Safety while machining FR4/G10?

balou

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I think it'll be best if I split this away from my other thread: http://www.candlepowerforums.com/vb/showthread.php?t=253237

That is smelly, nasty, abrasive material to work with ... you should consider a dual element full face respirator combined with suction through a HEPA or Gore-Tex vacuum filter. Once those micro fibers of glass get lodged way down in the lungs (alveoli) they become permanent residents :shakehead

From the other thread:
At the moment I'm using a household vacuum cleaner duct-taped to the top of my working plate and a simple cotton facemask. So I'm not entirely unprotected, and I've never seen visible dust flying around, but I think a separate thread on that would be in order...
So here it is...
I'm currently working on my cardlight prototype in my room, and I didn't care to much about real protection, except that I found out that it smelled particularly nasty and produced very fine dust from former experiments years ago...

For my prototype work: what kind of facemask would you recommend?
What kind of suction? Anything with which I can use a normal household vacuum cleaner?
Comments on the fact that I am doing this whole thing in my bedroom?

I must say, I'm a bit scared right now, especially because I worked with FR4 before, without any protection. It was rather small stuff, mostly messing around with broken or half broken electrical equipment, but still. Btw, what are the dangers of phenolic paper? The cheapskate I am, I almost always bought phenolic paper when needing cheap PCB veroboard :poke:. Should at least not contain fibreglass...
 
G10 is a member of a class of materials called phenolic laminates, because they contain phenol. Phenol is not classified as carcinogenic but can cause respiratory irritation, headaches, and burning eyes. People who had skin exposure to high amounts of phenol had skin burns, liver damage, dark urine, irregular heart beat, and some died. Ingestion of high concentrations of phenol has resulted in internal burns and death. In animals, breathing air with high levels of phenol resulted in irritation of the lungs. Repeated exposures induced muscle tremors and loss of coordination. Exposure to high concentrations of phenol in the air for several weeks caused paralysis and severe injury to the heart, liver, kidneys, and lungs, and in some cases, death. Some animals that drank water with very high concentrations of phenol suffered muscle tremors and loss of coordination. http://www.atsdr.cdc.gov/tfacts115.html#bookmark04


Mix phenol with epoxy resins, add glass fibers & you have G10, G11, G5, etc.


what kind of facemask
Lots to choose from. A half mask respirator covers the nose & mouth dosen't cost a lot, probably $25 for the mask & another $25 for a pair of HEPA filters.



What kind of suction?
A Shop Vac with Gore-Tex filter will catch most of the ultra fine dust, and a powered HEPA filter can then trap the finest particles.


I worked with FR4 before, without any protection.
The effect is cumulative. You can't do anything about the past, but you can protect your lungs from now on.
 
What strikes me as odd - every PCB etching/drilling information I could find only talked about wearing eye protection when drilling - not a single one mentioning any kind of respiratory protection :shakehead.

I searched for material safety datasheets concerning G10, and found this (I actually had the page of Atlas Fibre already open, they're the first manufacturer that came up using a quick google search):
http://www.atlasfibre.com/specifications/material-safety-data-sheet.html
Respiratory Protection
If machining operations are not adequately ventilated, a N.I.O.S.H. approved respirator should be worn.
Ventilation
Mechanical(general) preferable, local exhaust acceptable.

So again I'm puzzled - this seems to indicate that standard common sense precaution against dust should be taken, but not much more?
 
standard common sense precaution against dust should be taken, but not much more?
That depends on what value you place on health & longevity. The effects of inhaling any of the more nasty particulates (glass fibers, asbestos, coal dust, tropical wood dust, metal dusts, welding fumes, etc.) are not immediate - they are cumulative & sometimes take years to develop to the symptomatic stage. The science is not exact, as some people are more sensitive to certain dusts than other people. The lungs (and eyes) belong to you ... and you may be able to find replacements if you screw up the first set :shakehead

...local exhaust acceptable...
In some less developed parts of the world, toxic liquids can still be dumped into waterways, and harmful dusts can be sucked out of one person's work space & blown somewhere else - not a problem, unless you happen to live "somewhere else".
 
Lets just say that exposure to that dust has left me with a powerful allergy to printed circuit boards resulting in contact dermatitis that is very painful. The respiratory affects have not appeared yet but I am sure they will rear their ugly head down the road. Use ALL the protection you can get for the skin and the lungs. Do NOT do this in your bedroom either!!!!
 
This whole thing sucks pretty hard. I once thought I could fabricate a small run all by myself, and now I even have problems building a single prototype (finding a suitable workroom, proper ventilation, proper safety equipment)

I'm not saying I don't care about safety - I do, that's why I grounded my project for the time being. It's just that I never thought in the beginning that safety would be such a major concern.
 
Before you give up....

For one off fabrications, look for a tool known as a "nibbler". It's designed to make small cuts in sheet metal, but I've used it for printed circuit boards in the past. It has a little cutting head that bites out a small rectangular bit (maybe 1/16 x 1/18 inch) with each squeeze of a handle.

http://www.google.com/products/cata...r&oe=utf-8&cid=5212472774431229843&sa=title#p

By walking it around the outside of your circle you can cut a fairly neat 20 mm disc in 4 or 5 minutes. All you end up with is little chips which are not dangerous. You can then finish it off with a file, sander, etc and vacuum to clean up the edges.

There is a video of a manual nibbler at http://www.youtube.com/watch?v=1q3w2GsovJ4

Daniel
 
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I have played with various laminates and epoxies and the dust and fibers are a PITA to be sure. I currently use a strong vacuum nozzle mounted to the edge of my work bench and a diamond wheel on a flex shaft for cutting PCB's away from their sheet.

In the past when I was doing some of my own laminations and especially when working with carbon fiber, I would cut and grind and sand with flowing water; often over a sink. If you can work with flowing water you avoid airborne dust and the cooling keeps the epoxy or other resin hard and much easier to cut. Your abrasives will last much longer and not gum up either.

I would love to have a dental hand piece designed for wet work and I could do the stuff I am doing now over a sink with water cooling.
 
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