Just working through an interesting thought on gas for a pony cylinder... the usual statement applies that the gas there is only a redundant source, and all gas management are based on the main supply....
couple scenarios here:
1. "Air" dive, recreational limits with hard bottom - pony is also "air". Would it beneficial to instead carry an enriched mixture (say a EAN28) as a "safety cushion"? I chose EAN28 for this discussion as the MOD works for the diving I would be doing....
2. Enriched air dive - I thinking if you are diving EAN, you should then be carrying the same or richer (MOD limited) for the dive in the pony, correct (rather than "air")?
It seems that if your dive is following an EAN schedule, and that emergency showed up, you wouldn't want to be switching to air due to the potential of being out past the NDL range of the gas.
If not, I guess I also make the statement that the NDL should be based on the emergency gas too, rather than the main cylinder gas.....
Thoughts?
couple scenarios here:
1. "Air" dive, recreational limits with hard bottom - pony is also "air". Would it beneficial to instead carry an enriched mixture (say a EAN28) as a "safety cushion"? I chose EAN28 for this discussion as the MOD works for the diving I would be doing....
2. Enriched air dive - I thinking if you are diving EAN, you should then be carrying the same or richer (MOD limited) for the dive in the pony, correct (rather than "air")?
It seems that if your dive is following an EAN schedule, and that emergency showed up, you wouldn't want to be switching to air due to the potential of being out past the NDL range of the gas.
If not, I guess I also make the statement that the NDL should be based on the emergency gas too, rather than the main cylinder gas.....
Thoughts?