Bad Air in Long Rake Mine, Bradwell Moor

[SamT]

Speaking abou this recently with folks and I know that when there where CO2 probs in Knotlow, folks where taking gas meters in and a small pony and reg to breath off if they got into trouble.

So a couple of points. Cavers have already been to the bottom, dug, and got themselves out, so one assumes the concentrations aren't *that* high (of course this can change over time).

Also - cavers entering now should be prepared with a bottle and reg, but, it neednt be a full on 2 sidemount, double reg, reel knife affair, a small waist mounted pony would surely suffice.

 

[ian.p]

im not sure that would work the problem with CO is that it doesnt leave the blood so you cant just go ohh im feeling a bit crap ill start using the bottle because the CO will stay in your system it wont leave like CO2 which is fairly harmless in comparison in other words once youve realised youve been CO poisend it could be to late for the oxygen.

 

[Cave_Troll]

Also - cavers entering now should be prepared with a bottle and reg, but, it neednt be a full on 2 sidemount, double reg, reel knife affair, a small waist mounted pony would surely suffice.

The question is , is it a sliding scale of risk vs precautions?
If we accept that you should have BA, and that diving BA will do, this suggests that you are expecting to come across pockets of CO that you're going to sample. if your reg fails when you're in a pocket you're stuffed.
should the testers go in with two tanks and two regs?

 

[Mrs Trellis]

I'm not medical in any way but as a layman I was surprised that the symptoms became worse after exiting the cave. Did all travel in the same vehicle?

 

[JB]

Long Rake's not going anywhere and taking test gear down there won't necessarily help; it may be that the CO has dispersed now.

It seems very likely that there's a problem given what Tony has said. Let's fully investigate possible causes of this before anyone even thinks about going back into LR with or without BA kit. That may take a while but I'm sure BCA and DCA folk will do what they can to figure out if there's an obvious cause of the CO.

Jules.

 

[graham]

Speaking abou this recently with folks and I know that when there where CO2 probs in Knotlow, folks where taking gas meters in and a small pony and reg to breath off if they got into trouble.

So a couple of points. Cavers have already been to the bottom, dug, and got themselves out, so one assumes the concentrations aren't *that* high (of course this can change over time).

Also - cavers entering now should be prepared with a bottle and reg, but, it neednt be a full on 2 sidemount, double reg, reel knife affair, a small waist mounted pony would surely suffice.

Sam, you are talking about CO2, not CO. there is a qualitative difference in the risk.

 

[dl]

Also - cavers entering now should be prepared with a bottle and reg, but, it neednt be a full on 2 sidemount, double reg, reel knife affair, a small waist mounted pony would surely suffice.

The question is , is it a sliding scale of risk vs precautions?
If we accept that you should have BA, and that diving BA will do, this suggests that you are expecting to come across pockets of CO that you're going to sample. if your reg fails when you're in a pocket you're stuffed.
should the testers go in with two tanks and two regs?

Some 20 years ago two cavers entered a level in North Wales that was known to have "bad air".  As a precaution they each took some diving kit and a gas detector with them in case they had problems.  On starting to feel unwell they employed the kit they had and started to exit, they nearly didn't make it.  After the event they did some research and it appeared that the use of a standard diving reg above water was not considered adequate protection and that only a full positive pressure BA set was regarded as suitable for use in this type of situation.

I do not know what the "bad air" was in this particular case nor the technical details but I do feel that nobody should be making assumptions about what is a safe approach to entering Long Rake without seeking professional advice.

 

[Bob Smith]

Conventionally BA sets used in a situation like this are rescue sets, and can be set to on demand or full flow. The last set i used for confined space entry was a 10 minute escape set, with rescue kit available similar to this http://www.anthire.co.uk/productdetail.php?prodid=11&catid=9&level=3&PHPSESSID=ecd39225a5449ed33203beb6606e5 .The rescue sets give around 45mins of air, but if you exert yourself this will be reduced. On the point of descending into a shaft with a gas detector we typically lowered a detector in before descent and left it in situ for around 20 minutes. I would certainly be unhappy investigating this sort of thing without a serious amount of preparation, even well trained operatives would be pretty daunted i suspect.

 

[Peter Burgess]

It's odd how the danger of CO is underestimated. If these guys hadn't made it out, and a DCRO team had gone in innocently looking for some lost cavers and also suffered casualties, just think how serious the situation would have been. We should count ourselves lucky, not only that the cavers did survive, but that we have a pretty good idea what the problem was, and that nobody else has put themselves at risk.

If hypothetically there was a seriously nasty non-gaseous poison down there, like a highly radioactive source, would we be discussing how as amateurs we would be going down to try to investigate? I don't think so!

 

[Brains]

This is sounding very like a coal mining type scenario...
Traditionally and possibly unreliably a canary would be lowered down the shaft, or possibly a flame safety lamp, which I have seen used effectively by Shotlighter in Knotlow. Lowering a gas meter down carefully may be an option, but realistically without a forced draft the only viable fresh air base would be the surface, and with LR's long entrance series a free hang is not possible, so only the initial section could be pretested in this way. During out drafting the bad air may be a long way up the shaft, while conversly in drafting periods could leave the mine "fresh" for a great depth...
Glad it was good air when P bolting....

Shotlighter, any thoughts on this?

 

[nickwilliams]

Sam,

With all due respect, I think you grossly underestimate the danger of the situation, and the logistics of safely overcoming those dangers. This is not a a set of circumstances which should be responded to with the cave digger's usual 'back of a fag packet' approach - there has already been one near miss and it serves only to prove that it's not safe to tackle this without a considerable amount of care and fore-thought, as well as the correct equipment.

Bob and dl have already pointed out that those in the know do not consider SCUBA diving equipment to be safe for use in bad air locations.  I know that others on this board have used BA and in a relatively open location with no significant verticals to negotiate, the use of a band mask BA set probably doesn't present too many problems. Factor into that the need to negotiate over 100ft of rope work, as is the case in Long Rake, and the whole scenario becomes radically different.

Nick.

 

[paul]

As Nick says, there seems obvious confusion here between the effects of Carbon Monoxide (CO) and Carbon Dioxide (CO2).

Excess CO2 ("bad air" if you like) effectively lessens the concentration of available Oxygen (but also has other effects) so you get the classic symptoms: nausea, lethargy, headache. If you begin to feel symptoms then providing the CO2 levels are not too high, you can hopefully evacuate the area and recover with matbe a bad headache. With higher levels of CO2 you may fall unconscious and also possibly die.

CO combines irreversibly with the Haemoglobin in the blood. By the time you begin feeling any symptoms, it may be too late and YOU WILL PROBABLY DIE (which is why car exhaust fumes are dangerous for example and why the precursor to Natural Gas, Coal Gas, which had high levels of CO, were favourite methods of committing suicide). These cavers were very lucky.

Let those who are experts in dealing with this sort of thing investigate. Stay away until there has been an "all clear".

 

[SamT]

:chair:

OK OK - I stand corrected. I wasn't suggesting a fag packet approach, and I wasn't suggesting that folks just suck it and see (sic). I admit, until now I was ingnorant about the risk presented by CO (In that its effects are not simply eversed by getting back to fresh air).

a small waist mounted pony would surely suffice.

I asked a question and its been answered,

After the event they did some research and it appeared that the use of a standard diving reg above water was not considered adequate protection and that only a full positive pressure BA set was regarded as suitable for use in this type of situation.

so it appears diving gear is a no no.

I fully endorse a professional approach to this, that Im sure DCA/BCA will follow.

Is Jim Lister worth contacting about this, hasn't he just been on some sort of confined space rescue course with the Fire Brigade.

As to the cause,

I can only think of 3 ways in which the CO got there,
Airbourne - carried in on a draught,
Waterbourn - released from the stream way at the bottom of the mine
insitu - i.e the diggers unearthed something that was already present - and released the gas.

My concern is that if its waterbourn - could it affect bagshawe/other caves in the locale

 

[underground]

I can only think of 3 ways in which the CO got there,

Waterbourn - released from the stream way at the bottom of the mine

My concern is that if its waterbourn - could it affect bagshawe/other caves in the locale

If CO was soluble enough in water sufficient to cause toxicity, it'd be causing many problems all over the place. CO2 is magnitudes more soluble and plentiful in air, but we don't suffer the effects in the wet...

 

[braveduck]

Years ago when Moss Rake was been worked in a big way the holes being produced were being filled with rubbish in a big way.
I remember seeing large amounts of plastic waste waiting to be buldozed down a shaft,apparantly this waste had come from a plastic factory in Bradwell.
If PVC and Polystirene are in contact for a long the PVC sort of melts and generates CO.All the electric cables in my loft have melted because of poly cable clips
This problem was discoverd in modern submarines a few years back!
Is it possable the diggers have opened up an old pocket of trapped gas due to tipping on Moss Rake?

 

[LarryFatcat]

The strange thing for me is that people have been going down there recreationally for at least 40yrs and this is the first report of any problem.

This is why I would like to know more about the dig?

 

[Rob]

What would be very useful would be to know the last team down there before this incident. Maybe it was only a few weeks ago!

Last time i went down there was Summer 2007. I noticed no bad air and went too the very bottom and back. Anyone been there more recently?

 

[LarryFatcat]

A little more info on the incident. 


The group did not descend the 'Crewe' fifth pitch.

They first experienced problems in the area furthest east on the survey. (not shown in the crewe topo)

They found 'used pots and pans and blackened timbers as well as what appeared to be a hearth in the vicinity'.

The DCA 'Secretary of the Explosives User Group', is investigating.

 

[Jenny P]

Sorry Larry, but you have misunderstood in saying:  "The DCA 'Secretary of the Explosives User Group', is investigating."

I, as DCA Secretary, replied to an email you sent me, in which I simply said that the Secretary of the Explosives User Group was investigating.  The Explosives User Group is nothing to do with DCA per se.

The original warning I put out on behalf of DCA was to try to ensure that this was taken very seriously - CO poisoning is deadly.  I am satisfied that the correct course is being followed and any investigation must proceed with great care and cannot be rushed or, as someone else has said, "be subject to the "fag packet" approach. 

 

[LarryFatcat]

OK, just assumed it was part of the DCA in the context.  My fault.