Thread: Melting Lead - fumes

I'm currently setting up my casting operations.

I've been aware of lead poisoning issues since making sinkers as a kid over an open fire. Having personal acquaintances who suffered chronic lead poisoning from melting and casting in enclosed spaces also engaged my interest. Some years ago I researched and wrote a 2 page analysis for my Club of lead poisoning issues relevant to Pistol shooting and reloading. Main risk being primer and tumbling media dust on hands and surfaces. Main outcome being need for hand and workspace care and hygiene.

In my reading and research, current and past, I have not found any informed discussion of what happens with extracted fumes. Lead fumes cool and lead settles out onto surfaces. The risk of lead poisoning in the immediate workspace from fumes occuring at specific temperatures is therefore discussed along with the need for extraction ventilation. Table top fans are seen as worse than useless because they just distribute lead contamination around the work area. Cleaning and disposing of extraction system filters is mentioned in passing.

In most hobbyist melting and casting situations, extracting fumes externally to the workspace, or, working in an open air situation, is advised.

My question is about what happens in the immediate area to which fumes are extracted? Does lead in one form or another settle around the extraction point (yes) and to what extent ? Does it "blow" or "wash" away with wind and rain over time or accumulate? Is there an issue analogous to the elevated roadside lead levels from leaded gasoline back when I was a kid?

Common sense says not to plant my tomatoes around the extraction exhaust area. But exactly how big an issue is this or not? If I'm making bullets for personal use I probably won't create enough fumes to be an issue in this respect (lead contamination around external extraction vent). If I was manufacturing to supply both a domestic and an export market no doubt several workspace regulations would apply.

My guess is few home hobby casters pay much attention other than to their immediate work area and personal exposure..if you do run, say, a range hood type extraction system do you also
- filter
- clean filters regularly
- have any concerns about where you vent fumes re resulting localized contamination?

I have a floored area under a roof whuch is open on 3 sides. I'm planning to mount a 2nd hand kitchen range hood over my melting and pouring area with ducting of the exhaust away from the work area. I anticipate the washable stainless filters will cool and accumulate most of any fume carried lead. I plan regular brush cleaning of the filters with soapy water which will unfortunately go down the drain.

My biggest concern is where to place the duct vent. The work area is directly underneath a deck BBQ area and is surrounded by bush-garden that folk are in daily. I'm considering venting into a drum buried into the ground with porous scoria fill above.

Comments?

put a filter over the inlet, maybe adapt an HRV one and change it when it becomes blocked/dirty, trow it away in your rubbish collection

as my old science teacher come rubbish dump manager once told me "The best solution to pollution is dilution"

I spent many hours as a kid making lead sinkers in an open fire....this may explain a few things in my life. I live in the Kaimai Ranges and have made many lead bullets using a wood burner fireplace, so all the fumes go up the chimney and have probably poisoned all the deer....do not shoot or eat deer from the Kaimai's as they will be contaminated.

Originally Posted by 300CALMAN

put a filter over the inlet, maybe adapt an HRV one and change it when it becomes blocked/dirty, trow it away in your rubbish collection

HRV is crap. HEPA filter is the only filter I'm aware will filter lead particulate.

A range hood!! now that’s using the old noggin. Why didn’t I think of that? Maybe not bury the drum so it’ll be easier to cycle out the contents regularly.

I think I got more contamination as a cable jointer working in manholes than ever as a projectile maker. My key to avoiding the fumes was good cross flow ventilation and fluxing often, the smoke from fluxing shows where the fumes are heading. Wear something that you only use for that task such as some old overalls, try and use gloves of some description preferably non melty ( you can get cheap cotton ones from the big shed style shops.) If in any doubt get a mask with the appropriate filters too.

Ive never been aware of lead producing fumes, would have to be quite hot to produce any significant vapor.
Mercury is much more of an issue when heated, lead doesnt seem to form vapor like mercury does.
Ive done a fair bit of soldering, and always washed my hands afterwards, you are more likely to be exposed to lead via ingestion with poor hygiene practices.
And as mentioned, lead dust is of concern if you are handling bullet traps or have been grinding lead.
If in doubt, get a blood test, it will show if you have high levels.

if you have eaten wild duck there is a good chance you have ingested lead shot.

Yep, when you heat lead it starts to smoke. Bad stuff.
You also need to flux the hot lead for casting.
A 1/2 walnut size piece of dripping or a wee lump of candle wax will work well.
This gives off more smoke, which you hold a flame to and that smoke will ignite (I used a rolled up newspaper taper. A wee gas torch would be great).
That flaming 'smoke' is burning off a lot of the bad stuff but yeah, a mask would be handy.
Stir the hot lead with (for example) an old hacksaw blade. The crap will stick to that.
Bang that on the ground a couple of times and the slag falls off.
Give the hot lead another swirl anyway. No more slag on the stirrer?
Good to go.
I used to do this in a single garage, with the main door open but with no mask.
Probably left lead contamination right through that garage. But I did make some lovely shiny smooth lead Minie balls for my .45 and .58 cal muzzle loaders.

Originally Posted by Grey Kiwi

Yep, when you heat lead it starts to smoke. Bad stuff.
You also need to flux the hot lead for casting.
A 1/2 walnut size piece of dripping or a wee lump of candle wax will work well.
This gives off more smoke, which you hold a flame to and that smoke will ignite (I used a rolled up newspaper taper. A wee gas torch would be great).
That flaming 'smoke' is burning off a lot of the bad stuff but yeah, a mask would be handy.
Stir the hot lead with (for example) an old hacksaw blade. The crap will stick to that.
Bang that on the ground a couple of times and the slag falls off.
Give the hot lead another swirl anyway. No more slag on the stirrer?
Good to go.
I used to do this in a single garage, with the main door open but with no mask.
Probably left lead contamination right through that garage. But I did make some lovely shiny smooth lead Minie balls for my .45 and .58 cal muzzle loaders.

Where you used dripping I used bees wax.

Originally Posted by DavidGunn

if you have eaten wild duck there is a good chance you have ingested lead shot.

David, I’ve chewed on hundreds of lead slugs, always running around with a mouth full of lead

Originally Posted by Old_School

Ive never been aware of lead producing fumes, would have to be quite hot to produce any significant vapor.
Mercury is much more of an issue when heated, lead doesnt seem to form vapor like mercury does.
Ive done a fair bit of soldering, and always washed my hands afterwards, you are more likely to be exposed to lead via ingestion with poor hygiene practices.
And as mentioned, lead dust is of concern if you are handling bullet traps or have been grinding lead.
If in doubt, get a blood test, it will show if you have high levels.

From Michigan State University- Safety Pamphlet for Bullet Casters:

"Know lead properties:
Lead melts at 621
°F. Fumes are released at 900
°F. Lead can
be breathed in and also settle on surfaces. Lead oxide (fumes
mixed with air) forms a fine yellowish/brown dust. Even with
good ventilation you have 100% chance of lead dust in your
"Lead Area". Good hygiene and ventilation are the best way to
reduce lead exposure. The main hazard activities involve hot
lead - smelting, casting and handling dross (the contaminate
residue that is skimmed off in the melting process)."

Don't put the range hood over the smelting pot, put it behind it so it's not pulling the fumes past your head but away from you. Wear a decent 3M 6200 type half face mask with good matching goggles or a P3 full face mask with the correct metal fume filters, and be bloody fastidious about water or moisture where you are working...

If you can find some fibrecement board, this makes a nice fume area and is perfectly good as a solid fume settling point that's quite permanent and if you have some hinges loafing you can set it up so that it just folds out and bridges the gap to the fume hood. The HRV or similar HEPA-rated filters you get from Bunnings or the like for the home ventilation units are good, but I'd use the metal filters in the range hood (pretty much non flammable if cleaned of fats) and then a section of ducting after the rangehood into a filter holder and by that stage (3-odd meters after the range hood) the fume should have either dropped into the ducting and settled or will get caught in the filter on the way out for later disposal. Discharge the outlet from the range hood over a pathway/driveway/back lawn area that is fairly 'dead' ground...

Do we need to talk about water introduction to the crucible?