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mrkjd  
#1 Posted : 03 August 2023 08:25:47(UTC)
Rank: Forum user
mrkjd

Any DSEAR experts out there?

I have recently inspected a Storage / Workshop that contains marine systems and I have little experience of implementing DSEAR. Some systems are powered by Lithium batteries. I have been boning up on DSEAR requirements but can find nothing on storage of lithium batteries. I know they are a UN Hazard Class 9 so am I right in thinking they do not come under DSEAR provisions?

What about battery charging areas? They have a dedicated charging area with LEV etc but it does not appear to be classified as a DSEAR Hazard Zone by building management and there is no DSEAR RA though there is a SWOP and operational activity RA for battery recharging.

I am also confused whether DIESEL comes under DSEAR. They have a bunded fuel cube of <1000L. Again, there are basic arrangements in place but no specific DSEAR RA. I have read in the past that diesel does not come under DSEAR  and general RA arrangements are considered adequate where storage is <1000L. 

Finally, there are compressed gases (O2 / CO2 / Acetalyne). Again general storage arrangements, RAs and SWOP are in place but no specific DSEAR assessment. 

I believe they should have a DSEAR RA undertaken. My understanding is that the Building owner should do this under the arrangements in place (in terms of identifying Haz Zones / Building plans etc) but the user also has an obligation to DSEAR RA it's activities and processes (eg the Fuel Cube which is temporary and deployed). I thought I'd ask these questions on here before formally reccommending as there will likely be some push-back and I want to ensure my ducks are in line beforehand. 

John Elder  
#2 Posted : 03 August 2023 12:35:47(UTC)
Rank: Forum user
John Elder

Hi mrkjd

The risk assessment should have been conducted even if the resultant findings are Non Hazardous as lease you can show what you based the assessment upon.

I will go through your questions one at a time where you are confused.

  1. Lithium Batteries, your biggest threat is thermal runaway due to a damaged cell starting a fire. Or a localised fire in the area started by something else. For guidance on all thing’s lithium read:

DNV.GL Maritime Battery Safety Joint Development Project Technical Reference for Li-ion battery explosion risk and fire suppression. If you can find a copy on line.

  1. Diesel, as per EI 15 and 200 litres is the threshold value for a flammable liquid at a temperature above its flash point to consider DSEAR Assessment. Diesel has a flash point of around 60⁰C so is not likely to be at above its flash point. However it is a Fluid Category C which can on release be at a temperature above its flash point, or form a flammable mist or spray. The main risk of fuel cubes is the refuelling operation and tanker deliver if delivered under pressure as opposed to gravity fed. Also the tanker vehicle may have had unleaded fuel in the tank prior to being filled with diesel and the ullage space of this vehicle may have petrol fumes within being vented as fuel is delivered. Consider the above then make your decision. Also consider diesel tank ullage spaces with fumes and vapours being vented to atmosphere during the refuelling operation. Your main issue will most likely be increased fire rise as opposed to DSEAR Explosion Risk in most instances.

  1. Compressed gases whether flammable, toxic or inert the risk in main is a localised fire heating the cylinders causing them to explode as opposed to an explosion risk from a leaking cylinder, this is managed using BCGA GN 41 separation distances (Its free to download). And BCGA GN 13 DSEAR Risk Assessment Guidance.

A leaking Acetylene cylinder based upon historical data in these standards for a 0.1mm leak located outside, a gas release is considered to be horizontal (for example, cylinder valve seat not closed leak tight) or vertical (for example, leaks from the valve gland or the valve to cylinder neck joint) when conducting gas dispersion modelling. Gas dispersion modelling using the release rates estimate the extent of the hazardous area as follows. has a hazardous zone as follows Acetylene 15bar dissolved Acetylene cylinder gives 2.27e⁻⁵Kg/s This gives a Horizontal release 65mm Horizontally with a width of 4mm. And a Vertical release, 62mm vertical with a width of 4mm.

thanks 1 user thanked John Elder for this useful post.
peter gotch on 03/08/2023(UTC)
mrkjd  
#3 Posted : 03 August 2023 13:57:03(UTC)
Rank: Forum user
mrkjd

Originally Posted by: John Elder Go to Quoted Post

Hi mrkjd

The risk assessment should have been conducted even if the resultant findings are Non Hazardous as lease you can show what you based the assessment upon.

I will go through your questions one at a time where you are confused.

  1. Lithium Batteries, your biggest threat is thermal runaway due to a damaged cell starting a fire. Or a localised fire in the area started by something else. For guidance on all thing’s lithium read:

DNV.GL Maritime Battery Safety Joint Development Project Technical Reference for Li-ion battery explosion risk and fire suppression. If you can find a copy on line.

  1. Diesel, as per EI 15 and 200 litres is the threshold value for a flammable liquid at a temperature above its flash point to consider DSEAR Assessment. Diesel has a flash point of around 60⁰C so is not likely to be at above its flash point. However it is a Fluid Category C which can on release be at a temperature above its flash point, or form a flammable mist or spray. The main risk of fuel cubes is the refuelling operation and tanker deliver if delivered under pressure as opposed to gravity fed. Also the tanker vehicle may have had unleaded fuel in the tank prior to being filled with diesel and the ullage space of this vehicle may have petrol fumes within being vented as fuel is delivered. Consider the above then make your decision. Also consider diesel tank ullage spaces with fumes and vapours being vented to atmosphere during the refuelling operation. Your main issue will most likely be increased fire rise as opposed to DSEAR Explosion Risk in most instances.

  1. Compressed gases whether flammable, toxic or inert the risk in main is a localised fire heating the cylinders causing them to explode as opposed to an explosion risk from a leaking cylinder, this is managed using BCGA GN 41 separation distances (Its free to download). And BCGA GN 13 DSEAR Risk Assessment Guidance.

A leaking Acetylene cylinder based upon historical data in these standards for a 0.1mm leak located outside, a gas release is considered to be horizontal (for example, cylinder valve seat not closed leak tight) or vertical (for example, leaks from the valve gland or the valve to cylinder neck joint) when conducting gas dispersion modelling. Gas dispersion modelling using the release rates estimate the extent of the hazardous area as follows. has a hazardous zone as follows Acetylene 15bar dissolved Acetylene cylinder gives 2.27e⁻⁵Kg/s This gives a Horizontal release 65mm Horizontally with a width of 4mm. And a Vertical release, 62mm vertical with a width of 4mm.


Many thanks for the detailed reply John. Very helpful. what about battery recharging areas? 

I intend to advise that they contact the Building owner to conduct a DSEAR RA and we conduct a DSEAR of our user storage and processes which will identify the hazardous materials and capture where our usage scenarios (such as refilling etc) may have impacts and what mitigations are in place. We may have in-house fire officer or similar who can come across to do this or bring someone in. Is there a set periodicity for DSEAR RAs?

John Elder  
#4 Posted : 03 August 2023 15:59:43(UTC)
Rank: Forum user
John Elder

mrkjd

Battery charging areas other than Lithium type batteries comes under the following standard for working out the gases given off and ventilation rates.

BSEN 62485-2 Safety requirements for secondary batteries and battery installations.

Everything you need to calculate the gases given off and ventilation rates for control in preventing an explosive atmosphere developing is in that standard.

Regarding Risk Assessment frequency. Every 3 years maximum unless there is a change to  how the process is conducted, substance being used, quantities being used, room/plant layout affecting ventilation or other changes which might cause concern and warrant an update of the risk assessment.

This is all I do for a living and its not worth dabbling in this subject matter yourself as its quite a complex field with multiple standards to refer to.

Carefully vet your proposed DSEAR Assessors (And this is difficult) as 95% of those advertising and conducting these works should be considered as DSEAR Dabblers as opposed to competent DSEAR Assessors. This leads to over or under classification and expensive ATEX works being recommended which otherwise would not have been required.

Unfortunately the websites and lists off services offered is no firm guide as to the competence of the assessors behind the website, and with no governance within the field you are in the lap of the gods as to whom you choose and what you end up with.

Ian Bell2  
#5 Posted : 04 August 2023 12:24:34(UTC)
Rank: Super forum user
Ian Bell2

I would like to think I'm a bit more than a 'DSEAR Dabbler', as I spend most of my life doing DSEAR assessments/process safety.

As other have said the risk with lithium batteries is thermal runnaway.

From the DSEAR point of view batteries are of interest because they release hydrogen as part of the re-charge cycle - as a result of the electrolysis of the electroylyte. The rate of hydrogen release is given by Faradays Law. The standard mentioned BSEN 62485-2 Safety requirements for secondary batteries and battery installations does not consider lithium batteries because they don't release any gases under normal operation - only under thermal runaway - which is an electrical fault rather an expected normal gas release - so not a DSEAR issue. Hazarous area classification doens't consider gross failure of a system.

The standard covers wet lead acid batteries, VRLA and NiCad batteries.

The HSE guidance for battery charging gives a 1m hazardous area Zone 1, which is extremely conservative - but an easy distance to remember. If you calculate the hazardous area following the standard, the hazardous area will be much less.

Diesel - John is correct about EI15. This standard also says, that provided there is no mechanism for a pressure/spray release, where a material has a flash point at least 5*C more than ambient temperature then no hazardous area classification is required, as no vapour is released. The typical flash point given for diesel is a minimum of 55*C. The typical maximum ambient temperature in the UK is circa 35-36*C (yes I know 2022 saw 40*C in the UK)

So even on a hot summer day, there is about a 20*C safety margin for diesel.

Compressed air systems.

The HSE guidance on what a DSEAR assessment should consider for compressed air systems is very poor. They are not discussed in the L138 DSEAR ACOP.

Even though not flamamble, as John says, the risk with compressed air systems is the build up of water within the system (the water is a vapour in the air). If allowed to accumulate in an air receiver / pressure vessel, may then lead to internal corrosion of the pressure vessel. WHich over a long period of time leads to a pressure vessel explosive failure due to corrosion weakening the pressure vessel.

This is the reason why pressure vessels have statutory inspections unser PSSR 2000 and associated Written Schems of Examination.

From memory the BCGN doesn't discuss this, but I could be wrong.

Process Design Management Ltd

thanks 1 user thanked Ian Bell2 for this useful post.
Andrew_C on 07/08/2023(UTC)
John Elder  
#6 Posted : 04 August 2023 13:52:58(UTC)
Rank: Forum user
John Elder

Ian

There might be some confusion as to how my post was interpreted.

The follow up post and question made by mrkjd e.g. (#3 post) asked a further question about battery charging areas which I assumed was rightly or wrongly to be different to the lithium batteries mentioned in (#1 Post).

That’s why I referenced BS 62485-2 but also stated in my answer in case I had interpreted the question incorrectly (given in post #4) that this was for other than lithium type batteries. And my initial response in (Post #2) referenced DNV.GL Maritime Battery Safety Joint Development Project for Lithium batteries.

Also the original question in the feed by mrkjd was regarding compress gases such as O2/CO2/Acetylene and didn’t mention compressed air which is why I referenced the British Compressed Gas Association (BCGA) standards and not PSSR.

I try to be as accurate as possible when replying to anyone on this forum as some of the responses give in a public forum can be quite misleading.

I can only confirm a persons competence within the field of DSEAR once I have review one or two of their completed DSEAR Assessments no mater how many years experience they have  in conducting such works and no matter their purported competence.

DSEAR Assessments to various levels of competence pass under my nose upon a daily basis, some completed by Senior Process Engineers, some by Health and Safety Consultants from CMOSH qualified downwards, and many other independent consultants and assessors.

Most I am afraid are not worth the paper that they are written on. But that’s only my personal opinion based upon my current knowledge level of the subject matter and my experience within this field, and it may transpire that I too am a DSEAR Dabbler suffering heavily from the Dunning Kruger effect.

Edited by user 04 August 2023 15:17:29(UTC)  | Reason: spelling correction

mrkjd  
#7 Posted : 05 August 2023 12:48:08(UTC)
Rank: Forum user
mrkjd

Gents. All replies have been useful and clear. When we arrange a DESEAR RA should we expect it to mention lithium batteries/ battery charging / gas cylinders as falling under the scope of DSEAR as hazmats and reference arrangements as per standards quoted? Or would a DSEAR assessor consider them out of scope and covered under other regs and RA processes?
John Elder  
#8 Posted : 05 August 2023 19:27:49(UTC)
Rank: Forum user
John Elder

mrkjd

When you arrange for the DSEAR Risk Assessment as the client it is up to you to set the scope of works. Most clients tie the DSEAR Assessors hands by only asking them to look at what the client thinks is a DSEAR Issue.

When my clients ask what they should be looking for regarding generating a quotation I tell them to let the assessor loose and quote for the whole site to be assessed. That’s every room in every building and every area inside and outside on site. This might seem excessive, but it is a very quick process for a competent assessor for clearing off what will probably be 99% of the areas upon site as non-hazardous and ensures that they pick up and address all possible areas with an issue.

The report then states that the whole site was surveyed but only the areas of concern are shown within the report. You can list all the buildings and areas inspected in the executive summary and then show which were non-hazardous regarding DSEAR Explosion Risk or DSEAR Increased Fire Risk and which areas were hazardous.

peter gotch  
#9 Posted : 06 August 2023 10:29:54(UTC)
Rank: Super forum user
peter gotch

Hi mrkjd

Why not take the specific legislation out of the equation?

You shouldn't really be THAT bothered about whether activity X is subject to DSEAR or not, but rather assess the risks and mitigate them "so far as reasonably practicable".

If you do that assessment and activity X is subject to DSEAR you can comply with the requirements of DSEAR without even mentioning the acronym!

Nothing in DSEAR says that the risk assessment has to be entitled "DSEAR assessment" so why not simply refer to it as "Risk Assessment for whatever scope you define"? 

So, the risk assessment(s) for activity X could be a single assessment that considers ALL the risks of activity X or a fire and explosion risk assessment (and thence DSEAR assessment) for activity X or a fire and explosion risk assessment for activity X within a wider context or various other options.

John Elder raises the broader issue of scope.

Clients don't like "scope creep" as it has a tendency to have risk of budgets going out of the window and so need control mechanisms.

Some Consultants/Contractors operate on the basis that scope creep is what makes the difference between breaking even and making a healthy profit, partly as when scope creep happens the Consultant/Contractor already appointed is likely to be an a bidding list of one for any "additional works".

I wrote "Some" not "All" and I am certainly not suggesting that John might be amongst the "Some".

I do think that it makes sense to broaden the scope of an initial DSEAR or whatever assessment so that the assessor looks at the broader picture of what is around EACH activity X.

But the potential for "scope creep" can be managed by splitting the assessment into parts. An initial sweep, a report on a scoping study and then the Client has the choice to ask the Consultant/Contractor to now make proposals for such further work as the Client deems appropriate having received the scoping study report or the Client has the choice to now go out to tender.

It might well be that the scoping study report poses questions about whether the competencies of the Consultant/Contractor are sufficient for what is needed for part or all of what is needed next.

As example the scoping survey might indicate that a need a fire suppression system for areas A, B and C, which might be entirely separate or interlinked systems. The Client may not need their initial "DSEAR or whatever" assessor for this, but rather a Contractor who can do a bespoke design and installation, possibly with a separate contract for someone to do the contract administration to oversee that the fire suppression Contractor does what it has said on the tin.

Might be that the Client ALSO needs more detailed "DSEAR or whatever" assessment of other areas which might be procured in parallel with the fire suppression system(s). 

Horses for courses. 

 

John Elder  
#10 Posted : 06 August 2023 19:34:35(UTC)
Rank: Forum user
John Elder

Once again sensible words from Peter.

Identify what you want to achieve in concept then draft a scheme of requirements or scope of works. This in itself can be sometimes the hardest part of the exercise if you have no experience and do not know what exactly what you want.

I suppose to try and prevent scope creep a simple scope of works SAMPLE would be but not restricted to as follows:

Identify any substance upon site being stored, manufactured, processed, or handled in such a way and in sufficient quantity which could pose a hazard pertaining to DSEAR explosion or DSEAR increased fire risk.

Identify the properties for those substance identified as relevant e.g. flash point, boiling point, vapour pressure, lower and upper flammable limits, auto ignition temperature and reactivity to other incompatible substances.

Identify sources of release, the type of release (continuous, primary, secondary) and their extent.

Identify availability and effectiveness of ventilation (natural or artificial), or housekeeping methodologies which might reduce the extent or potential for a hazardous zone to be formed or created.

Identify potential ignition hazards which might become effective.

Identify the consequences of an ignition.

Classify any uncontrollable releases not able to be classified as non-hazardous into their relevant hazardous zones showing all calculations, computational modelling results or standard models referenced to support the applied hazardous classification.

Create and provide any hazardous area classification drawings in plan and elevation layout for the hazardous zones identified.

Provide recommendations for compliance and management of risks identified such as suitable signage, ATEX equipment requirements, training, emergency procedures, maintenance requirements, management of change, permits to work and safe operating procedures.

mrkjd  
#11 Posted : 07 August 2023 11:04:08(UTC)
Rank: Forum user
mrkjd

Thanks all for the contributions. It seems to me that for our activities:

  • We need to conduct a specific DSEAR RA
  • This DSEAR RA needs to be conducted by a contracted specialist
  • The scope of the DSEAR will be in 2 stages
  • Where DSEAR explosion and/or DSEAR increased fire risk is identified a Stage 2 RA shall be carried out
  • Where Stage 1 RA identifies building mitigations such as establishing Haz Zones / ATEX under the Stage 2 then the establishment Responsible Person shall be notified to provide agreed mitigations

How do we establish that a substance properties combined with it's quantity raise the risk from being covered under a "normal" RA and one that falls under DSEAR as DSEAR does not specify where this happens and neither do COSHH RA / SDS. 

John Elder  
#12 Posted : 07 August 2023 11:49:20(UTC)
Rank: Forum user
John Elder

Various standards such as Energy Institute EI15 lays out minimum threshold values for gases, liquids and liquified gases used indoors or outdoors where DSEAR Assessment might need to be considered, that is why you should use a competent assessor.
Even some situations outside these values will pose a DSEAR RIsk in how they are being used.

Edited by user 07 August 2023 11:50:11(UTC)  | Reason: Not specified

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