Tables and Hard work underwater

[eternaljonah]

the other day we did some reef cleaning like we do a lot here to get the fishing nets of the reef. the reef is about 30mt deep. so time flys, and the dive is very close to the ndl, try not to get into deco on these dive's What i'm wondering is most tables are made for recreational diving and when you do serious exercise or work your body pumps more oxygen to the muscle so more nitrogen too? then when you are on the way up you are no longer working so the blood flow to the muscles is less making is harder to off gas. how would you calculate dive time and ndl for a dive where one was physically active. there is always the possibility( as we mostly do) of doing the 5mt safety stop on nitrox 50 and doing it for 5min or more but that's all just adding safety. how would one Calculate thanks

then a P.S. if this hard work was done on a mix of lets say nitrox 32 would there be higher risk of cns toxicity as the body is absorbing more oxygen ?

 

[rhwestfall]

Isn't it (okay, wasn't it) standard practice to either calculate the dive at a deeper depth or to back off pressure groups when dealing with either cold water or strenuous conditions? What do you teach your students?

 

[DevonDiver]

As Bob said... re-visit your Open Water manual.

 

[dumpsterDiver]

Isn't it (okay, wasn't it) standard practice to either calculate the dive at a deeper depth or to back off pressure groups when dealing with either cold water or strenuous conditions? What do you teach your students?

This is incorrect. The recommendation was to pick the next greater depth and time.

 

[rhwestfall]

my syntax may be incorrect, and thank-you for that correction, but backing off a pressure group was meant in a way to calculate your dive in excess of actual.

i.e.: end as a "d" -> then consider as an "g" or "h"....

example: 70' for 27 min = "m", next step is 80' for 27 min = "p" (Padi Table from OW Manual)

10' deeper equates to backing off 3 pressure groups.....

 

[DevonDiver]

Duplicate post

 

[DevonDiver]

This is incorrect. The recommendation was to pick the next greater depth and time.

I guess agencies have different recommendations. The PADI RDP states: "When planning a dive in cold water or under conditions that might be strenuous, plan the dive assuming the depth is 10ft deeper than actual".

It's under General Rules...

 

[dumpsterDiver]

I think that I will have to conceded that I AM WRONG. Sorry about that..

 

[eternaljonah]

sure that is the answer given by padi in the open water manual. but they also say that wave's break when the distance to the ocean's bottom is half it hight, or when temperature changes 1 degree in a tank pressure changes is 0.6 bar( real formulas are a little hard for the rec diver). Any way i was not asking this question is regard to Padi and recreational open water dive's but in the Tech forum, in relation to some diver's whom many have spent time clearing/lifting or doing other work with heavy objects, and how they calculate.