John, Sorry to hear about your buddy.
Sam's post is spot on:
Another consideration:
Although Raton Pass (~7834 ft) is the highest point before entering Colorado, not everyone is aware how much of the elevation increase occurs how early. Just the trip from Santa Rosa (~4615 ft) to Las Vegas (~6450 ft) is over half the elevation gain experienced on the way to Raton Pass. But we don't notice it so much because it is pretty gradual.
Las Vegas and the City of Raton (~6350 ft) are at essentially the same elevation, and then you get the rapid increase.
Someone pointed out
this post a year or two ago. I didn't realize the difference between Santa Roas and Las Vegas was so significant!
Ron, when we lived in Colorado and made the Blue HOle trip regularly from there, we were informed several times about other local divers getting bent. They had only done dives at Blue Hole, none were deco.
It does happen. That is why our LDS always had everyone spend at least an hour in Santa Rosa before starting the drive home, then we all met at the Pizza Hut in Las Vegas for lunch for another one hour sit. Then we drove to Raton and met up at Dairy Queen for another sit of 30 minutes or so. That was our LDS safe ascent plan, making for a long drive home but safer for sure. Not everyone followed this, but we always did. The times we heard about divers ending up at the chamber, they had not followed this, one was even an instructor who drove her little sports car from BH right over the pass without any stops!
robin
That sounds like the LDS I was OW Certified by. They stress the importance of delaying the climb up Raton pass and they "forced" us to stop at the Pizza Hut in Las Vegas by not signing our log books or cert forms until at the Pizza Hut. They further suggested the ice cream stop in Ration before driving the pass.
They only stressed Raton Pass. Nothing was said or acknowledged regarding elevation gain to Las Vegas. I followed this guidance unquestioningly, without looking further into it, until either Sam or Roger (can't remember which) posted a reference to the post I referenced above. Basically, I was a "trust me" driver. Since reading the post, I always delay my departure from the Hole by casually packing up my gear, and eating lunch before departure. Lunch is often burgers and brats, cooked by Ron, so it's not a quick PB&J sandwich and hit the road.
My feeling is if I'm going to delay my arrival home, I might as well delay it at the beginning of the trip, where it might do the most good. Also, as most who have ridden with me can attest, once I hit the road, you have to ask for any stops, or it will be a non-stop trip back.
[It really is surprising and quite a concern to me how many "trust me" dives and drives I've followed, believing the instructor or DM and carefully considered my welfare prior to departing. Now, after a few hundred dives and completing my Divemaster last month, I'm realizing how naive I was.]
John, one point that was made in the thread I referenced above, was that if you made it to Las Vegas without symptoms, you were probably okay to top the pass an hour or so later. When did your buddy first show signs of DCS? Was it at Las Vegas, Raton Pass, Monument Hill (doubtful) or on his way home above Boulder?
As a side note, that I haven't taken the time to analyze yet. The last time I went to Blue Hole, I changed my computers from Salt water, Sea Level, to Fresh water, but mistakenly set it for an elevation greater than I should have. I can't recall now if I set it for 5,000-8,000 feet or for 8,000-12,000 feet. In any case, there were a couple times that I went into Deco for a few minutes, but as I came up, the Deco obligation (according to the computer) went away. I'm wondering if it might be prudent to add an extra layer of conservatism (I already set my computer as conservative as possible) and set the computer to a higher elevation (ideally, the maximum elevation you expect to obtain within the next 24-hours)? That is one way of using the RDP tables....you just plan your dives at the maximum elevation you expect to see. Any thoughts?
I sure hope we all can learn from this.
