Mild burning in my chest on O2 switch

[kierentec]

Recently on a 300ft trimix dive, I started feeling a vey mild burning sensation in my chest immediately after my switch to O2. Ascent was spot on between 28 and 32ft/min, didn't hold my breath or any other reason to suspect a lung over expansion. It was not so much painful as just really annoying. Had 27 min of deco left, so I wrote on a slate what was going on and showed it to my teammate and support divers and told them to keep an eye on me. I assured them I was ok and would let him know if it got any worse. The burning did not subside on the air breaks, but disappeared with about 3 min of hang left, and dit not return at all on the surface. It didn't feel like any kind of heartburn, acid reflux, or gas I've ever felt, and I found it strange that it started immediately after switching to O2.

Any thoughts??

 

[syntaxerrorsix]

Pulmonary oxtox symptoms can include a burning sensation in the chest/lungs with high ppo2's.

What was your total O2 exposure for the dive?

 

[wedivebc]

Was this one dive or one of a series. What was your estimated OTU accumulation?
For a one time event I would be surprised if pulmonary tox was the culprit but I have heard of people being quite sensitive to O2 exposure. I prefer to use 80% as a final deco gas and it seems my chest feels less congested after a dive but I have no scientific reason to explain why.

 

[kierentec]

Thanks guys,

I did consider pulminary oxtox, however we were well within our limits, and i have been exposed to much higher OTUs in the past with no problems. Total cns exposure for the dive was 86% it was the third day of trimix diving, the first two to a max depth 150 ft, min surface interval of 24 hours. do not recall the exact cumulative OTUs, however we were under 250 including all three dives.

 

[syntaxerrorsix]

Thanks guys,

I did consider pulminary oxtox, however we were well within our limits, and i have been exposed to much higher OTUs in the past with no problems. Total cns exposure for the dive was 86% it was the third day of trimix diving, the first two to a max depth 150 ft, min surface interval of 24 hours. do not recall the exact cumulative OTUs, however we were under 250 including all three dives.

Susceptibility to the good and bad of O2 can change daily in my opinion. Maybe a contaminated fill?

 

[kierentec]

Considered that, however I put the o2 in the bottle myself, it came from the banks we had been using all week, and went into the same cylinder I had been using all week. Who knows, I'm a smoker (I know, I know...) so that is probably a contributing factor as well...

 

[LiteHedded]

What gas were you breathing on the bottom and what were your deco gases?

 

[kierentec]

12/55 on the bottom, 32% and o2 for deco

 

[rjack321]

One thing might be that your 12/55 and 32% are fairly humid. They shouldn't be, but being in the tropics having wettish filters is certainly within the realm of plausible. The O2 being "pure" from the gas plant and cryogenically produced is inherently super dry. So the "burning" was really just a switch to really dry gas. After a time the mucus in your throat and lungs caught up with the demand to humidify the incoming gas and the burning abated.

 

[cool_hardware52]

There have been several reported cases of partial or near complete oxidation of the polymide valve seats in the tank valve on O2 bottles.

In short everything can be "clean" in your supply bottles, transfer whips, etc. and you can still have bad gas in your O2 bottle.

Have you had the gas analyzed?

Tobin