Publish Time: 2026-09-28 Origin: Site
For more than two decades, PIANC Working Group 33 was one of the most widely referenced documents for marine fender-system design.
That changed with the publication of PIANC MarCom Working Group Report No. 211 — Fender Guidelines 2024.
WG211 did not simply update a few tables in WG33.
PIANC describes the 2024 document as essentially a new guideline that completely supersedes WG33.
For terminal owners, consultants, port engineers, and fender suppliers, this matters because WG211 changes how several important parts of fender design are approached — particularly berthing velocity, site-specific data, multiple-fender contact, safety, performance correction, testing, and integration with the supporting marine structure.
The transition period established for WG211 ended on May 1, 2026.
That makes 2026 an important point for project specifications still referencing WG33.
This article summarizes the main differences and what buyers should consider when preparing new marine-fender projects.
Table of Contents
PIANC WG211 is the 2024 guidance document for marine fender-system design, manufacturing, and testing.
Its objective is broader than selecting a rubber fender from a catalogue.
The guideline addresses the system needed to make berthing safe and reliable for both:
vessel
marine structure
It is mainly focused on controlled berthing of seagoing vessels, particularly where vessels are:
tug assisted
equipped with thrusters
guided by pilots
operating at designed berths
This makes WG211 especially relevant to:
container terminals
tanker berths
LNG terminals
bulk terminals
cruise berths
large commercial ports
Yes.
WG33 was published in 2002.
WG211 began as an update project, but the changes became substantial enough that the final document is treated as a new guideline.
PIANC states that WG211 completely supersedes WG33.
A transition period was provided so that fender manufacturers and project stakeholders could reorganize performance catalogues and testing around the new methodology.
That transition period ended on May 1, 2026.
Therefore, for new specifications in late 2026, simply continuing to copy older WG33 clauses without review deserves particular attention.
Because marine operations and engineering knowledge have changed.
The last two decades have seen:
larger vessels
improved berthing data
more tug-assisted operations
better understanding of actual approach geometry
improved fender testing
more detailed reliability approaches
WG211 reflects a more complete understanding of what happens when a real ship approaches a berth.
It also attempts to avoid treating the rubber unit as an isolated component.
The fender is part of a complete structure.
This is consistent with how CMR's heavy-duty Cone Fender and Cell Fender systems are used together with frontal panels, anchors, chains, and supporting structures rather than as standalone rubber blocks.
One of WG211's most important messages is simple:
Use actual site information when it exists.
Generic design values are useful when a new project has no operating history.
But existing ports may already have valuable information from:
pilots
harbor masters
tug masters
berth operators
vessel-tracking data
previous berthing studies
WG211 strongly encourages designers to use this knowledge rather than automatically taking generic values from a table.
That changes the project workflow.
Instead of starting with:
“Which PIANC velocity table should we use?”
designers should first ask:
“What do vessels actually do at this berth?”
This can produce a more realistic fender design.
Berthing velocity is one of the most sensitive inputs in energy calculation because kinetic energy increases with the square of velocity.
A small change in assumed velocity can therefore create a much larger change in design energy.
WG211 reflects more recent understanding of controlled berthing and provides updated guidance when site-specific information is unavailable.
PIANC itself notes that compared with WG33, WG211's description of the physical berthing process can result in:
higher velocities in some default cases
lower berthing angles
more recognition of multiple-fender contact
This means users should not take an old WG33 specification and simply replace the words:
“PIANC WG33”
with
“PIANC WG211.”
The underlying calculation methodology needs review.
WG211 gives more attention to the reality that a vessel may compress more than one fender during berthing.
This is particularly relevant for:
long vessels
shallow approach angles
closely spaced fender systems
Under some contact conditions, several fenders contribute to absorbing the berthing energy.
That can potentially reduce the energy demand assigned to one individual unit.
But there is another side to the calculation.
If several fenders are compressed at the same time, their reaction forces also act on the marine structure.
Therefore:
multiple fender contact may reduce required energy per fender while increasing cumulative load on the supporting structure.
This illustrates one of WG211's broader themes:
the fender cannot be designed separately from the berth.
WG211 takes a more reliability-based view of fender-system design.
PIANC notes that compared with WG33, the new approach places more of the safety consideration in the fender side of the system and requires the total marine structure to be considered integrally.
That includes:
rubber unit
frontal frame
anchors
chains
supporting structure
vessel hull
For example, selecting a Frontal Panel is not simply a matter of attaching a standard steel frame to a rubber unit.
Panel dimensions and structure need to reflect:
vessel hull pressure
fender reaction
panel bending
chain geometry
friction
vessel contact
The same principle applies to anchors and supporting quay structures.
Catalogue performance is measured under defined test conditions.
Actual projects operate under different conditions.
WG211 distinguishes the tested base performance from project-specific performance and considers correction factors such as:
velocity
temperature
angular loading
multiple-fender contact
These factors matter because rubber behavior changes with operating conditions.
Rubber response can change with compression speed.
Rubber stiffness and performance vary with temperature.
The ship may contact the panel at an angle rather than perfectly perpendicular.
Several fenders may be engaged at the same time.
A project therefore should not assume that the nominal catalogue energy and reaction values can be transferred directly into every installation without adjustment.
WG211 also places significant emphasis on:
manufacturing
testing
performance verification
type approval
This has practical implications for suppliers and buyers.
A specification should clearly state what needs to be verified rather than using general wording such as:
“Fender shall comply with PIANC.”
That statement alone may not define:
rubber compound
testing method
performance tolerance
correction factors
inspection scope
type approval
documentation
CMR manufactures marine rubber fenders together with associated steelwork such as frontal panels. For project procurement, technical requirements should therefore cover both product performance and the verification process.
No.
This is an important misunderstanding.
WG211 does not simply mean:
new guideline = larger fender.
The result depends heavily on the input data.
PIANC specifically explains that where strong site-specific information is available, the resulting fender may actually be somewhat smaller than one selected using older WG33 assumptions.
On the other hand, if local information is unavailable and conservative default values are used, the resulting design may be larger.
This is why good site information has both engineering and economic value.
Better data can reduce unnecessary overdesign while still meeting the intended reliability level.
Project owners should be cautious with specifications that were written around WG33 many years ago.
Simply editing the standard reference can create inconsistencies.
A proper review may need to revisit:
design vessels
vessel displacement
berthing velocities
approach angles
contact points
fender spacing
multiple-contact behavior
correction factors
reliability/safety approach
rubber testing
frontal-panel design
supporting structure
The scope therefore extends beyond changing a few numbers in a fender schedule.
This is particularly important for berth-upgrade projects where the vessel mix has also changed.
For a useful technical proposal, the supplier should receive enough project information to understand the real design case.
A basic inquiry package can include:
Information | Why It Matters |
|---|---|
Vessel types | Defines hull and operation |
LOA / beam / draft | Contact geometry |
Berthing displacement | Energy calculation |
Berthing velocity | Major energy input |
Approach angle | Contact behavior |
Fender spacing | Single/multiple contact |
Berth structure | Anchor and reaction design |
Temperature range | Rubber correction |
Required hull pressure | Panel sizing |
Water levels | Fender elevation |
Required standard | Testing and documentation |
Inspection requirements | Quality verification |
For complex terminal projects, a generic request such as:
“Quote 10 units of 1600H cone fender”
may not contain enough information to determine whether that fender actually fits the project.
CMR provides several heavy-duty marine fender systems, but final selection should follow the project design basis rather than a catalogue size alone.
PIANC WG211 is the 2024 guideline covering marine fender-system design, manufacture, and testing for controlled berthing of seagoing vessels.
Yes. PIANC states that WG211 completely supersedes WG33.
The transition period ended on May 1, 2026.
No. PIANC explicitly warns against this because the design approach changed substantially.
It strongly recommends using site-specific information when available, including operational knowledge from pilots, harbor masters, and tug masters.
No. The result depends on project data. Good site-specific information may produce a more optimized design than generic assumptions.
Yes. Multiple-fender contact receives greater consideration than in WG33.
Not automatically. Existing installations should be assessed according to their condition, original design basis, current vessel mix, and project requirements.
The biggest change from WG33 to WG211 is not one new table or formula.
It is the move toward a more complete representation of the real berthing system.
WG211 places stronger emphasis on:
site-specific information
realistic berthing behavior
multiple-fender contact
integrated structural design
project-specific performance
testing and verification
For port owners and consultants, that means fender selection should begin earlier in the berth-design process and involve better coordination between:
marine operations + fender supplier + structural designer + vessel requirements
For projects reviewing fender systems under current design requirements, explore CMR's Cone Fenders, Cell Fenders, Frontal Panels, or contact CMR with project data for technical discussion.