Dry ice

[Ynot]

In the back of my mind I thought an accident happened with an orchestra. the dry ice rolled off the stage into the lowest point and some of the band were hurt, I think HSE got involved that time

To be honest, I'd say that would probably be an urban myth.

 

As has already been pointed out the actual fog produced is a mixture of CO2, moisture and regular air, and hughly unlikely to be anywhere near serious danger levels by the time it's travelled across a stage and down into a pit.

 

From my actual experience, I recall about 25 years ago sitting as a punter for a local show on an amateur stage where they had a serious amount of ice left over for the final night, so went a little bonkers with the preset fog effect. The CO2 was pumped in from a LARGE custom built souper and must have been over 8 or 10 feet deep by the time the house curtain was raised. The fog literally hung like a wall of white for several seconds before suddenly dropping off the stage front into the fully manned pit. They manfully played on through the fog and it dispersed quite quickly and to my knowledge noone suffered any ill effects.

 

Yes - we MUST stress the safety aspects of any risky practices we use, and yes we MUST continue to maintain that if you don't KNOW how to handle stuff like this, then get a man in who can. But we must also be wary of scaremongering where there really is no need.

[sleah]

Sorry, I can't really add anything constructive....

 

I've only had a teeny little experience with dry ice, but lots of experience with haze/fog in a club/disco environment and bit in theatre.

 

Do people find the response to dry ice the same as that to fog? i.e. suddenly people develope asthma or shortness of breath and complain they can't breath, when in fact it's all in the head?

In other words, you roll out the dry ice effect and half the audience immediately starts coughing like old smokers despite the effect being no where near them?

[Habu]

Sorry, I can't really add anything constructive....

 

I've only had a teeny little experience with dry ice, but lots of experience with haze/fog in a club/disco environment and bit in theatre.

 

Do people find the response to dry ice the same as that to fog? i.e. suddenly people develope asthma or shortness of breath and complain they can't breath, when in fact it's all in the head?

In other words, you roll out the dry ice effect and half the audience immediately starts coughing like old smokers despite the effect being no where near them?

 

 

If I fill the stage with haze during blackout, nobody is coughing. When the lights come on and people see the haze, somebody starts coughing. Lights go off, coughing stops. Same with dry ice. It's all in the head.

 

 

We use Unique 2.1 hazer and only thing it causes is that dries your throat. And you can fix it by taking a glass of water. Some singers complain about haze that it makes singing harder (if I sing, I dont notice anything difference in my voice with/without haze). Now they can say that we can't use haze. Good thing is that they say this before we do anything so we don't do anything special that requires haze. Just normal wall washes. Beam effects are useless without haze. They have surely noticed that we don't do anything special when they perform because we can't use haze. I wonder if they someday let us use haze B-)

 

I have asthma and have never felt that smoke/haze irritates me. Only dry throat but it's not problem (it can be caused by many other factors too!). This is worth of reading http://actorsequity....finalreport.pdf

 

Sorry my english

[whitehousejamie]

Thank you everyone for taking the time to respond, very helpful :)

[David Ripley]

Nick is right

 

There was an accident in the West End, Grease I think, when a technician either understage or in the pit was made unconscious due to dry ice

 

Detectors were fitted and I believe the company were prosecuted by the HSE

 

It was a fair few years ago but did happen

 

David

[paulears]

Nothing on the HSE website, do you have a link?

[David Ripley]

Nothing on the HSE website, do you have a link?

 

It is on the ABTT website under Technical Resources/Safety Matters. There is a link to a PDF quoted below

 

Dry Ice

 

When a Dry Ice Machine was operated on stage during a preview performance of a popular musical -

carbon dioxide (CO2), being heavier than air, seeped into the pit. A member of the theatre staff who was

in the orchestra pit became disorientated and collapsed. The member of staff was taken to hospital and

later released, fortunately without suffering any apparent long-term injury.

 

HSE prosecuted the producer on two counts:

1. Under COSHH exposing a person to Carbon Dioxide fumes.

 

11. Health and Safety at Work, Failure to asses the risk.

 

Fines were imposed amounting to £4000,

 

The use of Dry Ice comes under the COSHH regulations which came into force on 1st October 1989,

applying to all work activities where hazardous substances are used. COSHH Regulations (now forming

part of the Health and Safety at Work Regulations) involve all employees, HOD's and Theatre Managers

in an assessment to prevent a health risk that may arise from a substance 'Hazardous to Health'.

These machines are used extensively in Pop Concerts, Ballet and Pantomime. This accident highlights

the problems associated with such effects and the need for technicians to be aware of the associated

problems.

 

Solid carbon dioxide is immersed into hot water and the resulting vapour is usually directed by a fan and

ducting across the stage. Often the dry ice is purchased in pellet form or solid blocks and when broken up

into smaller pieces allows a more rapid vaporisation which increases the dry ice effect.

 

The effect produces a solid white cloud mist over the stage. Carbon dioxide does not support life. CO2 is

heavier than air and can exclude the oxygen in the air by flowing into low-lying confined spaces; anyone

breathing in these conditions for only a short time, will at best become drowsy and at worst is liable to

suffocation.

 

A number of points need to be observed:

 

1. It is important that everyone on stage should be aware of the dangers of CO2 and know when the dry

ice machine is to be operated. Operation of the machine should take into account safety of the staff,

performers and audience. Vapour outlets should be in sight of the operator at all times.

2. Rehearsal of the effect must be carried out to determine the direction of flow of the dry ice vapour and

people coming into contact with it. Precautions must be observed if dry ice vapour falls into the orchestra

pit or flows into areas such as basements, under stage storage or the auditorium. Care needs to be taken

to move the machine to a new location or redirect ducting. The amount of Dry Ice should be limited to the

minimum necessary to create the desired effect.

3. Good ventilation is important - as the vapour becomes invisible the gas concentration may become

difficult to determine. Health and Safety recommend that if there is any 'doubt about the concentration

present, expert advice should be sought to monitor the oxygen and carbon dioxide levels before the

equipment is used'.1

 

1 Guide to Health, Safety and Welfare at Pop Concerts and Similar Events.

As I say, my recollection is that it was on Grease at the Dominion, which makes it a mid 90's incident

 

David

[ImagineerTom]

It's niggling away at the back of my memory, I'm sure I remember it being at the Dominion theatre so that would tally with the thought it was Grease

[paulears]

That's useful info, thanks for that. I wonder why a search on the HSE site doesn't pick up anything other than industrial incidents with gases.

Paul

[whitehousejamie]

Thank you for the additional replies. If anyone would be kind enough to send me any guidance in order to carry out a Risk Assessment it would be much appreciated.

[Nicktaylor]

I would approach your local council. All the RAs in the world wont help if they wont allow use in the venue. I would have thought someone in the council setup could help you. It maybe the majority of councils dont care but there are some who are much stricter because of some previous incident?

[paulears]

If you need a generic dry ice risk assessment form - I've got one here.

 

It may get you going.

[whitehousejamie]

Thanks Nick, and Paul for providing a link to the RA, much appreciated.

 

After a bit of thought we decided to buy an ex-hire machine (10 out of 10 has sorted me out with a good deal, thanks Paul!) as I will probably incorporate the effect into future shows.

 

We will be spending some time assessing all the risks involved before the first use, the one thing that crossed my mind relates to scenarios such as first dances at weddings. More often than not there will be children in attendance at the event. How would you go about minimising the risk to them? Make announcements to parents to ensure children are not crawling around on the floor during use? Would this be considered a sufficient precautionary measure?

 

Apologies for all the questions.

 

Many thanks

[ImagineerTom]

You could make the announcement but they wouldn't be listened to.

 

Broadly speaking there's no risk from short-term exposure to the "smoke" in normal use so provided you're only using it for one or two songs at a time I wouldn't see a need to make any announcement and would deal with the risk simply by keeping an eye on the dance floor - if you see any kids suddenly collapsing then do something about it.

 

The risks relate to the CO2 "pooling" in low areas (eg orchestra pits, sub stage stairwells) in large quantities thus displacing oxygen; from memory the problem we were talking about above related to a show that was pumping huge quantities of dry-ice smoke down the stage (and thus in to the un-ventilated pit) for prolonged periods twice a day; none of these would strike me as situations likely to occur at the average wedding so generally my risk reduction action would be to simply to do a quick survey of the location to ensure there's not anywhere it's likely to pool with CO2 and to keep an eye on the whole area when it's in use so that if someone does have a problem you can send help. Asphyxiation isn't instant death; you've got a whole load of feeling dizzy and falling over first which you should be able to spot if it is happening and cure simply by moving the victim to somewhere with a more normal air mix.