Radon in Giants

[Lankyman]

From this thinking the absolutely perfect storm for both factors would be for someone to be a smoker who spends a long time digging in Giant's Hole eating bacon sandwiches

Whatever you do, don't have a bowl of Readybrek before going down!

 

[mikem]

No'one has answered my question about draughts. Simplistically, it would seem reasonable that draughty caves would have less radon than those with still air. Are there any data to support or refute this idea?

Bob, further up same page, pointed out that ventilation makes a difference, but different caves have different radiation levels in different parts at different times of year - the weather also affects matters, high pressure systems pushing air inwards, whilst low pressure sucks it out - caves with a chimney effect across two (or more) entrances will be best at getting rid of radon

 

[wellyjen]

No'one has answered my question about draughts. Simplistically, it would seem reasonable that draughty caves would have less radon than those with still air. Are there any data to support or refute this idea?

The show cave owners seem to think so. Peak Cavern has the fan in Cavedale Vent. Speedwell has fans and also the trap door at the top of the climb from Leviathan to the Boulder Piles to control air flow. Their guides spend many hours underground, so cumulative exposure would be an issue, as it would for PICA members. I have no idea what measurements they have had done and that would again be commercially confidential information and certainly not something they would want publishing.

 

[mikem]

Conversely if levels are highest in chambers away from the entrance(s), air pressure may just mostly move it into adjacent areas and then back again. It's one reason why many showcaves have created additional entrances (& fans always working in one direction - although they need to be at pinch points - in large chambers they'll just cause circulation)

 

[Cantclimbtom]

Conversely if levels are highest in chambers away from the entrance(s), air pressure may just mostly move it into adjacent areas and then back again. It's one reason why many showcaves have created additional entrances (& fans always working in one direction - although they need to be at pinch points - in large chambers they'll just cause circulation)

There's a heap of accumulated knowledge from coal mining that show cave owners and HSE benefit from, not just for the "nasties" (damps) with coal, but Radon also.

 

[LJR]

From a mining point of view, the cure for Radon is either more ventilation or reduced exposure, or both.
We had a Radon problem at my previous mine and had to completely re-arrange the ventilation circuit to get more air into the further districts. Some distant parts of the mine were taken off limits and access restricted to short duration inspection only.
Obviously it is not so easy to ventilate a single entry cave!

 

[mikem]

Showcaves and active mines also have much more oxygen being turned into carbon dioxide (so maybe those plants growing under artificial light do help!)

 

[Cantclimbtom]

Showcaves and active mines also have much more oxygen being turned into carbon dioxide (so maybe those plants growing under artificial light do help!)

So the conclusion is that Giants should have a second entrance added for airflow, possibly "mechanical ventilation" (some fans) and maybe electric lighting fitted throughout to encourage plants. Rightiho I'll pen a quick letter to Derbyshire County Council.

 

[andrewmcleod]

White Scar is ventilated by a fan when the air temperature is above(?) some critical temperature. At the western end of the Battlefield there is a wooden partition across the cave with a big fan in, then further along there is a borehole from the surface that's maybe 20cm diameter? It's quite an impressive draught when it's running. I presume the air then flows down past Big Bertha and into the lower show cave that way (since there is a door on the Battlefield steps).

 

[wellyjen]

So the conclusion is that Giants should have a second entrance added for airflow, possibly "mechanical ventilation" (some fans) and maybe electric lighting fitted throughout to encourage plants. Rightiho I'll pen a quick letter to Derbyshire County Council.

Some of the concrete steps are already in, so the rest shouldn't take long.

 

[mch]

Readers of this thread might be interested in the report on radon monitoring considered and agreed by DCA Council at the AGM on 14th March - copy attached.

 

[cap n chris]

Project Pandora perhaps.

 

[alanw]

Whatever you do, don't have a bowl of Readybrek before going down!

Not the Nine O'Clock news spoof: "Do you want your kids to glow in the dark? Move to Windscale."

 

[pwhole]

So the conclusion is that Giants should have a second entrance added for airflow, possibly "mechanical ventilation" (some fans) and maybe electric lighting fitted throughout to encourage plants. Rightiho I'll pen a quick letter to Derbyshire County Council.

I'd send one to the owner of that collection box in the first instance

 

[Jenny P]

Worth noting that some French show caves actually have airlock double doors, both at the entrance and separating different areas of the cave, specifically to prevent draughts and restrict the airflow. This seems to be on conservation grounds, i.e. to prevent changes in the cave microclimate which might affect either specific formations or maybe cave life. I came across this in the Vercors and was quite surprised, remembering radon issues in the UK.

Don't know if the same situation applies in other French show caves or in show caves in other countries.

 

[mikem]

Radon is more prevalent in volcanic rocks (hence living in Cornwall being an issue), super heated water carried the lead into other areas (Peak District has much deeper deposits than, for example, Mendip - hence they were more important earlier on, as closer to surface. Don't know about North Pennines). Here is a french map:

https://research-assessment.asnr.fr/sites/en/files/2024-01/Expo_radioactivity_v2023_EN_3_Radon.pdf

 

[langcliffe]

Radon is more prevalent in volcanic rocks (hence living in Cornwall being an issue), super heated water carried the lead into other areas (Peak District has much deeper deposits than, for example, Mendip - hence they were more important earlier on, as closer to surface. Don't know about North Pennines). Here is a french map:

https://research-assessment.asnr.fr/sites/en/files/2024-01/Expo_radioactivity_v2023_EN_3_Radon.pdf

I understand that the radon problem in Cornwall results from the intrusive igneous rocks, rather than from the volcanic rocks.

 

[mikem]

Igneous rocks are volcanic, the only difference is whether they cool above or below the surface (okay, I suppose to be truly volcanic then they have to erupt)

 

[langcliffe]

Igneous rocks are volcanic, the only difference is whether they cool above or below the surface (okay, I suppose to be truly volcanic then they have to erupt)

Quite.

 

[mikem]

However, it's the same stuff (presumably actual volcanic releases more of the radon into the atmosphere, whilst granite / gabbro stores it below the surface)