Bad fills can be real. I know we have experienced a compressor failure that made 14 people sick from CO poisoning. Now if that is the case here, I have no clue.
This is where Dandydon steps in and touts having a CO meter and I will agree with him 100%. It rules out the unknown that you can't see or smell.
I would recommend asking for their most current air sample report!
It's rare to see anyone admitting their compressor caused CO hits. Good for manning-up.
I certainly think that every fill station at every dive destination should have inline CO monitors, carefully & routinely calibrated, with autho shutoff that staff will not bypass when it interrupts their work, as if they're not that serious about the air we breath - get out and find a less serious business. It's only a matter of life and death really.
But then, the trust-me approach fails me even then. If I can't be there to see the compressor running with the CO monitor operating while my tanks are filled, I have to wonder - and banked or nurse tanks contain air blending from different times. Yeah, I think fill stations should do their part, but I'm still going to do mine and test every tank.
And then there is the real world, like Santa Rosa NM where divers from several states go to practice. Tanks are filled by a sweetheart of a lady who owns an old compressor that she and her late husband got somewhere, and she is there
every weekend, available after her day job other days on request - and many of us who don't own and want to carry 4 or more tanks each on the long trip over really depend on her for our dives - but she will never be able to add an inline monitor. My home bud used to think I was a fanatic on this CO issue (we agree to disagree on politics & religion among other things) but went along with my testing and saw his air at 5ppm the first time there. :shocked2: 5 ain't much, but where did it come from and what could it be next time? Bring the tester!! Then in Cozumel we turned a boat when we saw 17.
Current air sample reports are worthless! Oh, they may reflect that the operator is trying at least, but this ain't horseshoes and close don't cut it. However good the air sample tested from several weeks or months ago, first thing in the morning after a filter change has little to do with how good the air may be now, from a machine that has been running hard all day. So many think that air intake is everything on a compressor but a hot machine leads to a partial combustion of its own lubricating oil - maybe not enough to smell or taste, but enough to exceed CO limits. Maximum allowed is 10 ppm by the way - such a small but important number: 10 parts in 1,000,000.
I know, for an individual diver to consider spending that much money on a personal tester, something that their shop and Inst did not warn them that they needed when they started, cannot be encouraging. It's a relatively new idea to the sport, but only because the technology is very new and no one I know of was pushing the idea even a few years ago. SPGs were new once too, as were Octos and BCs. I didn't like spending $130 on my first one but the more I learned the more I realized how important. I've since had to upgrade that $130 analyzer to the correct model, along with a replacement after a dumb accident ruined one, but to make my point - I now carry it and the nicer, easier, faster Analox unit - still a bargain at $290 (Scubatoys.com).
Now why the problem originally asked in the thread?
Other than the risks of partial pressure blending Nitrox in a possibly dirty tank, I don't see it.
And if you are wondering why 10+ppm CO is serious when 300+ppm CO
2 is not...?
Even tho the CO2 results raises a flag for the Op to explore, it doesn't cause a problem in your lungs, even at depth, as long as the O2 is still around 20% - which is is.
But if the CO tests at 17ppm like we saw that day on the way to a deep site, and we had dived it to 130 ft or so as planned, that's like breathing 85ppm at depth, while working, the O2 is also at a higher PP so not so bad until you ascend - but CO binds to your blood. On ascent, the PPO drops faster than the CO bound and your risk of a hit increases. Will you remain conscious and breathing from that tank until you reach the surface and signal for help? Will help be immediate? Will you survive long enough to get on the boat's O2 kit? And as in one accident that happened in Coz year before last - what do you do when everyone on the boat comes back ill and needing O2 from that one kit? Fortunately they all survived the trip to shore where more kits and ambulances met the boat. The injuries were not fatal and while the Operator lost a profitable dock franchise, he recently gained a new one. Whether he now monitors his compressor for CO is unknown, but his new resort puts more money into advertising that fixing their continued problem with Legionnaires' infections that hardly anyone hears about, so - business continues.
I've posted several threads asking for online posting of dive reports so that folks can make themselves familiar with the reports. I don't think there is much interest though.
http://www.scubaboard.com/forums/compressors-boosters-nitrox-trimix-blending-systems/380055-does-your-shop-post-air-quality-results-online.html
It bothered me at first when I heard that Padi had quietly stopped requiring quarterly tests, doing even less to protect us, while DAN is seemingly afraid to approach this need - until I realized that a snapshot of quality 4 times a year is no assurance. I'm not going to post on your thread, but here ya go. Nice attitude, wrong direction.