In my experience, people generally sample the total quantity and then make assumptions about the fractions of each constituent.

For instance, when welding stainless steel, from a total fume measurement you can make a reasonable estimate of the likely quantity of something like Cr(VI) using the consumable manufacturer's data.

What welding process are you monitoring?

I'm not certain as to the best sampling strategy to apply Jane. Representative should see samples for chromium, iron oxide, oxides of nitrogen & manganese. We weld stainless, mild and aluminium at any point during the day.

Have you carried out air monitoring before?

http://www.twi-global.co...plying-with-the-coshh-r/

"Employees must have access to their own monitoring results and to the collective results of any health surveillance"

Hi Jane, I've no idea who TWI are. The processes vary from day to day, but centre strongly around TIG/MIG welding of stainless, mild and aluminum.

Consumables include the wires for those 3 materials, and tungsten for TIG. I have had a response from an occupational hygienist and waiting for a further 2 responses.

All comments are welcome

Thanks Jane,

You've reeled off much of what I discussed with the OH since that last post, but great to see others know their stuff too.

I've emailed the list of gases we use as well as consumables at his request, we can discuss a strategy once he has prepared a brief.

Thanks for the info

Hmm..while Tungsten is not consumed (much, depending on manual dexterity!), it does have a profile ground onto the tip. This can cause problems IF you are using a thoriated electrode.

http://www.twi-global.co...ted-tungsten-electrodes/

Quite true. Largely because nobody bothers anyway.

Rather than wasting time & money on OH, why not just assume the fume is worse case for the process and put good (higher hierachy) controls in place.
Decent LEV properly and consistently used should pretty much eliminate breathing any fume and make the welder's life more pleasant.

COSHH requires you to achieve the lowest levels of exposure, and not "just ducking under the MEL"

It never ceases to amaze me some of the Ego's in this forum. Perhaps you've got got an MD with an open cheque book Walker, or at least not encountering the same arguments as me. And since starting this assessment process JohnMurray I've gone through the HSE's guidance table on 4 different metal categories, though Chromium was the first substance I referenced on the basic CoSHH assessment thanks to a BOHS document from their breath freely campaign.

It's all in motion now, thanks for the contributions

Walker,

despite that early morning reply maybe benefiting from a coffee and breakfast before answering, I am always grateful for any assistance including yours.

My own approach to management is educate but discipline and the one thing I come up against more than anything when asking workers what their barriers are to success in H&S behavior usually falls between a couple things. Either, we don't know how to make procedures work, or the H&S can tell us what to do but not how to do it - both clearly are communication and skills bordering confidence issues on both parties involved.

on linked-in there are now regular meme's (and other social media) showing photos of safety professional with the line 'I don't know anything about your job, but I'm here to tell you how to do it' (or similar with expletives).

Our profession is difficult, we have to build trust and relationships and improve the culture through image and competence in all aspects including 'soft skills'. The quickest way to kill that, is to be condescending and seen to be 'key holders of knowledge' rather than encouraging everyone to know what we do, or at least as much to keep them safe. Both of which are comments I receive regularly where safety has failed within an organisation.

To sumarise, John doesn't need defending I am grateful for assistance, as I am yours. But in the dry & arid world of H&S content and emails/ black and white text, I'd ask you to equally consider how your communication may be received regarding structuring of sentences and tone.

Other than that, thanks again all - I am thankful after moving industry to have such helpful people within our forum.

Adale, the method for welding fume sampling is very similar to 14/3, the only difference may be the choice of filter paper (depending on which method you choose for metal analysis) and sampling head - there has been some interesting developments on the best choice to use here especially if you are sampling in the breathing zone 'under' the visor

Further guideance on sampling methods and materials (in addition to MDHS) can be found from reputable supliers such as:
https://www.skcinc.com
or
http://www.salltd.co.uk/

I know from personal experience the latter will always be happy to discuss with you the best approach to take ^ (no connection)

But you raise an interesting question in your original question, "a strategy for exposure monitoring", this will depend on what it is you are trying to show.

Compliance with exposure limits for example applies to every worker, but it is usually not possible or practical to measure each, enough times (this is also of significance - did you know it has been recommended to have over 30 samples! per SEG to have statistical confidently in the results) to determine compliance. But where different workers are carrying out the same task in the same way, it is usual to limit the number of workers sampled by grouping them into Similarly Exposed Groups (SEGs), and to make measurements on only some of the members of each group.

Assigning workers to a SEG usually requires discussion and observation of the work activities to ensure the materials handled, the processes involved, and the ways of working are the same. People can do the same task, but very differently (position of the head in the fume plume, or use or position of LEV for example). You may even want to do a initial observation or pilot study if there are several methods of working to determine which is most likely to be the best (lowest exposures) and then train / advise other workers accordingly, sometimes video can be a real help here!

Perhaps I am not adding anything specifically to the original post, but I thought it was a good oportunity to raise an all to common issue with exposure monitoring, I often see results of monitoring but if the choice of person monitored, number or type of sample has not been thought through (the "strategy") then the results are often meaningless wihtout this context.

If anyone is interested in this subject further information can be found in:
AIHA Publication: A Strategy for Assessing and Managing Occupational Exposures, 4th edition
BOHS Publication: Testing Compliance with Occupational Exposure Limits for Airborne Substances (free)

Or the massive amount of free! approved hygiene training information, notes and manuals available at:
http://www.ohlearning.com