DNV2.7-1 or DNV2.7-3? How to choose?

What is DNV certification?
DNV (Det Norske Veritas), a Norwegian classification society, merged with Germanischer Lloyd (GL) in September 2013 to form the world's largest classification society DNV GL Group.
 As a classification society, DNV GL sets standards for the offshore, maritime, energy and oil and gas industries. The purpose of these standards is to provide users, operators and engineers with requirements, principles and acceptance criteria.

Two common standards are:

• DNVGL-ST-E271, Offshore containers (2.7-1)
• DNVGL-ST-E273, Portable offshore containers (2.7-3)

 
DNV2.7-1 and DNV2.7-3 in common

• Both 2.7-1 and 2.7-3 are standards specify requirements and recommended practice covering transport of offshore containers and portable offshore containers.
• The standards cover the specific areas of design, manufacturing, testing, certification, and periodic inspection
• Both standards cover the lifting frames or containers and, in most cases, not the equipment contained within the frames
• Both standards cover the safe lifting and handling of offshore containers and installations between two floating vessels and between vessels and fixed or floating offshore installations.

 
Difference between DNV2.7-1 and DNV2.7-3
Apart from the difference in standard details, the biggest difference is that the maximum gross weight (MGW) of dnV2.7-1 certified container is less than 25,000 kgs, and the MGW of DNV2.7-3 certified container is greater than 25,000 kgs.
 
Although DNV2.7-1 and DNV2.7-3 standards are set by DNV Classification Society, they are also recognized by other classification societies (BV, LRs, etc), which will issue corresponding certificates according to the same standards.

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