Matching GF between main and backup computers?

[stuartv]

I keep my primary on my "real" GF settings and my backup set to 95/95.

If something happens that I want to get out of the water as quickly as safely possible, I just refer to my backup and don't have to futz with changing any settings.

 

[JoeTPhilly]

The instructor suggested this for your Fundies class? Did you take fundies to be able to take Tech 1? Maybe it was in preparation for that? My instructor didn't even mention GFs in my class.

If I remember correctly it was another GUE diver who was helping out. I don't think the instructor mentioned anything regarding GFs.

 

[grantmac]

I keep my primary on my "real" GF settings and my backup set to 95/95.

If something happens that I want to get out of the water as quickly as safely possible, I just refer to my backup and don't have to futz with changing any settings.

Could just use SurfGF for that though right?

 

[tursiops]

learn the rule-of-thumb "rule of 130."

I'd like to know more about this. I was not aware there was a "rule of 130."

Info - The Rule of 120

(This is an updated version of a post made 4 1/2 years ago....) You will sometime hear divers (especially older ones) refer to the Rule of 120. this was an approximation to working out No-Decompression-Limits based on the old U.S. Navy tables. The "Rule of 120" was based on the sum of depth (in...

scubaboard.com

 

[LFMarm]

Could just use SurfGF for that though right?

No, you also need to know your ceiling and that depends on GFs

 

[steinbil]

I'd like to know more about this. I was not aware there was a "rule of 130."

Info - The Rule of 120

(This is an updated version of a post made 4 1/2 years ago....) You will sometime hear divers (especially older ones) refer to the Rule of 120. this was an approximation to working out No-Decompression-Limits based on the old U.S. Navy tables. The "Rule of 120" was based on the sum of depth (in...

scubaboard.com

It's basically the same rule, but for EAN32. So 30 minutes at 100ft, 40minutes at 90ft etc.

 

[tursiops]

It's basically the same rule, but for EAN32. So 30 minutes at 100ft, 40minutes at 90ft etc.

The PADI RDP for 32% would be a rule of 125, not 130. Even the Navy/NOAA tables don't support 130.

 

[jborg]

The PADI RDP for 32% would be a rule of 125, not 130. Even the Navy/NOAA tables don't support 130.

There are many different tables.

 

[tursiops]

There are many different tables.

View attachment 807943

?? That IS the PADI 32% RDP, and it gives a rule of 125...exact at 80 and 90 feet, conservative deeper and shallower than that.

 

[jborg]

The table says 100 ft, 30 minutes, which it seemed like you questioned the validity of.

GUE uses 30 min @ 30 m as the rule of thumb, which is the same as 30 min @ 100 ft in the PADI table. (Since that's the deepest allowed by the GUE table that forms the basis of the rule of thumb; that's not the case in the PADI table so perhaps a different rule of thumb becomes more natural.)