DaleC
Contributor
The following is just my practice for recreational diving posted for discussion sake and not intended to be advocated for anyone elses use.
I often solo dive and part of my dive plan is having a bailout strategy both for action and equipment that I can follow should the need arise. Ordinarily recreational diving, by its definition, allows for direct accent without stops (unless you are pushing the NDL's) but I find this to be a too general "one size fits all" concept.
Along with his half pressure theory, I remember reading Haldanes thoughts (I can't remember the source but I'll link it if I can) that a diver could ascend up to, but not cross, two pressure pressure groups without incurring DCS. Crossing two PG's however was to be contraindicated. This made sense to me yet it also bugged me because in recreational diving it is quite possible to do everything "by the book" and still easily violate that measure. I looked at my style of diving and adapted some strategies as a result. I do basically two types of solo dive; shallow (< 50-60' for the duration) or deep (100'+ for a portion with a multi level ascent).
Following Haldanes concepts, I decided that if I am doing a shallow dive and need to bail I will plan to ascend directly to the surface (making a stop at 10-20' if possible). In this case I don't usually take an alternative air source as no catastrophic equipment failure will prevent a safe ascent from that CESA viable depth. In practice I have had to do this only once when I was still recovering from some sort of bronchitis and a big flem wad got stuck in my throat and I decided to ascend rather than try and pass it through my reg.
However, if I do dives that drop below 50-60' I no longer plan a direct ascent to the surface (crossing two PG's) but rather plan a direct ascent to aprox. 50' where I will stop and re evaluate my situation. This stop is akin to a deep stop for recreational depth limits and allows the effects of narcossis to lessen for proper situation evaluation. It's alsovisibly lighter (which is a factor in the PNW) and a CESA is also viable from this depth. My bailout plan is not to stay at max. depth to solve a problem if I can help it but rather to move up to my rally point (as it were) and do so there. Also, because a direct ascent is no longer relied upon as a course of action I carry a redundant air source (usually an Al40 or independant doubles). In practice I have also only had to do this once when a case of vertigo struck me at 100'. Feeling quite unstable I quickly ascended to 50' and held my position there. In that case the symptoms resolved themselves and I continued the dive at that depth.
Anyways, just some thoughts. Does anyone else have a bailout strategy that they use recreationally that varies from the "direct ascent to the surface with a 3 minute SS" rule?
I often solo dive and part of my dive plan is having a bailout strategy both for action and equipment that I can follow should the need arise. Ordinarily recreational diving, by its definition, allows for direct accent without stops (unless you are pushing the NDL's) but I find this to be a too general "one size fits all" concept.
Along with his half pressure theory, I remember reading Haldanes thoughts (I can't remember the source but I'll link it if I can) that a diver could ascend up to, but not cross, two pressure pressure groups without incurring DCS. Crossing two PG's however was to be contraindicated. This made sense to me yet it also bugged me because in recreational diving it is quite possible to do everything "by the book" and still easily violate that measure. I looked at my style of diving and adapted some strategies as a result. I do basically two types of solo dive; shallow (< 50-60' for the duration) or deep (100'+ for a portion with a multi level ascent).
Following Haldanes concepts, I decided that if I am doing a shallow dive and need to bail I will plan to ascend directly to the surface (making a stop at 10-20' if possible). In this case I don't usually take an alternative air source as no catastrophic equipment failure will prevent a safe ascent from that CESA viable depth. In practice I have had to do this only once when I was still recovering from some sort of bronchitis and a big flem wad got stuck in my throat and I decided to ascend rather than try and pass it through my reg.
However, if I do dives that drop below 50-60' I no longer plan a direct ascent to the surface (crossing two PG's) but rather plan a direct ascent to aprox. 50' where I will stop and re evaluate my situation. This stop is akin to a deep stop for recreational depth limits and allows the effects of narcossis to lessen for proper situation evaluation. It's alsovisibly lighter (which is a factor in the PNW) and a CESA is also viable from this depth. My bailout plan is not to stay at max. depth to solve a problem if I can help it but rather to move up to my rally point (as it were) and do so there. Also, because a direct ascent is no longer relied upon as a course of action I carry a redundant air source (usually an Al40 or independant doubles). In practice I have also only had to do this once when a case of vertigo struck me at 100'. Feeling quite unstable I quickly ascended to 50' and held my position there. In that case the symptoms resolved themselves and I continued the dive at that depth.
Anyways, just some thoughts. Does anyone else have a bailout strategy that they use recreationally that varies from the "direct ascent to the surface with a 3 minute SS" rule?
