# Dry Ice for Dummies!



## iandy (Sep 20, 2007)

Hey

I would like to use Dry ice in the next production I am doing, but I have very little knowledge of how Dry ice machines work and would really appreciate if someone could answer these few questions.

1. What would be an ideal machine for a black box studio (sorry haven't got measurements to hand), if possible between a 'Cumulus' and a 'Pea Souper' as that's what our local hire company offer.

2. How much does one machine hold of dry in Kg on average and how long would one container last say 60Kg of Dry Ice?

3. How does the Dry Ice need to be stored?

4. Are there any laws or Health and Safety issues I should know before using one.

Look forward to the replies.

Andy


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## Footer (Sep 20, 2007)

I would say go with a pea souper, they cover extremely well. As far as storing it goes, the key is to keep air out of it. I usually put it in a paper bag, seal that in a plastic bag, then put that whole thing into a well insulated cooler then duct tape the cooler shut.


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## BillESC (Sep 20, 2007)

Footer,

You are getting very close to creating a bomb. Dry ice expands as it sublimates. Enclosing it in a sealed enviroment can become explosive.

The best methods of dry ice storage are insulation. You can use moving blankets, sawdust, or any other media that keeps air away from the surface of the ice and creates an insulation field.


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## Footer (Sep 20, 2007)

BillESC said:


> Footer,
> You are getting very close to creating a bomb. Dry ice expands as it sublimates. Enclosing it in a sealed enviroment can become explosive.
> The best methods of dry ice storage are insulation. You can use moving blankets, sawdust, or any other media that keeps air away from the surface of the ice and creates an insulation field.



I do vent it, but at the same time I try to keep moving air from coming in and going out. Its sealed but can still breath. I usually just open up the little drain the the cooler, which seams to work.


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## gafftaper (Sep 20, 2007)

I'm going to be purchasing a LeMaitre Peasouper for my 55 square foot black box. Many of the dry ice machines you'll see are the size of a larger barrel or garbage can. So the Peasouper is nice because it's significantly smaller and lighter for storage. True it doesn't have the massive volume of one of the big ones but for our smaller spaces you don't need THAT much. According to the website Peasouper holds about 20 lbs of Dry Ice and lasts about 5 minutes. 

Safety is VERY important with Dry Ice. Dry ice "fog" is actually a cloud of (EDIT) *Carbon Dioxide*. (EDIT) *C02* is heavier than air so it will fill a low space and drive the oxygen out. So if you have a pit with an orchestra in it, dry ice fog will fill the pit and STAY there driving out all the oxygen... and killing your orchestra. Or if you have a LOT of dry ice fog pour into an audience same problem. Never let an actor hide, lay down, or pass out in a dry ice fog... as they may never get up again. 

As Bill mentioned be careful of sealing dry ice too tight, it is constantly giving off gas so it quickly can build up a lot of pressure... do a Youtube search for dry ice bombs to learn what not to do. (DON'T try it at home kids unless you like picking plastic shrapnel out of your face). For storage you want to insulate as much as possible while still allowing the dry ice to breathe. 

Finally you don't want to touch dry ice. It will give you these nasty little frost bite burns. So some heavy leather gloves are important to have around to handle it with (welding or cooking gloves would be great).


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## Van (Sep 20, 2007)

gafftaper said:


> .......................................................................
> Safety is VERY important with Dry Ice. Dry ice "fog" is actually a cloud of Nitrogen gas. .........................................


 
I Know you *really* meant to say Carbon Dioxide, But I thought I'd correct it for those in our audience who might not know.

What Gaff say is true, however. Carbon Dioxide gas is dangerous in high concentrations, for extended periods of time. 
As for you original questions, for a "typical" fog effect in, say, "A Christmas Carol" You could get by with as little as a Kg at a time. I have found it is best to rent your machine a few days early run some tests and figure out exactly how much you need for any given show. Then only get 2-3 shows worth at a time. That way you reduce the loss to sublimation. I've worked show where as little as 20 pounds was needed per 4 shows, and we kept it in a small styrofoam container, to some shows where we were getting it delivered 1.5 metre square pallets which would get us thropugh one night.


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## gafftaper (Sep 20, 2007)

Crap... it's been a long day with a set of sick 1 and 3 year olds... Let me just go edit that post.


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## jwl868 (Sep 21, 2007)

Metric units and English units mixed together in the answer - nice touch.

By the way, gafftaper, is the area of your black box correct? [At 55 square foot, I get about 7' x 8'...]

Joe


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## avkid (Sep 21, 2007)

jwl868 said:


> Metric units and English units mixed together in the answer - nice touch.
> By the way, gafftaper, is the area of your black box correct? [At 55 square foot, I get about 7' x 8'...]
> Joe


That's like the size of my basement office.
I might be able to fit six people in folding chairs if I tried.


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## gafftaper (Sep 21, 2007)

jwl868 said:


> Metric units and English units mixed together in the answer - nice touch.
> By the way, gafftaper, is the area of your black box correct? [At 55 square foot, I get about 7' x 8'...]
> Joe





Well the budget was running a little short and we had to cut somewhere and I wasn't willing to cut shop tools or lighting so overall building dimensions (and my math skills) were the first thing to go. 

Yeah That's it... That's the Ticket!


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## Van (Sep 21, 2007)

jwl868 said:


> Metric units and English units mixed together in the answer - nice touch.
> 
> By the way, gafftaper, is the area of your black box correct? [At 55 square foot, I get about 7' x 8'...]
> 
> Joe


 
Yeah, I'm Bi-dimensional.


Sure it's a small Blackbox, But think of the money he saves on Royalties, Lighting, Heating and Cooling, He can light the whole thing with a cliplight and cool it with a desk fan.


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## gafftaper (Sep 21, 2007)

Van said:


> Yeah, I'm Bi-dimensional.
> Sure it's a small Blackbox, But think of the money he saves on Royalties, Lighting, Heating and Cooling, He can light the whole thing with a cliplight and cool it with a desk fan.



Actually it's good thing that it's so easy to cool because with 196 dimmers, 60 S4's, 24 S4 PARS, and 48 Fresnels, it's going to get hot in there... I'm going to need a lot of side arms.


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## jwl868 (Sep 21, 2007)

It's so small you can only show The Hunchback of Notre Dame....

But seriously, I only pointed out the dimensions so that the original poster had a frame of reference.

Joe


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## iandy (Sep 21, 2007)

Thanks all the replies.

I measured the studio and its 36ft x 36ft. but use about 2/3 for stage and 1/3 audience. 

So the peasouper it seems to be! Basically we have a music and singing show and was hoping to use it for a about 2 or 3 numbers in the show each about an average song length (4mins) and we are having 3 shows and would like to test it out in dress rehearsal. 

So how much dry ice would I have to order for the peasouper do you think?

Also don't know if it makes a difference but im actually in London England as I have seen many of you are from US. 

Andy


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## gafftaper (Sep 21, 2007)

I think the biggest question is recharge time. You fill up the water, it heats up in the machine, drop in 20 pounds of ice and it lasts about 5 minutes. But then you have to reheat the water before you can fire it off again. The Lemaitre manual says it takes 45-60 minutes for the water to reach the proper temperature. I suppose you could drain the tank, and refill it with boiling water that you have standing by somewhere. I'm not familiar with the Cumulus (must be a British product) but, a little quick searching looks like it comes in two models one about the same capacity and one more than two and a half times the peasouper. Perhaps with the big one you could fill it up, run it 4 minutes, turn it off, wait, run it four minutes... repeat. Another website claims the Cumulus has "near continuous" operation, which I highly doubt. For maximum effect you need your water heated to near boiling, it would take an amazing heating system to keep the water warm enough to combat the chill of the dry ice for continuous operation. 

SO, I guess what I'm saying is to call your dealer and tell them you want three separate 5 minute bursts in the same show and find out if the one big Cumulus can handle that or if you need multiple foggers.


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## Logos (Sep 22, 2007)

When I was living in the UK (I left in 2003 and I now live in God's own country Australia) Dry Ice was really expensive and quite hard to get. I only used it about twice then went over to refrigerated low smoke machines. Check with LeMaitre about the supply of dry ice. You might be better off in London than I was out in the deepest wilds of Kent.


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## gafftaper (Sep 22, 2007)

Logos said:


> When I was living in the UK (I left in 2003 and I now live in God's own country Australia) Dry Ice was really expensive and quite hard to get. I only used it about twice then went over to refrigerated low smoke machines. Check with LeMaitre about the supply of dry ice. You might be better off in London than I was out in the deepest wilds of Kent.



You might also want to do a check of heinous crimes committed by one Tony "Logos" More in late 2002 or early 2003. It would be interesting to find out what got him banished.


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## Logos (Sep 23, 2007)

Moi? Banished? I had to sneak out under cover of darkness or they would never have let me leave.


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## David Ashton (Sep 24, 2007)

Sorry to be pedantic yet again but the statement that fog is carbon dioxide is not correct, the dry ice is the cold interface which condenses the water vapour from the boiling water into fog.It is water fog, it is wet, it will make the floor wet and instruments wet and amplifiers wet.While there is of course an increase in co2 levels I have never seen it effect anyone, so in a normal venue with basic ventilation there is not a problem, however there is a definite "getting wet" problem.


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## Van (Sep 24, 2007)

allthingstheatre said:


> Sorry to be pedantic yet again but the statement that fog is carbon dioxide is not correct, the dry ice is the cold interface which condenses the water vapour from the boiling water into fog.It is water fog, it is wet, it will make the floor wet and instruments wet and amplifiers wet.While there is of course an increase in co2 levels I have never seen it effect anyone, so in a normal venue with basic ventilation there is not a problem, however there is a definite "getting wet" problem.


 
The "Fog" itself is condensed water vapor or vapour, if you prefer. The agent for causing the condensation is Carbon dioxide gas, which, having recently sublimated form its solid form is extremely cold. While you are correct in saying that the "Fog" is not CO2, you are incorrect to imply that there is no CO2 in that Fog. It is the presence of cold CO2 gas that keeps the condensation condensed. 
You may never have personally seen it effect anyone, however there have been several cases of individuals who have passed out, waiting to make an entrance by crouching/laying in a thick cloud of "fog". It typically take an exposure to 20% or higher approximately 10-15 minutes to kill a human being, however exposure to concentrations of merely 10% can cause unconciousness, vomiting, and visual imparements is as little as a couple of minutes. Now will an actor, or muscian standing in the center of the stage expirience ill effects ? Most likely not. Will the Kid playing the ghost of Hamlets father, who is hiding behind a gravestone, waiting to make his appearence experience an increase in headaches, heart rate, difficulty breathing, it's quite possible.


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## David Ashton (Sep 24, 2007)

Dear Van co2 is soluble in water which it spontaneously interconverts between CO2 and H2CO3 so I really think it would be extremely difficult in practice to get close to dangerous levels especially in a theatre which has legal ventilation rules


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## jwl868 (Sep 24, 2007)

I don't have my chemistry books handy, but the weak acid nature of carbonic acid, not to mention the carbonate-bicarbonate equilibrium makes the "spontaneous" convertion of all the CO2 to carbonic acid highly unlikely. I doubt that a few percent of the CO2 is consumed that way. 

I'l have to check this more tomorrow.

(If that reaction was that extensive, they'd have solved the greenhouse gas problem with spray towers ages ago...)


Joe


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## gafftaper (Sep 24, 2007)

All I know is I've been told over and over by *many *different people stories about passed out actors, musicians in a pit, and even audience members as a result of too much dry ice fog. You are correct that under normal circumstance it isn't likely but it is possible and therefore something we should all be concerned about. If its a possible hazard then it is an important issue for everyone to be concerned about. Remember the actors and the audience are trusting you to keep them safe.


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## Van (Sep 25, 2007)

allthingstheatre said:


> Dear Van co2 is soluble in water which it spontaneously interconverts between CO2 and H2CO3 so I really think it would be extremely difficult in practice to get close to dangerous levels especially in a theatre which has legal ventilation rules


 
Simple test, Load up a pea souper, lie down in front of it completely immersed in the "harmless" water fog, Tell us how you feel after 5 minutes. 
While co2 is Soluble in water the reaction that occurs inside a fog machine is far from a 100% reaction. Most of the CO2 which dissolves into the water remains in the water in the fog machine itself. Take a sip, it's fizzy after running a fog cue. We tend to err on the side of caution here. As I view the safety and health of all personel working for and around me I will continue the policy of limiting peoples exposure to CO2 fog. For reference you might find the following useful;

Smoke and Fog Hazards

By Michael McCann, Ph.D., C.I.H.



Introduction

In the last 10 years, the use of fog and smoke to create
atmosphere or special lighting effects has greatly expanded, due
in great part to the influence of music videos.
There are a wide variety of products and machines used to
create smoke and fog effects, with varying degrees of hazard. 
This dadta sheete only discusses non-explosive materials that
depend upon a change in physical state to create the effect, not
a chemical reaction. 
Fog and smoke effects are created by generating a fine
mist, a dispersion of very small particles, or an actual smoke by
burning organic materials. All smokes and fogs are easily
inhaled. Some chemicals used to generate the smoke or fog are
toxic; however even chemicals that are not appreciably toxic can
be irritating to the lungs. In particular, high risk groups such
s people with asthma or other respiratory problems, children, or
elderly, and people having to do deep breathing (e.g a musician
playing a wind instrument or a singer) might be more susceptible
to inhalation of any material.
It is often difficult to obtain information on many of
these products, even from Material Safety Data Sheets (MSDSs),
because many manufacturers claim that the compositions are trade
secrets. Manufacturers of these products often make extravagant
claims as to safety. For example, many products state that the
chemicals used have been approved by the Food and Drug
Administration (FDA) for ingestion. However, the fact that it
might be safe by ingestion does not mean it is necessarily safe
by inhalation. 

Some manufacturers also claim that air sampling studies
indicate that the concentration of their product in air is below
the Occupational Safety and Health Administration's (OSHA)
Permissible Exposure Limit (PEL). This is very misleading, since
OSHA PELs and the Threshold Limit Values they are based upon are
intended to apply to workers in industry and do not usually
protect the general population, especially high risk groups as
discussed above. 

Many manufacturers have done acute toxicity studies on
their products. These animal studies only tell the effects of
single exposures and not of repeated exposures. In addition
these studies would not pick up reversible, respiratory
irritation which can be crucial to actors or singers. 
Another problem is determining the length of exposure. The
assumption is that these fogs are used only for short
periods of time. However in film production, for example, a
particular scene could be reshot many times, thus lengthening the
period of exposure. Also in theater, actors could be exposed
daily. In addition most theaters or motion picture productions
do not have an efficient method for clearing out the fog between
takes or scenes, so that there can be an accumulation of the fog
chemicals over a period of time. This can result in longer
exposures not only for the actors but also the crew.
In attempts to evaluate the safety of some of these fogs
and smokes, unions and other groups have had these products
analyzed. In addition, the National Institute for Occupational
Safety and Health (NIOSH) and others have conducted air sampling
studies to try and evaluate the safety of the products.

Hazards of Particular Fogs and Smokes

Dry Ice

Dry ice is one of the earliest types of materials used to
create fog effects. Dry ice is frozen carbon dioxide, and when
exposed to air it sublimes directly from a solid to a gas. The
cold gas causes moisture to condense into a thick, low-lying fog. 
Dry ice is the safest way to generate fog except in enclosed spaces where the carbon dioxide can accumulate and reduce the oxygen concentration in the air. This could cause
asphyxiation if the oxygen concentration falls below 19.5%. 
There would also be a hazard if someone was lying down in the dry
ice fog.

Petroleum Distillates
Many of the earlier types of fogs were based on kerosene,
fuel oil or other petroleum distillates. These were vaporized by
heating to generate a fine mist. Unfortunately inhalation of
these chemicals caused eye and respiratory irritation, chemical
pneumonia, and narcosis (dizziness, headaches, nausea, etc.). In
addition, the mist of these petroelum distillates is a fire
hazard. I definitely recommend against any fog product
containing fuel oil or other petroleum distillates.


Zinc Chloride Smoke Generating Devices

A number of companies sell smoke generators based on zinc
chloride (e.g. smoke cookies, smoke pots, smoke candles, smoke
bombs). Some of these also contain chlorinated hydrocarbons such
as perchloroethylene, a suspect carcinogen. The smoke is
generated by heating or burning the product, which is classified
as a Flammable Solid, D.O.S. by the Department of Transportation. 
These are available in sizes that generate small to very large
amounts of smoke. The Material Safety Data Sheets on many of
these products are not adequate and do not reflect their hazards. 
Use of these smoke devices in fire fighter training exercises has
resulted over the years in complaints of breathing problems,
chest paints, hot and cold flashes, headache, fever, fatigue,
sore throat, nausea, cough and even some fatalities. Some of
these symptoms might be due to chlorinated hydrocarbons, but most
are due to the generation of high concentrations of hydrochloric
acid from the reaction of the zinc chloride with water. In some
studies hydrochloric acid concnetration have been many times
higher than OSHA PELs and even approach levels considered
immmediately dangerous to life or health. Even lower levels of
smoke has caused symptoms. I recommend against the use of zinc
chloride smoke devices, or devices based on titanium chloride and
similar materials indoors or in outdoor situations where either
film crew or actors could be exposed to any substantial amount of
the smoke.


Ammonium Chloride

Ammonium chloride (sal ammoniac) is a common method of
generating smoke on stage and outdoors. The smoke is created by
heating the ammonium chloride. Air sampling studies have found
large concentrations of ammonium chloride, in some instances near
the OSHA PEL for nuisance dusts. Air sampling studies have also
shown that some decomposition of the ammonium chloride to
hydrogen chloride occurs during this heating. The hydrogen
chloride dissolves in water in the respiratory system to produce
hydrochloric acid, a respiratory irritant. The levels of
hydrochloric acid are much smaller than caused by the zinc
chloride smoke devices, but are still high enough to cause
concern. It is not recommended that ammonium chloride be used
indoors or in enclosed spaces.


Mineral Oil

This includes oil crackers and diffusion foggers. Oil
crackers involved bubbling air through a drum of mineral oil. 
The air bubbles reaching the surface contained "cracked" oil of
particle size 1 to 50 microns. This oil is not "cracked" in the
sense of chemically breaking down the oil but is merely creating
smaller droplet size. This has also been used in combination
with dry ice. The diffusion fogger produces a mineral mist of
less than 1 micron size by using a compressor to force mineral
oil through a series of fine filters. Air sampling studies by
CalOSHA in an enclosed sound stage 90'x75'x30' found that ten
minutes of fogging produced mineral oil concentrations for almost
2 hours that were 50% to 90% of the OSHA 8-hour PEL for mineral
oil. However this PEL for mineral oil is based on its use as a
cutting oil in industry; no toxicological studies have been made
on inhalation of mineral oil of particle size less than one
micron. However there is concern about long term problems such
as lipid pneumonia since the very fine mineral oil mist gets deep
into the lungs and stays there. This is not recommended for use
indoors or where personnel could inhale the mineral oil.


Glycol Fogs

During the last decade, a whole range of products have been
developed that use mixtures of water and polyfunctional alcohols,
including ethylene glycol, propylene glycol, diethylene glycol,
triethylene glycol, polyethylene glycol and glycerin. In general
these are safer than most of the other fogs and smokes with the
exception of dry ice. Ethylene glycol and diethylene glycol are
toxic by ingestion, causing kidney damage and possible death; the
other glycols mentioned are considered only slightly toxic. 
Ethylene glycol has been removed from most fogs after studies
showed that it is a teratogen (can cause birth defects). 
Unfortunately long-term studies have not been done on inhalation
of the mists of most of these glycols, although respiratory
irritation is sometimes listed on Material Safety Data Sheets. 
A more serious concern is how the fog is generated. These
mixtures are heated in a fog machine that heats the liquid to a
temperature near 600 F. One air sampling study found significant
levels of acrolein in the mist generated, about 20% of the OSHA
PEL. Acrolein is a strong respiratory and eye irritant. NIOSH
is conducting studies on various fogs to determine the extent of
this decomposition product. It is likely that some chemicals
could generate more decomposition products than others. 
Reformulation and finding ways to reduce the temperature needed
to create the mist are possible solutions. Despite these
problems, at this time the glycol fogs are probably the least
hazardous fogs to use, although some will probably turn out to be
safer than others.


Burning Orgnic Materials

The burning of gums such as olibanum gum (frankincense),
paper, and other materials can also generate smoke. These smokes
are irritating and considerable amounts of carbon monoxide may
also be generated. In addition to the smoke hazards, there is
the concern about the open flames. These materials should not be
burned inside or where people would be exposed to substantial
amounts of smoke.


Types of Respirators

The following table lists the types of respirators to use
with different mists and fogs:
Table 1. Respirator Selection for Smoke and Fog 

dry ice - none needed; test oxygen concentration in
enclosed spaces.

zinc chloride - acid gas cartridge and dusts and mist
filter; high concentrations need air- 
supplied respirators

ammonium chloride - acid gas cartridge and dusts and
mists filter

mineral oil - dusts and mists filter

glycol fogs - organic vapor cartrdige and dusts and mists
filter

burning materials - dusts and mists filter for smoke.


Recommendations

1. Smoke and fog on stage, television and motion picture sets is
regulated by most Fire Departments. In New York City, for
example, you need a fire permit to use smoke and fog just as you
do for pyrotechnics. 
2. All personnel (stage or camera crew, actors, etc.) should be
informed in advance of the intention to use smoke or fog and the
type to be used. Before use, there should be a discussion of the
hazards and precautions being taken. 
3. Obtain Material Safety Data Sheets on all smoke and fog
products. In particular note whether the Reactivity section
lists any hazardous decomposition products.
4. The choice of product depends on whether it will be used
indoors or outdoors, in enclosed spaces, and whether people will
be exposed for any significant period.
5. Children, elderly and people with respiratory problems should
be informed of their possible higher risks. A medical opinion
should be obtained as to whether they should be exposed.
6. Use only fog and smoke machines with the chemicals recommended
by the manufacturer. Other materials may clog, or otherwise
interfere with proper operation of the machine. Keep the fog
machine in good repair and use as instructed.
7. Use the minimum concentration of smoke for the minimum period
of time necessary. Avoid heavy concentrations when people are
exposed.
8. Only allow essential personnel on the set or stage when using
smoke and fog effects. Also evacuate any nearby areas where the
smoke could reach.
9. On stages, interior sets or in enclosed areas, the crew should
wear respirators. Respirators should also be available for
anyone wanting one in any situation. All respirators should be
NIOSH-approved. 
10. On stages, interior sets or in enclosed areas, rapidly
exhaust the smoke once not needed and between takes. Portable
ventilators of the type used in manholes can be used (e.g.
Coppus Engineering Corporation in Milbury, MA). In theaters it
is particularly important to exhaust the fog away from the
audience or orchestra pit. There have been situations where
children in the audience have gotten ill because of exposure to
fogs drifting from the stage. Outdoors, large fans can be used
to blow away the smoke. 
11. For motion picture production, minimize the number of takes
to further reduce exposure of personnel.
12. When burning organic materials, have a fire watch on hand. 

Sources of Additional Help
Written and telephone inquiries about hazards in the performing
arts and entertainment industries will be answered by the Art
Hazards Information Center of the Center for Safety in the Arts. 
The Information Center has a variety of written materials
available on this subject. Permission to reprint this data sheet
may be requested in writing from the Center. Enclose a self-
addressed, stamped envelope for our publications list. Write:
Center for Safety in the Arts, 5 Beekman Street, New York, N.Y. 
10038. Telephone: 212/227-6220

This data sheet has been made possible through funding from
the New York State Department of Labor, Occupational Safety and
Health Training and Education Program. CSA is also supported
with public funds from the National Endowment for the Arts, New
York State Council on the Arts and the New York City Department
of Cultural Affairs.

(c) Copyright Center for Safety in the Arts 1991


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## David Ashton (Sep 25, 2007)

Lots of words but still no facts, fog is essentially water vapour-fact.If it is dangerous please cite a case where a person was killed or hospitalized due to fog inhalation.I am completely open to learning facts about safety but the many myths around theatre need to be rebutted especially in a forum like this where myths and old wives tales become accepted as facts. just because something is written in a forum does not make it true and if people waste time and money protecting against imagined dangers that is wasteful.


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## icewolf08 (Sep 25, 2007)

Well, lets put it this way, a pound of dry ice is a fairly large quantity of frozen CO2. I don't know exactly how much O2 it would displace if it all sublimated, but I have to imagine that in a small space with less than adequate ventilation it could be a problem. Now, due to the nature of theatres, and building codes, even small black boxes probably have good enough ventilation to be able to use dry ice fog and not pose a threat to the audience or cast and crew. But, you probably don't really want to lay down in it for extended periods of time (especially if you are anywhere at high elevations like Salt Lake City, we have less O2 as it is...) By the same token, dry ice must be considered very safe as the AEA does not have any regulations on dry ice fog in their fog and haze guidelines.

I bet we have the case of multiple correct answers to some of the questions about dry ice fog. But, I am not going to personally test them (stick my head in it), and I doubt anyone else would, and test equipment is expensive. So basically it comes down to this: just be smart. All stereotypes have some roots in reality.


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## tenor_singer (Sep 25, 2007)

Here's a silly question...

My wife purchased a bowl (roughly 2.5 quarts... or liters) that has a small "sprayer" submerged in it.

When the sprayer is plugged in, it creates... mist... that looks exactly like the fog created by dry-ice foggers. I'm sure that some of you have seen them. They are often sold at novelty stores or shown at large lawn and garden shows as "meditation bowls". You can put smelling salts in them and some come with little lights turning the mist colors.

My question (after a rambling set-up)...

Do they make these in a huge stage size?


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## derekleffew (Sep 25, 2007)

tenor_singer said:


> My question (after a rambling set-up)...
> 
> Do they make these in a huge stage size?



Check out: 
http://www.meefog.com/special_effects/themed_entertainment.html#

http://www.fogco.com/mist.asp

Most involve too much plumbing for stage use; unless it is a permanent install. 

As an alternative to dry ice, consider LN2:
http://www.interesting-products.com/products.html

Happy Hazing!


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## gafftaper (Sep 25, 2007)

tenor_singer said:


> Here's a silly question...
> My wife purchased a bowl (roughly 2.5 quarts... or liters) that has a small "sprayer" submerged in it.
> When the sprayer is plugged in, it creates... mist... that looks exactly like the fog created by dry-ice foggers. I'm sure that some of you have seen them. They are often sold at novelty stores or shown at large lawn and garden shows as "meditation bowls". You can put smelling salts in them and some come with little lights turning the mist colors.
> My question (after a rambling set-up)...
> Do they make these in a huge stage size?



I've seen them used large scale in Vegas... I think it was the Star Trek Experience... or maybe it was the motion ride in the back of Caesars. Anyway, as Derek said yes it's possible and it looks good, but it's not practical for theater use... YET.


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## jwl868 (Sep 25, 2007)

One is, of course, welcome to be skeptical about any thing viewed to be “myth” or misinformation. But it takes a bit more than just hand-waving legitimate replies away. 

Facts:

- Only a very small amount of carbon dioxide will react with water to reach carbonic acid, carbonate, and bicarbonate. Very little will remain in solution as a dissolved gas. One can look up this information online at a university website – search for carbon dioxide solubility, or one can look the information up in a chemistry textbook.

- Carbon dioxide is denser than air. One can look that up in many chemistry texts.

- There are hazardous levels of carbon dioxide. One can find such references in USA OSHA and USA NIOSH.



But the unknowns in this topic include both how well the CO2 that is released is mixed and into what volume of air it is being mixed, and also is there any person that could be situated in a position for a period of time where such that adverse effects are experienced. When dealing with a potential hazard, one must make conservative assumptions, and even assume a worst case. Then one can determine an appropriate course of action to mitigate the affects or reduce the risks. But the task at hand is to identify the hazards involved in the improper handling of carbon dioxide.


To ignore the facts is to design-by-wishful-thinking.


Joe


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## gafftaper (Sep 25, 2007)

I just want to step back from the science argument and call for a bit of a safety check. 

You are responsible for the safety of the cast, crew, and audience. In any situation if there is the slightest POTENTIAL for danger it's your job to assess the situation and make a decision for the safety of everyone who are trusting you to keep the theater safe. It doesn't matter if we are talking about rigging, fire, electrical, shop equipment, or CO2... the rules are the same. Acknowledge the hazard potential, asses the danger for the particular show and theater, and make a plan for how to deal with it. 

Dry Ice is made of CO2 and the creation of Dry Ice fog involves the release of a lot of CO2 gas. It is dangerous to breathe too much CO2 and not enough O2... PERIOD. That's all you need to know. Is it a huge danger? Probably not in most situations. But that depends on the theater, the set, the amount of fog used and many other variables. For most of us assessing the situation and making a plan for safely dealing with CO2 fog means firing up the fogger as usual and not worrying about it. For some of us, maybe you need to put a fan in the pit to be sure that the orchestra has a source of fresh air coming in. For one show, you might have an actor who is supposed to lay in the fog and be hidden for 20 minutes before their shocking entry... you should be worried about that. Should you panic about working with CO2? NO. But don't ignore that there IS a POSSIBLE danger. 

The most dangerous thing in theater is people who have the mindset "it's not a big deal". Someone at "The Station" said... It's not a big deal if I don't use the fireproof soundproofing material. It's not a big deal if there's a little pyro in the show tonight. Its not a big deal if we build a wall here to limit the number of people who can get through the entryway at the same time. It's not a big deal if we pack a few more people in here. It's not a big deal if the emergency exit over behind the bar isn't clearly marked. 

Safety IS a big deal and any POSSIBLE danger, no matter how obscure or unlikely, needs to be assessed and dealt with carefully.


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## David Ashton (Sep 25, 2007)

Given that dry ice has been used all over the world for 100 years one would expect that someone might have died or been injured even telling an actor it could be dangerous could cause an effect, but nothing, like I said I'm open to persuasion but with absolutely no evidence of harm over such a long time I consider it to be totally safe.If some dry ice company would provide the dry ice I would have no qualms about being submerged in fog for 10 minutes.


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## avkid (Sep 25, 2007)

Frostbite is most certainly a danger, much the same as sitting in a bathtub full of ice is a bad idea.


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## Van (Sep 26, 2007)

allthingstheatre said:


> Given that dry ice has been used all over the world for 100 years one would expect that someone might have died or been injured even telling an actor it could be dangerous could cause an effect, but nothing, like I said I'm open to persuasion but with absolutely no evidence of harm over such a long time I consider it to be totally safe.If some dry ice company would provide the dry ice I would have no qualms about being submerged in fog for 10 minutes.


 
I'll try one more time;

From the Chicago Artists resource website http://staging.chicagoartistsresource.org/?q=node/14986

*Fog and Smoke: Part Two*

_By Michael McCann, Ph.D., C.I.H._ 
This second part in the series on fog and smoke will discuss the hazards of particular types of fog and smoke.

From "City Theatrical"s website. One of the Leading manufacturerers of Dry-ice based fogging systems.
http://www.citytheatrical.com/



*SAFETY BULLETIN* 
[FONT=helvetica,arial]*DRY ICE SAFETY*[/FONT]

*1.* Read the "Material Safety Data Sheet" for Carbon Dioxide, the Compressed Gas Association "Guidelines for Oxygen Deficient Atmospheres" and the *ESTA* "Guide to Modern Atmospheric Effects". 
*2.* Dry ice is extremely cold, -109 degrees F (-78 degrees C). Avoid contact with skin and eyes; use gloves and safety glasses in handling. Do not ingest. Keep away from children. 
*3.* Dry ice expands as it changes from a solid to a gas. Do not keep in stoppered or tightly closed containers. Store in a safe place away from people. Be sure storage area has adequate ventilation. 
*4.* Dry ice is the solid form of carbon dioxide. Carbon dioxide is 1.5 times as heavy as air and can collect in low lying areas. Carbon dioxide can cause asphyxiation due to lack of oxygen, and in sufficient concentrations is toxic. *Never lay down in dry ice fog or any other fog. *Always provide adequate ventilation to low lying areas such as basements, trap rooms, and orchestra pits. Provide adequate ventilation in automobiles during transport. 
*5.* People walking in dry ice fog must be instructed to be aware of stairs, obstructions, openings in the stage, etc., which may be obscured by thick fog. Be careful of water vapor condensing on the stage floor. *SAFETY BULLETIN* 
Compressed Gas Association, Inc. 
1725 Jefferson Davis Hwy. Arlington, VA 222024100
(703)979-0900/(703)979-0134 
*OXYGEN-DEFICIENT ATMOSPHERES (LESS THAN 19.5%)*
The normal oxygen content of air is 20.9%. Depletion of oxygen content in air, either by combustion or displacement with inert gas, is a potential hazard personnel throughout industry. A general indication of what can potentially occur relative to the percentage of oxygen available is given in the table below. 
Note: These indications are for a healthy average person at rest. Factors such as individual health(e.g., Smoker), degree of physical exertion, and high altitudes can affect these symptoms and the oxygen levels at which they occur. 
Oxygen Content Effects and Symptoms of acute exposure(at Atmospheric Pressure) % by Volume) 15-19% Decreased ability to perform tasks. May impair coordination and may induce early symptoms in persons with heart, lung, or circulatory problems. 12-15% Breathing increases, especially in exertion. Pulse up. Impaired coordination, perception, and judgment. 10-12% Breathing further increases in rate and depth, poor coordination and judgment, lips slightly blue. 8-10% Mental failure, fainting, unconsciousness, ashen face, blueness of lips, nausea(upset stomach), and vomiting. 6-8% Eight minutes, may be fatal in 50 to 100% of cases; 6 minutes, may be fatal in 25 to 50% of cases; 4-5 minutes, recovery with treatment. 4-6% Coma in 40 seconds, followed by convulsions, breathing failure, death. *WARNING: *Exposure to atmospheres containing 8-10% or less oxygen will bring about unconsciousness without warning and so quickly that the individuals cannot help or protect themselves. Lack of sufficient oxygen may cause serious injury or death. 
When personnel are subjected to, and around, oxygen-deficient atmospheres, there are certain considerations which are as follows: 
1. Never enter a suspected oxygen-deficient atmosphere without proper protective breathing apparatus and attendant support. 2. Analyze the atmosphere to determine if there is a deficiency of oxygen. Continue to monitor during the work process. If oxygen level is less than 19.5%, ventilate to establish good air quality. 3. Train the worker on what to expect and how to handle it. 4. Blank (positively isolate) any incoming lines to a confined area and ventilate the area. 5. When it is necessary to work in any oxygen-deficient atmosphere, provide self-contained breathing apparatus or breathing airline mask for all workers. 6. An established hazardous work permit procedure should be used in all confined space activities. This bulletin is intended to give a general overview of a potentially dangerous situation. For more detailed methods of dealing with oxygen-deficent atmospheres please see CGA Pamphlet P-14-1992, Accident Prevention in Oxygen-Enriched and O Oxygen-Deficent Atmospheres. _***********CGA GRANTS PERMISSION TO REPRODUCE THIS SAFTEY BULLETIN*********** *_
*Dry Ice*
Dry ice is one of the earliest types of materials used to create fog effects. Dry ice is frozen carbon dioxide, and when exposed to air it sublimes directly from a solid to a gas. The cold gas causes moisture to condense into a thick, low-lying fog. 
Dry ice is the safest way to generate fog, except in enclosed spaces where the carbon dioxide can accumulate and reduce the oxygen concentration in the air. This could cause asphyxiation if the oxygen concentration falls below 19.5%. There would also be a hazard if someone was lying down in the dry ice fog.

ESTA 's Monitoring of Carbon Dioxide http://www.esta.org/tsp/safety/docs/foginfo/How_to_Monitor_Carbon_Dioxide.pdf

And last but not least, Apocryphal as it may be an excerpt from Ned Bowmans Intergalactic Cookbok website. http://www.scenographicmedia.com/Atmos.htm#atmos_SFC_FogMachine

_DRY ICE FOG EFFECTS. Because carbon dioxide is so intimately a part of our lives, indeed we spend our whole lives producing it, there is a tendency towards careless handling of this gas in performing arts situations. Regard the paramecium, for whom the single greatest hazard in life is being smothered in his own carbon dioxide! CO2 gas is heavier than air, and will displace oxygen-laden air from the lowest volume in your production space as it is liberated. Example: a Mexican theatre production in the '70's was planned to opened with actors who emerged from a steaming "cauldron" through a blanket of CO2 fog. While waiting for cues to rise through the gas, they were overcome by the concentrated CO2 in the space completely open overhead. Example: a very well-known Broadway musical in the '80's used very large quantities of a mixture of glycol/water and CO2 smoke for a curtain effect. A technician in the traps area became light-headed nightly from the effect of CO2 being trapped in the pit area of the theatre which was effectively a large, un-ventilated vat (it had previously been a swimming tank). _


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## David Ashton (Sep 26, 2007)

Oh well that livened up this little thread.


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## thelightingmancan (Oct 5, 2007)

you had asked about laws, the only one is that you must be 18 years old to purchase it


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## Dalamar (Aug 12, 2009)

gafftaper said:


> Safety is VERY important with Dry Ice. Dry ice "fog" is actually a cloud of (EDIT) *Carbon Dioxide*. (EDIT) *C02* is heavier than air so it will fill a low space and drive the oxygen out. So if you have a pit with an orchestra in it, dry ice fog will fill the pit and STAY there driving out all the oxygen... and killing your orchestra. Or if you have a LOT of dry ice fog pour into an audience same problem. Never let an actor hide, lay down, or pass out in a dry ice fog... as they may never get up again.


 

The symptoms related to CO2 poisoning are usually due to the other contaminants in the air that also build up as a result of insufficient ventilation. However, at high levels, the carbon dioxide itself can cause headache, dizziness, nausea and other symptoms. This could occur when exposed to levels above 5,000 ppm for many hours. At even higher levels of CO2 can cause asphyxiation as it replaces oxygen in the blood--exposure to concentrations around 40,000 ppm is immediately dangerous to life and health. CO2 poisoning, however, is very rare. 

In other words, if your orchestra starts being dizzy, throwing up and fainting, it's time you turned off your machine. 

I'm just pointing this out because I believe just like all of you who posted here that responsible usage is paramount and, forgive my bluntness, but disregarding the simple common sense rules stated in this post is nothing but plainly dumb and on the fringe of criminal negligence... 

I, for one, applaud all whom have contributed to this post. 


You may want to check this machine out, which can operate either with L-Co2 or L-N2, without dry ice and with a controlled effect. It's available for hire in London through several outlets; I'd try White Light:

http://www.mdgfog.com/pdf/ice-fog-series_e.pdf



ww


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