Hi ttxela

Never come across this chemical before!

However, my starting point is that the UK has been decades behind some geographies when it comes to occupataional health risks including, in particular, those which present respiratory risks.

When I joined the HSE there were virtually no exposure standards and we then borrowed many from the American Government Conference of Industrial Hygienists (ACGIH) for the first version of EH40.

My next point is to apply the "Precautionary Principle" - just because something is not listed in EH40 OR the level of risk is not sufficiently documented doesn't mean that you shouldn't take precautions to limit exposure, but so as to apply a proportionate response.

Possibly the documentation you have for your LEV sets out what levels of exposure should be expected now that it has been commissioned and may compare that with international standards.

So, I found an SDS for borate buffer (though the constituents might be different from your substance) which indicates ACGIH Theshold Limit Values of 2mg per m3 as an 8 hour Time Weighted Average and a Short Term Exposure Limit at three times greater 

+ a "(vacated)" by which I assume it means no longer in force OSHA PEL of 10mg per m3 - I assume "vacated" as ACGIH has set a much lower TWA and STEL

+ NIOSH recommending 1mg per m3 so an even stricter recommended limit.

I would like to hope that the LEV is designed to enable exposure to be well under ANY of these limits.

The proof is in the pudding. I suggest you get some sampling done to replicate reasonably worst case operating conditions and see how the numbers play out.

There are so many problems with getting RPE to work as the sellers say it will on the marketing bumph that your objective should be to remove the need for reliance on RPE even as a back up for the LEV (and other technical mitigations), except possibly in relation to emergency scenarios.

So let's suppose the numbers come out as exposure at 0.5 mg per m3 then I think you would have a strong argument not to supplement the technical mitigations with RPE.

Then may be repeat the monitoring at e.g. yearly periods - though possibly if you are getting the LEV performance tested then further environmental sampling might be OTT.

Have you verified the SDS content? The supply chain is incredibly poor at cascading substance information especially formulators who rely upon their substance supplier information.

"Boric Acid" EC 233-139-2 / CAS 10043-35-3 or EC 234-343-4 / CAS 11113-50-1 via ATP 17 (EU 2021/849) is subject to Harmonised Classification as H360fd - this does not necessarily transfer to "Borates".

On the ECHA web site these entries show a Specific Concentration Limit of equal or greater than 5.5% w/w in a mixture in order to apply the classification to the product containing the substance.

This is mirrored on the GB Mandatory Classification List entry.

Originally Posted by: Roundtuit

Have you verified the SDS content? The supply chain is incredibly poor at cascading substance information especially formulators who rely upon their substance supplier information.

"Boric Acid" EC 233-139-2 / CAS 10043-35-3 or EC 234-343-4 / CAS 11113-50-1 via ATP 17 (EU 2021/849) is subject to Harmonised Classification as H360fd - this does not necessarily transfer to "Borates".

On the ECHA web site these entries show a Specific Concentration Limit of equal or greater than 5.5% w/w in a mixture in order to apply the classification to the product containing the substance.

This is mirrored on the GB Mandatory Classification List entry.

Argggh, well, no.... Coming from Facilities I'm working on my basic responsibility to ensure the LEV does what it should and takes enough of the hazard away to make sure what is left is not harmful. 

If I understand this correctly we're saying the manufacturer may have made an error in assigning the H360 classification due to the concentration in the finished product due to concentration? 

I'm inclined to believe the SDS and arrange some monitoring, I don't have the resources to doubt every document and work constantly from first principles. Presumably if the SDS has applied the classification wrongly this will then just serve as a reassurance test.

The substance you are talking about is a borate buffer, which is a mixture involving boric acid.  Boric acid has been used for lots of purposes including  in the food sector and in antifungal foot powders.

I am concerned about the LEV you describe as adjustable heads. Does that mean that the operator can adjust the distance between the LEV head and the spray head?  If so how will you make sure that they don’t move it out of the way when it is convenient for them but reduces its effectiveness  to zero. The HSE does not like this sort of  approach. I suspect that they would prefer to ensure the whole process to be  in a booth with operators staying well out of it.  Relying on RPE means that you have to make an assessment about things like how far the spray may travel? Is 3 m from the spray equipment safe or not?  

Originally Posted by: ttxela

I don't have the resources to doubt every document and work constantly from first principles.

I personally doubt a "lack of resources" would offer suitable defence in a court of law.

Whilst there may be duties upon suppliers to update their SDS in the event of new hazard information (such as an ATP), restriction or authorisation it is frequently the case documents remain in circulation until challenged by those further along the supply chain.

Within my current employment I am frequently presented with documentation that was last up to date two decades ago when the CHiP update arrived at the same time as COSHH was published. Since that time we have had 17 years of REACH, 15 years of CLP, 18 published ATP (not including the changes to candidate SVHC, restriction & authorisation annexes) and the introduction of UK REACH.

Even the "better" suppliers can be out of step with the constant evolution in the legislation so it is prudent to at least check what you are being told.

After all an SDS is merely the basis of information and instructions an employer must transmit to their employee under a COSHH assessment.

Originally Posted by: Roundtuit

Originally Posted by: ttxela

I don't have the resources to doubt every document and work constantly from first principles.

I personally doubt a "lack of resources" would offer suitable defence in a court of law.

I'm sure that is true, however in deciding how deep to delve into the technicalities of any situation has to be balanced by most folk with the resources available to do so. This is not the only issue/task which is on my plate at the moment and I have to consider the consequences of neglecting others to tackle this or how long I would have to delay dealing with this in order to gather the resources to deal with it in fine detail.

If I understand correctly the suggestion is that the SDS may be overstating the risk so in assuming the SDS correct I hope I am 'playing safe'.

Unfortunately as is often the case in real world scenarios I have inherited this issue from folk who have moved on and left limited information behind so am still in the process of trying to determine why certain decisions were made. I believe positionable LEV was installed as at the time of construction, information on the equipment being installed that generates the spray was unavailable or incomplete. I don't think this was necessarily a bad decision as in fact the heads have to be moved to remove the covers to adjust the machine etc.

Anyhow I'm currently talking to several environmental monitoring companies to determine who can help us measure the potential exposure. I shall update when I have their responses!

AK - been there, done that, too exasperated to get a T-shirt

Originally Posted by: ttxela

If I understand correctly the suggestion is that the SDS may be overstating the risk so in assuming the SDS correct I hope I am 'playing safe'.

To the extent that AK has mentioned - potentially and unnecessarily spending capital because an (M)SDS has been incorrectly interpreted.