[NOSTOPIN]

Hello, I’m Eric

I typically only read these forums, and rarely can’t find an answer deep in a thread, but this time I’m stumped so here I am to ask my question.

I’ll include the question here as well as in the general welding.

I know a lot of people weld SST with just a N100 half mask, and some even use PAPR’s... I personally use a Versaflow PAPR all day at work due to the process environment I’m in manufacturing AM powder. The Versaflow only has HEPA filters available. So when it came to buying a new Speedglas hood to use with my Versaflow, I ended up going with the ADFLO PAPR as you can add a OV/gas filter cart after the particulate filter.

I’m a contractor, so I buy what I want... however my clients guys that I’m welding with are at the mercy of their employer to get them their PPE. And a PAPR w/HEPA filter far exceeds what OSHA calls for (from my understanding). So these guys can’t get the new ADFLO PAPR’s for a couple hundred more.

My observation that leads to my question:
HEPA filtration starts at around .3 micron
Hex chrome fume is distributed in particle sizes from .05 - 2.0 micron
I read somewhere that 80% of the particle distribution is in the smaller size range... closer to the .05 micron size
If this is true, most of the hex chrome fume could pass through a HEPA filter.
My evidence of this... put on a PAPR with only a HEPA particulate filter and fart. You didn’t smell 100% of that fart, nothing above .3 micron at least, but you smelled way too much of it.

My question:
What do you guys that weld SST all day use?

[weldin mike 27]

That seems silly by 3m to not supply the full range of filters. However, I see that the adflo unit is interchangeable with the versa flow hood, so you can get an adflo and swap it for your current one, therefore allowing you to use the full range of filters.

https://www.ebay.com.au/itm/3M-Versaflo ... 4354639144?

[Oscar]

SST?

[weldin mike 27]

SST?

Stainless steel, evidently

[manac]

Had to look it up.
Surface Tension Transfer (STT) Pipe Welding.
A Lincoln mig process.

[JayWal]

Had to look it up.
Surface Tension Transfer (STT) Pipe Welding.
A Lincoln mig process.

That was my thought too, but that's a pretty niche group. Lot of people have never heard of STT

Sent from my SM-G970W using Tapatalk

[weldin mike 27]

He's referring to hexavalent chromium. That what's led me to believe he means stainless steel
But, until he comes back, we'll never know.

[BillE.Dee]

I read that he is asking about S S T,,,,not S T T. Like Mick stated, we have to wait for his return.

[dcsco]

Stainless steel tube, maybe.