differences between DNV RP E305 and DNV RP F109

[mimouscha]

Hello you guys, I would like to know what are the differences between the two recommanded practices of DNV : DNV RP E305 and DNV RP F109.
In fact they both have the same name " on-bottom stability design of submarine pipelines" and I remarqued that DNV RP F109 is an update of the DNV RP E305, but I want to know what's the the new that DNV RP F109 has brough, and why do we still use the two versions of this recommanded practice.
Thank you.

 

[Eyeoftheneedle]

You should read the first sentence of the Introduction: "DNV-RP-F109 will replace the existing offshore design code, DNV-RP-E305 "On-Bottom Stability Design of Submarine Pipelines"."

NB this text was taken from the 2007 version.

 

[mimouscha]

That's right, but some data in the 2007 version are not clear and I think I will need to go back to the 1988 version :/
then the new version does not totally replace the ancien one