of the teachers suitable either. My point was simply that you need someone with proper experience or training in the use of dry ice.

Which, of course, was the crux of my initial point anyway...

** laughs out loud ** - have you any idea how much those babies cost to hire?? Stage LX's basic price is £330!

I certainly do, Tony. I've used both, and seen comparable quotes for both galcaitors and dry ice in the past. The dry ice option (including dry ice, delivery, storage, removal and a pea souper) came out more expensive than a Glaciator. This is especially true for longer runs if you require extra dry ice deliveries. Dry ice tends to have a much nicer effect though.

 

The glaciator is a lot safer. It can be DMX controled. It doesn't require an operator once switched on, unlike the dry ice that has to be supervised constantly and needs someone to operate it.

We had one (Glaciator) in last December - one of the panto companies hired for a week from a local theatre under refurb). The only way they could get the beast accomodated was under the stage feeding up thru the trap door in the floor. (We have rather restricted wing space, as I suspect do many schools etc!). I also had an ex-demo one on approval a couple of years back, and think we discussed it here why we didn't buy it. Too big, too noisy and even using different fluids our stage got too warm to keep the fog low enough before it disippated.

Dry ice, on the other hand, is actually cheaper - we have a local supplier and we can sort the means to store the stuff when needed, and have access to a couple of pea soupers already - and quite a few experienced foggers.

And yes - I MUCH prefer proper dry ice if we can sort it!

:)

 

Moderation: quotes fixed (properly this time!)

[Ike]

I tend to go for pellets rather than blocks/sheets as it makes life a hell of a lot easier, it does however sublime quicker in storage due to its larger surface area. A 5kg bag can be picked up for about £5 from lots of Universities, sand blasting companies and the like, if you have to go to BOC I seem to recall it being nearer £20. If you have somewhere close then buy some each day, if not you may have to buy in bulk in which case you will need to guesstimate how much to order. Remember a lot will have sublimed by the last night. If your going to transport it yourself you will need a van with a separate cab, never transport dry ice in the cab or passenger lifts etc.

 

You will need a suitable storage facility, a knackered chest freezer in a secure well ventilated area would do. Remember if the lid seals (eg. if it gets wet then freezes) the whole thing could explode so take care! You will want to prevent kids (or adults) getting their hands on it as there are a million and one very dangerous (yet fun) things you can do with it. Ventilation is also very impotent as not only can you end up suffocating due to oxygen depletion but even a relatively small increase in CO2 isn't particularly good for you over an extended period of time. CO2 will sink to low lying areas due to being denser than air so be careful of these danger areas. You will need to wear gloves, proper cryo ones are best but dry leather offers protection against brief accidental contact. Eye protection is a must, plastic face shields are much more comfortable and offer more protection than goggles just make sure its pulled right down.

 

Moderation: quotes fixed

Somehow I'm not sure they are! Moderation: Oops! re-fixed now.

[sparkyweb]

We are starting to find that the dry ice suppliers are becoming very careful who they supply dry ice to. In some instances, they have been known (I can only talk about the south-east here) to only sell dry ice to companies or account holders and they have refused to deal with individuals and schools.

[Jivemaster]

You will find the dry ice is cheap, however you will find its transport or couriering is NOT. If you find a local supplier start by estimating 2kilos a minute from a peasouper (remember they are electric 3K I think) and allow for about 5% of block CO2 to sublime daily inside a thermal chest (big foam poly box with lift off lid) 10kilos of CO2 will have little effect on the atmosphere in a theatre! The biggest prob will be keeping the draught down to keep the effect where you want it. (other than people wanting a bit to play with!)

 

Any good supplier should supply you with the MSDS for CO2(S)

[zonino]

We are starting to find that the dry ice suppliers are becoming very careful who they supply dry ice to. In some instances, they have been known (I can only talk about the south-east here) to only sell dry ice to companies or account holders and they have refused to deal with individuals and schools.

 

this is probably linked to the tightening up of chemical distribution, its probably a blanket policy across their entire chemical range (and you can do some funky chemical stuff with CO2(S) as well!)