CE Design Categories A–D for Yachts Under 24 m

Who assigns them and how · Estimated distribution for 65–78 ft cruising catamarans · Other classification systems · What designers actually design for

1. The four design categories (recap)

The categories come from the EU Recreational Craft Directive 2013/53/EU (successor to 94/25/EC), which applies to pleasure craft with a hull length of 2.5–24 m. They describe design conditions — the wind and sea states the boat is engineered to withstand — not legal limits on where it may travel.

Category	Name	Wind (Beaufort)	Significant wave height
A	Ocean	> Force 8 (> ~40 kn)	> 4 m
B	Offshore	up to Force 8 (≤ ~40 kn)	up to 4 m
C	Inshore	up to Force 6 (≤ ~27 kn)	up to 2 m
D	Sheltered waters	up to Force 4 (≤ ~16 kn)	up to 0.3 m (occasional 0.5 m)

Reference: Force 8 = 34–40 kn; Force 6 = 22–27 kn; Force 4 = 11–16 kn. Wave heights are significant wave height (H⅓). Boats of 24 m hull length and over fall outside the Recreational Craft Directive and are governed by classification-society and flag-state rules instead.

2. Who decides the category — and how

Short answer: The manufacturer (or the importer who places a non-EU boat on the EU market) chooses the target category and declares conformity. For Category A, an independent notified body must verify compliance; for Category B, verification is required unless harmonised standards are applied in full; Categories C and D are normally self-certified.

The process

Design brief: the builder and naval architect select a target category as part of the design specification. It drives structural loads, stability criteria, freeboard, downflooding angles, cockpit drainage, window strength, and more.
Design to harmonised ISO standards: compliance with the Directive's "essential requirements" is normally demonstrated via harmonised standards, e.g. ISO 12215 (hull construction — part 7 is specific to multihulls), ISO 12217-2 (stability & buoyancy of sailing boats, with multihull-specific criteria), ISO 12216 (windows and portlights), ISO 11812 (watertight/quick-draining cockpits), ISO 14946 (maximum load), ISO 14945 (builder's plate), ISO 10240 (owner's manual).
Conformity assessment: the manufacturer compiles a technical file and follows one of the Directive's modules (A, A1, B+C, B+D/E/F, G, H; plus Post-Construction Assessment for individual non-compliant boats). Category A always requires a notified body; Category B can be self-certified (Module A) only if harmonised standards are applied in full; Categories C and D are usually self-certified.
Marking & documentation: the boat carries a CE mark and a builder's plate stating the design category, maximum number of persons and maximum load; the manufacturer issues a Declaration of Conformity, and the owner's manual must explain the category.

Who verifies and enforces

Notified bodies (e.g., IMCI, HPiVS, RINA, DNV, Lloyd's Register, Bureau Veritas) audit, test and issue certificates for Category A boats (and for B when harmonised standards are not fully applied).
National market-surveillance authorities can inspect boats and documentation and order recalls for false or unsupported declarations.
The category is therefore a manufacturer's declaration backed by a technical file — not an award granted by a regulator — but declaring a category the boat does not actually meet is a legal non-compliance.

Important nuance: the category is a set of design parameters, not a permission or a guarantee. Category A does not make a boat safe in all oceans, and many Category B boats have crossed oceans. Seamanship, loading, maintenance and preparation matter at least as much as the label.

3. Estimated distribution for 65–78 ft cruising catamarans

Caveat: No official registry publishes these statistics. The figures below are informed estimates based on the typical certifications of mainstream models in this size range (e.g., Lagoon, Fountaine Pajot, Bali/Catana, Privilege, Sunreef, Leopard, Outremer, Gunboat, HH, Aquila, Horizon). Individual models — and even individual production years — can differ, and some models carry different ratings depending on passenger/load limits. Always check the specific boat's Declaration of Conformity and builder's plate.

Category	Estimated share of 65–78 ft cruising catamarans	Typical cases
A	≈ 80% (plausible range ~70–90%)	The large majority of mainstream sailing cruising cats; buyers in this size expect ocean capability and builders certify accordingly.
B	≈ 18% (plausible range ~10–25%)	Some power catamarans and coastal-oriented models; some boats rated B at higher passenger/load limits (dual ratings exist, e.g., A with fewer persons / B with more).
C	≈ 0–3%	Rare at this size; occasionally coastal/charter-specific or houseboat-style designs.
D	≈ 0%	Essentially nonexistent for 65–78 ft cruising catamarans.

If only sailing cruising cats are counted, the Category A share is higher still (roughly 85–90%); power catamarans account for most of the Category B share.

4. Other classification systems

Classification-society yacht class (voluntary under 24 m): Bureau Veritas, RINA, Lloyd's Register, DNV and ABS offer yacht classification with their own notations and survey regimes. Some builders of large cats optionally class their boats — more common for power cats and for boats near or above 24 m.
Commercial/charter codes: charter operation usually requires a flag-state small-commercial-vessel code — e.g., the UK MCA Code (MGN 280) with its own operating-area categories 0–6 — or an equivalent (Marshall Islands, BVI, French commercial regulations, etc.). These can be more demanding than the RCD (liferafts, bilge pumping, crew limits, survey regime).
Racing categories: World Sailing's Offshore Special Regulations (OSR) define Categories 0–4 (trans-oceanic down to inshore) for race seaworthiness and equipment — a separate system from CE categories.
Non-EU national systems: the US has no design categories; ABYC standards and NMMA certification play a similar technical role. Older national systems (e.g., the former French 1st–4th navigation categories based on distance from a safe haven) were superseded by the CE system in the EU.
Marketing terms: "blue water", "ocean-capable", "expedition" and similar phrases are unregulated and may or may not correspond to Category A.

5. What most designers of 65–78 ft cruising catamarans design for

CE Category A is the default benchmark for sailing cruising cats in this size: the market expects transocean capability, charter fleets demand it, and resale values benefit.
Technical basis: ISO 12215-7 (multihull scantlings) and ISO 12217-2 (stability/buoyancy with multihull-specific criteria — resistance to wind-induced capsize, flotation when swamped, and the RCD requirement for an escape route from an inverted habitable multihull). Many designers exceed the minimums and/or work to classification-society rules (BV, RINA, DNV) with FEA of the global structure — crossbeam/connecting-structure loads, bridgedeck slamming, rig and rudder loads dominate at this size.
Category B is chosen deliberately for some power cats and coastal-oriented models; Categories C and D are effectively not targeted in this size range.
Charter-oriented designs are frequently engineered simultaneously for a commercial code (e.g., MCA MGN 280 Category 1–2), which shapes watertight subdivision, bilge systems, freeing ports, liferaft stowage and crew limits.
Designers treat the category as a floor, not a ceiling: the heavy-weather behaviour of a big cat depends on much more than the label — bridgedeck clearance, daggerboards vs. mini-keels, sail-plan manageability, and how the boat is loaded and driven.