Does Your Sea Container Measure Up? Important Standards for Offshore Containers

Shipping containers are designed for a wide variety of purposes, but their many forms and functions must be abide by certain international standards for use around the world. Just as standards exist for common cargo containers to help with stacking, stability and safety, other standards come into play when it comes to designs and functions or offshore containers too.

These containers are meant to face a very unique set of challenges about their utility lifetime and must meet a few strict requirements to ensure they can do so. Such measures keep the potential for accidents and damages to a minimum by streamlining important aspects of each container's design. To fully understand how to handle these containers and the assortment of rules that govern their designs, it helps to have a solid grass on exactly what offshore containers are used for.

What are Offshore Containers?

Offshore containers are typically used on oil rigs and other oil-industry-related locations at sea. However, regardless of the type or purpose of an offshore structure, these containers are designed for optimal use.

Outfitted with special features such as padeyes and stackable designs, offshore containers allow workers with highly specialized equipment to handle all cargo, waste and more while observing strict security protocol.

What Types of Offshore Containers are There?

Offshore containers come in many shapes and sizes. Although the applications are many, there are three main categories that fit all offshore containers: cargo containers, basket containers and service containers. Below is a bit more information about each of these unique designations:

Cargo or Freight Containers

These types of offshore containers serve the same purpose as standard shipping containers, break away items safely and securely for transport to and from offshore facilities as well as for safekeeping on location.

There are numerous types of cargo containers, but a few are particularly common:

General Cargo Containers
These simple containers closely resemble standard shipping containers and come equipped with the usual doors / fittings. However, they are also significantly more durable than standard containers and usually come crafted from high grade steel.

Tank Containers
These types of offshore cargo containers accommodate all manner of liquids safely within a protected tank. Most containers of this child encase a sturdy tank within a steel cage to protect it from impacts and assist in stacking / space-saving. Both non-reactive and volatile fluids are often transported to and from offshore facilities in these containers.

Bulk Containers
These containers allow for large quantities or solid items to be transported and stored securely.

Special Containers
These types of containers are designed to accommodate unique items and equipment.

Baskets and Skips
These heavy-duty container variations are intended to accommodate a variety of tasks ranging from waste storage to lifting and hoisting. Offshore basket and skip containers feature open tops for easy storage and emptying.

Service Containers
These special containers serve more complex purposes than more storage and transport. Service containers are actually used to provide living spaces for workers, laboratories, workshops, galleys and more. These containers are often used alongside each other to create temporary installations on offshore platforms.

What Offshore Container Standards Exist?

There are many international standards that pertain to offshore containers. These standards provide guidelines for safe container construction that take into account all of the complexities or transport and handling such containers on land and sea. Offshore varieties are more strictly defined and regulated to prevent disasters from occurring.

Below are the primary standards that tend to govern offshore container designs:

DNV-ST-E271

Det Norske Veritas, or "The Norwegian Truth," Germanischer Lloyd (DNV GL) serves as a leading organization in charge of certifying offshore containers for commercial use. As an internationally accredited registrar, DNV GL actually certifies materials and processes in multiple industries. However, their guidelines in the oil and gas industry have standardized roughly 65% of the world's offshore installations.

The same certification standards that DNV GL applies to offshore facilities are adapted to the containers destined to be used on such. For your offshore container to make the grade, it will need to satisfy the following requirements, among others:

Exceptional Strength

Strength and durability are integral characteristics or all good shipping and storage containers. However, there is a greater need for superior strength in the context of offshore facilities. Containers intended for such purposes are required by DNV-ST-E271 guidelines to accommodate greater stress and far more extreme conditions.

At sea, such containers will be relied on during potentially dangerous moving processes. They need to be able to not only withstand impacts and movement but also hold up against heavily damaging weather conditions such as tropical storms and hurricanes.

Safe Materials

Building on the need for toughness in the face of the elements is a strong need for safe material combinations and choices. Certain materials introduce elements of risk into daily operations or offshore facilities and DNV-ST-E271 rules advise manufacturers against using them.

Containers with exposed aluminum, for instance, are often not appropriate for offshore use due to the risks of aluminum creating sparks when scratching corroded steel. Sparks on oil rigs are obvious hazards, but many other material choices introduce dangers as well. Thus, this aspect of DNV-ST-E271 certification is especially important for safety purposes.

Enhanced Stability

All containers that measure DNV-ST-E271 guidelines must be designed with ocean instability in mind. When containers are lifted from boats in deep water and moved onto offshore platforms, there is a risk that they will accidentally tip about it. General movement of the facility or transport vessel can also cause containers to capsize. To combat the issue, DNV-ST-E271 guidelines specify a need for containers to feature carefully calculated designs capable of withstanding tilts or up to 30 degrees without toppling.

EN12079

This standard differs from DNV-ST-E271 only in terms of its guidelines on periodic inspections and is considered a British Standard in status. However, just recently, this decidedly “European” standard has been superseded altogether by a more all-encompassing global standard known as ISO 10855.

ISO 10855

In form and function, the newly implemented ISO 10855 international offshore container standard matches much of its predecessor, EN12079, in terms of specific standards.

Key facets of this set of standards are a single periodic inspection schedule, mandatory inclusion of stacking fittings as well as special rules for designing top protection to cut the risk of snagging on cranes and machinery while lifting and moving.

This set of standards doesn't deal with intricacies or repair and general use of offshore containers but clearly lays out ground rules for their manufacture and inspection.

How to Tell If Your Containers Are Certified for Offshore Use

Since offshore containers are built to varying specifications in terms of size and shape, they are not bound to the regular CSC guidelines for shipping containers and do not contain the accompanying combined data plate that such containers are given to certify that they are compliant and usable. Instead, these types of containers should have an approval plate listing their specifications.

To fully ensure your containers are indeed DNV GL and / or ISO certified, you can request additional documentation from your chosen manufacturer. Such documentation should show that the designs of their containers have been certified by an approved, competent authority before manufacturing. It should also show that the complete manufacturing process or at least one container was overseen by an authority as well. Finally, it should confirm that at least one prototype of the container passed the various tests it was subject to.

The tests that compliant offshore containers need to be relatively simple but they effectively prove a container to be worthy of use in the extreme conditions offshore facilities face. The three main tests are the following:

The 4-Point Lifting Test
This test involves filling the container with more than twice its allowable weight and attempting to lift it with a lifting sling.

The 2-Point Lifting Test
This test requires that the container be filled to 50% more than its allowable load and lifted at two diagonal corners.

The Vertical Impact Test
The last of the three main tests involves suspending a full container at an inclined angle over a hard surface and releasing it.

The objective of these tests is to verify that the container suffers no serious or permanent damage from the stress it is put under. Containers that pass these tests are considered significantly stronger than standard shipping containers and safer to use in dangerous environments.

Offshore sea containers are the strongest containers on the market and are fit for the most challenging applications. Armed with the information above, you should be able to verify that any offshore containers you may want to acquire are every bit as tough as you need them to be.

To learn more about the options we have available at CBOX Containers, get in touch or give us a call at 1800 433 455