British diver found dead - Talay Songhong park, Thailand

[DandyDon]

Have a CO detector in my boat cabin. Indeed it will go off when the boat is not underway, engines are running, no breeze so exhaust can drift up onto the boat.

What type or model works well in salt air on a boat

Boats with open back cabins are also notorious for sucking CO in while moving with the station wagon affect.

 

[DarrynSami]

Cheap residential detectors from home depot, works well for the purpose and easy to replace, test them every week or when getting underway. I replace the detector every year or so even if it is working. The detector has gone off when the exhaust was too low of concentration for me to notice the exhaust smell. You can suck exhaust into the cabin while moving in cold weather. Does not happen with a window cracked open in the cabin hence never an issue in warm weather. I've had the CO detector go off with the engines not running but a diesel fired auxiliary heater running. Anyway, I should get back on track with this thread which is CO in scuba.

 

[Dan]

...If he did use that at 150 meters, it'd be similar to 700ppm CO on the surface.

Please explain how 45ppm get to 700ppm. Gas concentration shouldn’t change as far as I know. Partial pressure may change depending upon the ambient pressure.

 

[infieldg]

Please explain how 45ppm get to 700ppm. Gas concentration shouldn’t change as far as I know. Partial pressure may change depending upon the ambient pressure.

I think they meant that the physical quantity of CO at 45ppm in each breath at depth is equivalent to a breath of 720ppm gas on the surface cos you're breathing 16x as much at depth.

 

[Hiszpan]

It continues to amaze me that anyone can get a battery-powered smoke & CO alarm at any Walmart for $20 thanks to recent technological & manufacturing advances that any boat with a partial or full cabin would not have one.

The solution is easy enough. If every customer asked to see & test the smoke & CO alarms after boarding, then got off if not pleased, the problem would be fixed. Salt air is probably hard on them, but so what. Cheaply replace often.

But then, there are homes without them. Can't fix stupid.

Cars are different as hot as the cabins get when parked in the summer, but I carry one with me.

I understand your "crusade" now, DandyDon, and I want to thank you for banging on about this subject. Had it not been for your posts under this thread, I would not have thought about CO as a cause of my problems. I never did before, blaming all other factors that I was aware of.

I did have a 30-foot boat before, and I remember seeing stickers all around the cabin about CO danger. I also had three cheap CO detectors inside the cabin of that boat. It all made sense to me this weekend.

p.s.
where I live there is no WalMart and that $20 is probably about $50-$60 here

 

[Dan]

I think they meant that the physical quantity of CO at 45ppm in each breath at depth is equivalent to a breath of 720ppm gas on the surface cos you're breathing 16x as much at depth.

Since the CO exposure limit at the surface is 50ppm, you will need to have very tight spec of CO in the diluent & bailout gas for such depth, like 1-2 ppm. Having 30-45ppm is clearly deadly.

 

[Jack Hammer]

Since the CO exposure limit at the surface is 50ppm, you will need to have very tight spec of CO in the diluent & bailout gas for such depth, like 1-2 ppm. Having 30-45ppm is clearly deadly.

Surface exposure limits have little to do with exposure at depth. Simply, CO binds on a cellular level and blocks your bodies ability to absorb O2. In a rebreather it is much worse as the CO doesnt get dilution like on the surface. For tech diving anything over 0 ppm is a no go.

 

[DandyDon]

Please explain how 45ppm get to 700ppm. Gas concentration shouldn’t change as far as I know. Partial pressure may change depending upon the ambient pressure.

45ppm at the surface taken to 150 meters and breathed at 15 atmospheres would have a PPCO 15 times as much = 670, approximately. It's the PPCO risk of diving that is so different.

It's more complicated than that and riskier since CO binds with the red cells in your blood, releasing much more slowly than PPO, so as the latter decreases, the toxicity of the former hits even harder.

where I live there is no WalMart and that $20 is probably about $50-$60 here

Where is that? It's not listed in your profile, which you might want to add for discussions like this. I actually bought my last two on Ebay for my daughter & I to use on car & overnight trips since most hotel rooms don't have CO alarms and some don't even have fire alarms.

This First Alert is shipped to most of the world, $17 USD with free shipping within the US but you can check the cost to you under details: First Alert Smoke Detector and Carbon Monoxide Detector Alarm SCO5CN 696579340175 | eBay

You need at least one in your home, one on your boat, and one for travel, but extras for backup are a good idea. Shop Ebay until you find enough.

Since the CO exposure limit at the surface is 50ppm, you will need to have very tight spec of CO in the diluent & bailout gas for such depth, like 1-2 ppm. Having 30-45ppm is clearly deadly.

I know nothing about rebreathers so I will have to bow to those who do and will post here.

 

[Hiszpan]

45ppm at the surface taken to 150 meters and breathed at 15 atmospheres would have a PPCO 15 times as much = 670, approximately. It's the PPCO risk of diving that is so different.

It's more complicated than that and riskier since CO binds with the red cells in your blood, releasing much more slowly than PPO, so as the latter decreases, the toxicity of the former hits even harder.


Where is that? It's not listed in your profile, which you might want to add for discussions like this. I actually bought my last two on Ebay for my daughter & I to use on car & overnight trips since most hotel rooms don't have CO alarms and some don't even have fire alarms.

This First Alert is shipped to most of the world, $17 USD with free shipping within the US but you can check the cost to you under details: First Alert Smoke Detector and Carbon Monoxide Detector Alarm SCO5CN 696579340175 | eBay

You need at least one in your home, one on your boat, and one for travel, but extras for backup are a good idea. Shop Ebay until you find enough.


I know nothing about rebreathers so I will have to bow to those who do and will post here.

I live in Bermuda. I have it set up on my profile as Location, but it doesn't seem to show it here

 

[DandyDon]

I live in Bermuda. I have it set up on my profile as Location, but it doesn't seem to show it here

I see that. Maybe you should report that on our help forum.