Hexavalent Chromium (Cr+6)?

[GoK4rtFanatic]

Hi, basically brand new to welding as a whole. I was wondering if anyone could explain some things to me. I have recently heard of this being a danger to welders. I’m not trying to sound picky or fussy or anything, but I typically like to know what I’m getting into before I do anything. I work with plain steel and I have been using FCAW for about 8 months or so, I just got a tig rig to start a new process and was wondering about chromium 6 exposure. I don’t plan to do stainless, but I would like to know, if there is any hexavalent chromium released when welding plain steel such as this. https://www.homedepot.com/p/Everbilt...1257/204225779

I hope I don’t come off as too worrisome, but I like to know when something will have an adverse affect on my health. Thanks.

[shovelon]

No, there is no chromium as an alloy in mild steel. But Hex6 is a nasty contaminant. I personally refuse to GMAW or FCAW stainless of any kind.

[Munkul]

I personally refuse to GMAW or FCAW stainless of any kind.

What he said GTAW welding of stainless is pretty safe in comparison, as the filler metal itself doesn't form part of the arc.

If you have to stick weld stainless, use a respirator and/or do it outdoors.

To be honest, we have stick welded stainless off and on over the years and seen plenty people retire afterwards... but may as well be safe when you know the risk.

[GoK4rtFanatic]

So what is the best way to clear this stuff? Respirator? Welding outdoors? Fan? Fume exhaust? Which of those is the ideal choice? I can’t really afford the fume extractor, but I can weld outdoors with a respirator. I will be doing gtaw for the most part outside (yes I know wind can affect gas flow, but it’s not windy where I work). I have heard negative pressure is better than a fan, but fume extractors seem wayyyy overpriced. I’m all for being safe and smart but wth is with fume extractors being thousands of dollars?

[albrightree]

Any device that claims to remove contaminants, particulate, welding or soldering fumes, paint spray/solvents must meet a minimum standard of operation. In other words it must work as claimed, and will be tested. Especially if the air is to be returned to an occupied space. Simple pleated paper filters can't do this, more expensive filters are required. Employers are generally responsible to make sure the workplace is safe. You are a hobbyist , so it is up to you to be informed of the hazards of the work you're doing. Listen to everybody here, and then look up some real information on occupational heath and safety from manufacturers of those items, like 3M, Honeywell, and others. It is up to you to read all the information on the materials you have purchased to weld together. You know , all those little papers with the really small print that comes with every box of welding rod or wire.
One simple way to make a safer work space is to work on a table in front of a window with a fan exhausting outside. You can use cardboard, or plywood to help direct the fumes outside. You will need to leave a door or window partially open on the other side of the room to allow for fresh air make up. Another method is to put a shopvac outside and run a hose to where your working inside, this works well for soldering or TIG welding.

Good luck, and stay Safe !!

[GoK4rtFanatic]

Any device that claims to remove contaminants, particulate, welding or soldering fumes, paint spray/solvents must meet a minimum standard of operation. In other words it must work as claimed, and will be tested. Especially if the air is to be returned to an occupied space. Simple pleated paper filters can't do this, more expensive filters are required. Employers are generally responsible to make sure the workplace is safe. You are a hobbyist , so it is up to you to be informed of the hazards of the work you're doing. Listen to everybody here, and then look up some real information on occupational heath and safety from manufacturers of those items, like 3M, Honeywell, and others. It is up to you to read all the information on the materials you have purchased to weld together. You know , all those little papers with the really small print that comes with every box of welding rod or wire.
One simple way to make a safer work space is to work on a table in front of a window with a fan exhausting outside. You can use cardboard, or plywood to help direct the fumes outside. You will need to leave a door or window partially open on the other side of the room to allow for fresh air make up. Another method is to put a shopvac outside and run a hose to where your working inside, this works well for soldering or TIG welding.

Good luck, and stay Safe !!

Of course this is only necessary for stainless steel/ chromium steels, not mild alloy steel like mine? The rest I’ll be fine with a respirator and some airflow to push away the plume of smoke for FCAW and the light smoke of TIG? (Yes I would set up the fan so it would not blow the shielding gas away).

[And256]

So what is the best way to clear this stuff? Respirator? Welding outdoors? Fan? Fume exhaust? Which of those is the ideal choice? I can’t really afford the fume extractor, but I can weld outdoors with a respirator. I will be doing gtaw for the most part outside (yes I know wind can affect gas flow, but it’s not windy where I work). I have heard negative pressure is better than a fan, but fume extractors seem wayyyy overpriced. I’m all for being safe and smart but wth is with fume extractors being thousands of dollars?

95% of welding fumes come from a consumable electrode.
If you use a stainless-steel rod or wire on carbon steel, most of the fumes will contain Cr6.
Since TIG doesn't use a consumable electrode, it produces low fumes.
It is the only process I would use for stainless materials, and never stick of FCAW.

A local fume extractor (LEV) is less expensive than serious hospital bills, if someone gets sick from Cr6.
The most effective ways are: LEV, general ventilation (or outside), keeping your head out of fumes, and the respirator is the last one.
You can combine the last three.

The only way to expose yourself to Cr6 from carbon-steel base metal is if it's galvanized.
Some zinc coverings are chemically treated with chromic acid for added corrosion resistance.

[GoK4rtFanatic]

So would er70s-2 and er70s-6 have either stainless steel or chromium content? I’ll stick to welding low carbon steel with a respirator and in well ventilated areas, but would just like to know if those filler metals for tig would contain either stainless steel or chromium (If anyone happens to know).

[ttoks]

Almost ten years ago I worked for a company building LNG plants and they're OHS department decided to do some research into hex chrome.

We were welding 304 stainless pipe with 316L TIG, 316L stick and 316L dual shield flux core, we had 3M speedglas PAPR welding helmets with all the filters etc, so they got us to wear a collections device thing that collected samples of airborne contamination in our breathing zone right in front of the welding helmet, and rigged up inside the welding helmet while welding with TIG, stick and dual shield, and the results were really interesting.

flux core was by far the worst with massive amounts of Hex chrome, I can't remember what the scale used means but a 10 per hour of welding was deemed acceptable, the dual shield recorded in the thousands range, up to 3500 in one sample, stick was also very high, in the high hundreds to low thousands, averaging around 900.

The surprising one was TIG, at low amperage and low heat input values the hex chrome was almost non existent, but above 140 amps the level's spiked pretty high to almost 100, so ten times whatever the acceptable limit was set at, so even with TIG it's a good idea to take some precautions.

As for the PAPR's ability to filter out particles, they were very effective as long as they were fitted properly, the 3M mask's have an elastic chin cover thing that has to be tight around the chin, with no holes and leaks in the filter/air pump and hose, filters never lost they're effectiveness in filtering out the contamination, but they did clog and result in reduced airflow after about 15-20 hours of use (that is blowing the filters out every hour or so with compressed air and re-installing), the filters were a stack of the 3M gas organic filter, with the fine and course particle filters over the top of the gas filter.

As for the effects, in the training thi company put us through it's similar to concreters lung, the hex chrome particles are sharp and lodge into the tiny air sacks in your lungs both collapsing them, and causing scar tissue to grow around it which can be a trigger for tumor growth, overall it's pretty nasty stuff.

[albrightree]

SDS for Lincoln ER70s6 :https://www.lincolnelectric.com/asse...0000000377.pdf


SDS for Lincoln ER308 : https://www.lincolnelectric.com/asse...0000000363.pdf

Specifically check out Section 2 "Hazards Identification" substances formed under the condition of use.
Section 3"Composition/Information on ingredients" Reportable hazardous ingredients Mixtures in SDS's

Look for chromium, and or chromium(IV)

Every time you open a container of welding filler metal you should have an MSDS or SDS with it. Online is easier to see, the one in the box is incredibly small, super thin paper, and in 3 or 4 languages.

[Munkul]

SDS for Lincoln ER70s6 :https://www.lincolnelectric.com/asse...0000000377.pdf


SDS for Lincoln ER308 : https://www.lincolnelectric.com/asse...0000000363.pdf

Specifically check out Section 2 "Hazards Identification" substances formed under the condition of use.
Section 3"Composition/Information on ingredients" Reportable hazardous ingredients Mixtures in SDS's

Look for chromium, and or chromium(IV)

Every time you open a container of welding filler metal you should have an MSDS or SDS with it. Online is easier to see, the one in the box is incredibly small, super thin paper, and in 3 or 4 languages.

That doesn't tell you anything useful. It says Cr6 may be formed under conditions of use (GTAW/TIG), but it doesn't say how much.
Multiple independent studies have shown the levels of Cr6 released under stainless steel TIG welding is negligible. The same wire in MIG welding releases LOADS.

[GoK4rtFanatic]

So I couldn’t find an SDS in the tube for whatever reason, I did move around the rods from a few containers so may have lost then. I tried looking online and this is the closest thing I’ve found. The box says they are made in South Korea so that may be why I can’t find any info on them. I’m brand new to this, thoughts on the filler I bought (picture below).

[Munkul]

no pic showing

[GoK4rtFanatic]

Sorry, here is the photo.

[albrightree]

That doesn't tell you anything useful. It says Cr6 may be formed under conditions of use (GTAW/TIG), but it doesn't say how much.
Multiple independent studies have shown the levels of Cr6 released under stainless steel TIG welding is negligible. The same wire in MIG welding releases LOADS.

I don’t plan to do stainless, but I would like to know, if there is any hexavalent chromium released when welding plain steel such as this.

The SDS shows that there is no chromium or chromium IV in the 70S6 wire. They also tell you what the exposure limits are, and yes your right they don't express how much is released in the welding process

Just curious, but how much is " LOADS " ? I ask, because to find a suitable respirator you need to know the concentrations in mg/m3 and looked quickly and didn't find any. I wonder what respirator is even close to sufficient. Some of the 3M P100 filters are rated for welding fumes, but don't specifically mention stainless or Chromium IV.

cheers

[Munkul]

This is the report i read a few years back, since then I haven't done any further research, I just have read that various countries' enforcement authorities (similar to our HSE) have found similar results and implemented similar approaches to welding stainless.
You'll notice that there is no specific requirement for LEV when TIG welding stainless.

https://www.hse.gov.uk/research/rrpdf/rr770.pdf