Safety FAQ

Started by stuwaudby, April 20, 2010, 02:22:27 PM

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stuwaudby

Workshop and Gas Safety FAQ Version 1.2, 29 December 2011

This data sheet is intended to provide technical and safety guidance for the equipment and hazards involved in glass bead making. Safety is a fine balance of risk and speed (or convienience) which needs to be assessed by a home user. For a business user the balance of risk and speed is governed by various laws and less open to interpretation. This tutorial is intended for the home / personal user so I have tried to provide sufficient information for you to be able to understand and make your own mind up about your personal safety and the safety of others.

Fire Ignition Risk

Working with high temperature naked flames and glass is obviously a fire risk. It should not pose a threat to life because the source of ignition is attended while you are working and can be dealt with before it becomes dangerous. There are two ways to mitigate fire risk, passive and reactive. Passive means preventing the ignition in the first place, for example removing any combustible material from your workspace. Reactive prevention is the means to deal with a fire before it becomes hazardous. You will need to have the equipment to hand to be able to deal with it quickly. Think about the following:

NEVER leave a lit torch unattended.
What combustable materials are in the vicintity of your torch?
Is your torch fixed to the worktop, could it fall off when lit?
Could molten glass drop onto your gas or oxygen pipe?
What else could hot glass drop onto? Is your floor wood? or carpeted?
Could anything fall into your work space?
Is your chair fire certified?
Do you store any flamable liquids or material near to your workspace?
Get a metal emergency bucket - very useful for emergency disposal of hot things and non flammable waste.
Do not have a waste paper bin anywhere near where you work.
Do you have a fire extinguisher? Can you reach it without putting yourself in more danger?
Can you switch off your electrical equipment without reaching over them?
Do you have smoke alarms, are they located between sources of fire and your bedroom? Is one located in your escape route?

The less combustible material in your workshop room the longer you will have to dowse a fire or escape. Fire in a house spreads very quickly, if curtains or furnishings catch you will have less than 30 seconds to escape before the heat and smoke poses a serious threat to life.

Fire Consequence

If the worst happens and something catches fire what will you do?

You should have two distinct plans: What can be immediately done to stop the fire spreading and an Evacuation plan for your house. If fire breaks out you have very little time to react. You will not have time to goto the kitchen, fill the kettle and run back with water. You could have a life threatening fire within 20 seconds.

BUY A FIRE EXTINGUISHER. A decent extinguisher is about £40, will last many years and could save your house. There is no excuse not to have one. The extinguisher should be located on the route to the exit so you have an escape route when you use it. An extinguisher is unlikely to have an impact on anything bigger than a paper bin fire. Even after an extinguisher has been used the heat can cause the fire to re-start. Second best to an extinguisher is a bucket of water but do not use it near electricity. You will not have time to fill it before a fire becomes uncontrollable.

There are three types of fire extinguisher available, each will help but all have their drawbacks:

1. Dry Powder is the most commonly sold domestic extinguisher. It knocks out flame but does not remove heat. It is useless on any established domestic fire but can knock down a small fire if used quickly. Safe to use in all circumstances. Makes a big powdery mess when used.
2. Carbon Dioxide is harder to get hold of and much more expensive. It is better than powder because it can penetrate confined spaces and does not cause any damage. Could cause asphyixiation in a confined space. It is heaver and thefore harder to manhandle and use.
3. Water propelled by gas has the advantage of cooling a fire but is dangerous to use anywhere where mains electricity is present.

The biggest fire risk in your house is probably not you workshop. A fire in your workshop is likely to be noticed and responded to immediately. The fires which kill are those that start in the night while you are sleeping. Do you leave electrical equipment powered over night in your house?

Every house should have an evacuation plan. Before you move onto the next section of this FAQ please commit to making your own plan and communicating it to all your family and having a practice. You should consider the following:

What are your fire escape routes?
Does everyone know the routes they can safely escape through?
Are any of the routes locked?
How many babies are in the property, are there enough adults to get them out without return trips.
Are your bedroom windows locked? Can you escape through the window without breaking glass?
Will you break bones if you have to jump?
Does your family know exactly what to do in the event of a fire? Do they know the escape routes? Do you have a plan? Have you ever practiced?
If you have children and they do not know what to do they are likley to come to your bedroom or hide, make sure they know what to do.
Do you have smoke alarms?
Is the smoke alarm positioned along your escape route?
Do you have a fire extinguisher? Is it located near an exit?
When was your house last re-wired?
When were your electrics last inspected?
Do you have any faulty electrical equipment?
Is any of your electrical equipment so old it could have built up dust internally?

Asphixiation / Gas Poisioning

Combustion of propane (mapp or butane) and oxygen results in the production of mainly carbon dioxide and carbon monoxide. A neutral or oxidinsing flame will produce mainly carbon dioxide. A gas rich reducing flame will produce some carbon monoxide. There is a significant difference in hazard.

Increased levels of Carbon dioxide will make you feel sleepy, dizzy, out of breath and could reult in a headache. If you get any of these symptoms then get some fresh air immediatly. Carbon dioxide is not poisonous but can kill by displacing the available oxygen in the air. If you get any symptoms get some fresh air and within seconds to minutes you will feel fine. Have you ever started nodding off in a lecture or boring meeting and couldn't stop yourself? It was probably caused by increased Carbon Dioxide in the room.

Carbon Monoxide is a lot more dangerous. When you breath carbon monoxide it bonds to your red blood cells in your lungs. These cells are rendered unable to carry oxygen around your body. The level of affected cells can build up and prevent oxygen reaching your brain. Going outside for some fresh air will have no immediate effect. It can take over half an hour for the level of affected blood cells to decrease. Symptoms are nauseaa, dizzyness, headache, weakness, fits. (Many of the same symptoms as Carbon dioxide.) You cannot smell or see carbon monoxide. It is a very good idea to get carbon monoxide alarm.

Other substances: Many of the colours in glass are created from metal oxides and salts. When heated small amounts of the metals are driven into the atmosphere by the heat. Many metals are toxic and some stay in the body for many years. We should lobby our glass suppliers to provide information on the metal content of our glass.

All these issues can be addressed with proper ventilation. You should have somewhere for fresh air to enter your workshop and somewhere for air to leave. Fan assisted extraction is ideal.

Lung Cancer / Respiratory Dieases

Any powder / fiberous material poses a risk to your lungs. Especially bead release and Kiln paper. Wet it, wear a mask or ventilate well to avoid breathing it.


Propane

A bottle of propane is inherently safe. If treated properly it will not spontaneously explode or cause a fire. If mistreated it poses three main risks:

1. If it leaks it will displace oxygen and will cause asphyixiation in the same way as Carbon Dioxide.

2. It is highly flammable (which is why we use it). If it leaks it will mix with air and create an explosive atmosphere. Such an explosion could be serious enough to blow an external wall down but will probably not kill you directly. The resultant fire, smoke, flying debris and lack of oxygen could kill you.

Leaking propane does sink, but only briefly. It is heavier than air but will rapidly diffuse into any available space as it warms to ambient temperature.

Virtually every mains powered electrical appliance in your house is a source of gas ignition.

Domestic gas regulators contain a mechanism to restrict gas flow in the event of a pipe break. The higher pressure welding regulators used for glass torches allows a much higher flowrate.

3. If exposed to enough heat a bottle of propane can cause a different type of explosion powerful enough to destroy your house, and the neighbours' houses and blow out all the windows in your street. This type of explosion is called a BLEVE (Burning Liquid Expanding Vapour Explosion). Heat on the bottle causes the liquid propane to boil and the pressure in the bottle increases dramatically. The heat also weakens the bottle. When the bottle bursts a cloud of propane is instantaneously ejected and mixed with the surrounding air. Almost instantaneously this ignites causing a concussive explosion. Calor gas bottles are designed so that the valve mechanism is weaker than the bottle, this should mean that the top of the bottle should blow off before the pressure reaches a point where the explosion will very serious. You still get a high pressure jet of propane shooting through your house. Watch the following videos, some of them are of domestic gas bottles blowing.

http://en.wikipedia.org/wiki/BLEVE
http://www.youtube.com/watch?v=S3PgwSGWvkw
http://www.youtube.com/watch?v=LvThP6zdfMw
http://video.google.com/videoplay?docid=1505191406742106917#
This last one explains how it happens:
http://www.youtube.com/watch?v=sl-JgyQA7u0

Every propane bottle is different, every one has had multiple previous keepers and could have suffered abuse. All are adequate and tested to hold the gas safely under normal circumstances. In a fire some may survive intact, some may not.

If there is a propane bottle stored inside your house the fire brigade will only enter your house to save life. After saving life, their first priority will be to cool the bottle, even if it means the rest of your house is left to burn down. Could the fire brigade get a water hose onto your gas bottle from outside the house if there is a fire?

Calor gas guidelines do not allow propane to be stored indoors. (Butane can be because it has a much lower pressure and poses a lower risk.)
http://www.calor.co.uk/customer-services/lpg-safety/lpg-cylinder-storage/cylinder-storage-information/
http://www.calor.co.uk/customer-services/lpg-safety/lpg-cylinder-storage/full-and-empty-cylinders/
http://www.calor.co.uk/documents/43/original/code-of-guidance-for-storage-of-cylinders.pdf

Just because your house hasn't burnt down and your gas bottle has caused a problem in the last 20 years doesn't mean it wont happen tonight.

If your propane bottle comes into contact with fire it is placing everyone in your house and your neighbours at risk of death. It is illegal to store propane inside a domestic property for good reason.

Would you expect a fireman to enter a burning house containing a gas bottle to save the life of your family?

My workshop consists of stainless steel tables, slate stone floor and brick walls. I have a fire extinguisher at the door. My gas bottle is located outside and the pipe runs through a hole drilled in the wall. Our house has specially designed escape windows in all bedrooms. Our upstairs windows are only ever locked when we are on holiday. Our door keys are always kept in the same place, near the exit (but out of reach of the letter box). We have smoke alarms in the hall, landing and workshop. We have a carbon monoxide alarm in the workshop. I use an extractor fan to pull fresh air out through a window.

Cigarette Lighters

If a hot piece of glass touches a plastic cigarette lighter it will melt straight through and allow the butane fuel to burst out. This will likely result in a fireball or jet of flame. The lighter could also be propelled across the room spewing our flames. Lighters can also spontaneously explode if they get too warm. I have personally experienced the results of a lighter exploding in my own car due to the sun warming the interior.

The safest ignition solutions are: Piezo gas lighter (the one which crackles and makes only sparks) or welding striker. Second best are matches or a metal cased gas lighter.

In 2005 there were 57,400 house fires in the UK, 487 people died.

Stuart

princess pink

Now this just makes me wanna give lampworking up at the risk of killing everyone! My propane tank is kept inside my garage which is separate building to the house. Have no way of drilling through the wall as it's my parents property. I could put it on the drive but it would be in the vicinity of a lot of cars (and evil cats). I always have the door of the garage mainly open. Been doing it this way for a year and it seems to be ok...

stuwaudby

Storing the bottle in the garage is a good solution so long as no one is sleeping in there.

Bringing the bottle into the house when using it and then returning it to the garage for storage is also fine.

Stu

princess pink

ok but is it ok to store the propane in the garage whilst i'm torching? as in the bottle is a metre or so away from the torch in a nice little corner next to my oxycon.

Redhotsal

Quote from: stuwaudby on April 20, 2010, 02:53:43 PM

Other substances: Many of the colours in glass are created from metal oxides and salts. When heated small amounts of the metals are driven into the atmosphere by the heat. Many metals are toxic and some stay in the body for many years. We should lobby our glass suppliers to provide information on the metal content of our glass.


What a utopian thought Stu......ain't never going to happen though.

Nice work - comprehensive. If you're scared by any of this you shouldn't be, but if it's made you think a little more about potentially how dangerous this hobby could be then it's done a good job.

helbels

#5
This thread has actually reassured me quite a bit about the way I work.  Yes, got ventilation.  Yes got heat resistant surfaces.  Yep have fire extinguisher to hand but need to move it's position having read this.  Need to ensure no paper goes in waste bin near workspace.  Have carbon monoxide detector. Put propane outside after use as can't drill through wall.  Torch is bolted to bench.  All in all I think I'm ok.  Good thread though - made me think.

One thing I should point out though Stuart is that calors advice on use of propane actually says it should only even be USED in commercial premises - they don't sanction it's use at home at all

stuwaudby

Princess - The gas bottle is quite safe. It takes a lot of heat (hundreds of degrees) before the strength of the steel is affected. You could probably try to heat it directly with your torch for hours before there would be a risk. The bottle only poses a risk if it is engulfed in a larger fire. Just remember to turn it off at the bottle when you have finished every night. If there is a fire in your garage then get everyone a long way away and tell the fire brigade exactly where the bottle is located.

Your biggest risk is dropping a very hot bead onto your gas pipe or something flammable. Do you have something handy to quench a fire quickly?

Redhostel - Thanks for the feedback. The intention is indeed to educate everyone on the risks so they can make their own decisions using accurate information.

stuwaudby

Redhot Sal,

UK COSHH regulations require a supplier to provide data sheets to highlight hazards and safe use upon first supply. If a supplier refuses to supply the information then the HSE require them to be reported.

COSHH regulations only apply to "packages" supplied to employers.

A supplier to domestic customers retains responsibility for any damage caused by the article supplied.

Personally I would not be happy if I found out that some colours of glass contained lead. the following is a list of metallic pigments from Wikipedia. Lead and Mercury would be particularly worrying. Makes you wonder what the metallic grey is that results from reducing some yellows and creams.....

* Cadmium  pigments: cadmium yellow, cadmium red, cadmium green, cadmium orange
* Carbon pigments: carbon black (including vine blac, lamp black), ivory black (bone char)
* Chromium pigments: chrome yellow, chrome green
* Cobalt pigments: cobalt violet, cobalt blue, cerulean blue, aureolin (cobalt yellow)
* Copper pigments: Han purple, Egyptian blue, Paris green, verdigris, viridian
* Iron oxide pigments: sanguine, caput mortuum, oxide red, red ochre, Venetian red, Prussian blue
* Clay earth pigments (iron oxides): yellow ochre, raw sienna, burnt sienna, raw umber, burnt umber.
* Lead pigments: lead white, cremnitz white, Naples yellow, red lead
* Mercury pigments: vermilion
* Titanium pigments: titanium yellow, titanium beige, titanium white, titanium black
* Ultramarine pigments: ultramarine, ultramarine green shade
* Zinc pigments: zinc white, zinc ferrite

Redhotsal

#8
Call me Sally.... ;)

I think yellow and cream is selenium?

I remember reading the safety sheet that came with some ancient Glass Alchemy samples of boro. The heavy metal content scared me so badly that I was actually a bit frightened to use them. Which, does sort of lead on this observation about safety sheets, viz:

Having been the purveyor and receiver of many safety sheets in a previous life - my conclusion is they're not that useful to the average lay person. I don't count myself as "average lay person" having a scientific background and being the acting health and safety officer for the company I used to work for. Even so , they're not that useful at first glance to me either.

What you want to know, as a bead maker is, is this glass going to harm me? Does it release vapours or particles which are going to harm me during the process of bead making and how cumulative is this level of harm?

You are so not going to get an answer to this from the standard manufacturers - Effetre, Bulleye, CIM. CIM - for example is made in China, and from my experience in working there in the 90s (that's in China, not at the CIM factory!) they don't put an emphasis on safety. It's just not going to happen. And it won't happen from the suppliers either. As far as glass beadmaking goes it's Frontierland.

I've found that the question of safety is as contentious as the dreaded topic of "copying" when it comes to discussion and debate. You have two sorts of people - the first sort know (or think they know) the risks associated with bead making. They accept these risks and work with them. They don't want anything to be regulated, changed or restricted. The other sort of people do want regulation of some sort, because it's such a potentially big area of concern. Let's not beat around the bush - the great majority of bead makers are female, some may be pregnant, and many have dependents who are just as concerned about their safety.

If you risk assess a rod of glass the top risk is cutting or injuring yourself with it, the next risk is getting a burn off a hot rod and way down in the risk is long term cumulative poisoning of cobalt/cadmium/silver.....Rightly or wrongly......

I dunno what to do about safety - I think you can only look at your own situation and say to yourself "am I doing my level best to ensure that I'm not going to burn down my work space/cause a gas leak/prevent myself from being burned and cut....?" And if you teach bead making you have a duty of care to encourage your students to ask these question. And then after that you have to accept that people will do what they do.

princess pink

Quote from: stuwaudby on April 20, 2010, 03:32:34 PM
Princess - The gas bottle is quite safe. It takes a lot of heat (hundreds of degrees) before the strength of the steel is affected. You could probably try to heat it directly with your torch for hours before there would be a risk. The bottle only poses a risk if it is engulfed in a larger fire. Just remember to turn it off at the bottle when you have finished every night. If there is a fire in your garage then get everyone a long way away and tell the fire brigade exactly where the bottle is located.

Your biggest risk is dropping a very hot bead onto your gas pipe or something flammable. Do you have something handy to quench a fire quickly?


yup i got me a couple of fire extinguishers, one within arms reach and a big glass of water if i need to quench somthing quick!

Helen G

I have first hand experience of something hot igniting a hose attached to a canister of gas and that was pretty hair raising as the hose was flayling around like a demented snake breathing fire  :o Fortunately a powder extinguisher was very close to hand and there was nothing particularly flamable in the immediate area.
I hasten to add it was years ago when I was working in silver and hopefully these days I am much more saftey aware!

Zeldazog

Quote from: Redhotsal on April 20, 2010, 04:30:57 PM

What you want to know, as a bead maker is, is this glass going to harm me? Does it release vapours or particles which are going to harm me during the process of bead making and how cumulative is this level of harm?

You are so not going to get an answer to this from the standard manufacturers - Effetre, Bulleye, CIM. CIM - for example is made in China, and from my experience in working there in the 90s (that's in China, not at the CIM factory!) they don't put an emphasis on safety. It's just not going to happen. And it won't happen from the suppliers either. As far as glass beadmaking goes it's Frontierland.

Bullseye give this information about Food Safety and levels of lead or cadmium, and which glasses they're in (remembering it's USA FDA guidelines they're using):  http://www.bullseyeglass.com/products/faq#faq_011

Not sure how much this relates to "danger" in bead-making - I was under the impression that the lead level is very safe as it is bound up with the structure of the glass, and is therefore stable.   I know there was a thread a few months back about the safety of lead crystal ware.


SilverGems89

i store my gas inside, i have no other choice, but i dont see it as a big problem, i disconnect my regulator from the bottle when im done and bleed all my pipes after every session, and when you think about the number of people who keep gas heaters and such inside their homes you realise its not drastically dangerous,as long as you use your common sense!

stuwaudby

Quote from: SilverGems89 on April 20, 2010, 10:13:13 PM
i store my gas inside, i have no other choice, but i dont see it as a big problem, i disconnect my regulator from the bottle when im done and bleed all my pipes after every session, and when you think about the number of people who keep gas heaters and such inside their homes you realise its not drastically dangerous,as long as you use your common sense!

A gas bottle is not dangerous until there is a fire. Anyone who has the choice should store gas bottles well away from where they sleep.

All domestic gas heaters use butane (blue calor bottles) which has a much higher boiling point and lower vapour pressure than propane. Butane is safer, but still presents a hazard.

You would be better closing the bottle valve firmly and leaving your regulator connected, there is more chance of causing damage to the regulator seats with repeated connection / disconnection leading to a leak. The gas left in the pipes would not significantly accelerate a house fire and poses very little risk.



flaming beads

Wow...what a collection of very relevant info..thanks guys :)