What is ISO 12217‑3 - Stability and buoyancy assessment about?
ISO 12217 is an international standard on stability and buoyancy assessment and categorization that discusses the required test methods for the stability and buoyancy of intact (i.e. undamaged) boats. ISO 12217-3 is the third part of a series of documents on stability and buoyancy assessment and categorization. ISO 12217‑3 specifies methods for evaluating the stability and buoyancy of intact (i.e. undamaged) boats. The flotation characteristics of craft susceptible to swamping are also encompassed.
The evaluation of stability and buoyancy properties using this part of ISO 12217 will enable the boat to be assigned to a design category (C or D) appropriate to its design and maximum load.
ISO 12217‑3 is applicable to boats of hull length less than 6 m, whether propelled by human or mechanical power, except habitable sailing multihulls. Boats of hull length less than 6 m which are fitted with a full deck and quick-draining cockpit(s) complying with ISO 11812 may alternatively be assessed using ISO 12217-1 or ISO 12217-2 (for non-sailing and sailing boats, respectively), in which case higher design categories may be assigned.
In relation to habitable multihulls, this part of ISO 12217 includes assessment of susceptibility to inversion, the definition of viable means of escape, and requirements for inverted flotation.
ISO 12217‑3 excludes:
- Inflatable and rigid-inflatable boats covered by ISO 6185, except for references made in ISO 6185 to specific clauses of ISO 12217
- Personal watercraft covered by ISO 13590 and other similar powered craft
- Aquatic toys
- Canoes and kayaks
- Gondolas and pedalos
- Sailing surfboards
- Surfboards, including powered surfboards
- Hydrofoils, foil stabilized boats, and hovercraft when not operating in the displacement mode
- Submersibles
Who is ISO 12217‑3 - Stability and buoyancy assessment for?
ISO 12217-3 on stability and buoyancy assessment and categorization is relevant to
- Sailing boats, ships manufacturer
Why should you use ISO 12217‑3 - Stability and buoyancy assessment?
Intact Stability. This field of study deals with the stability of a surface ship when the intactness of its hull is maintained, and no compartment or watertight tank is damaged or freely flooded by seawater.
ISO 12217-2 provides guidance on maximum load, sailing or non-sailing, tests, calculations and requirements to be applied, variation in input parameters, requirements for monohull boats, requirements for catamarans, trimarans, and form-stable monohulls.
As a user of ISO 12217-3, you can be ensured of methods for evaluating the stability and buoyancy of intact boats. With obedience and compliance to ISO 12217-3, you can efficiently maintain the stability of a surface ship. With ISO 12217-3 you can be ensured of all test methods and calculations on stability and buoyancy assessment and categorization.
What’s changed since the last update?
BS EN ISO 12217‑3:2017 supersedes BS EN ISO 12217‑3:2015, which is withdrawn.
This third edition cancels and replaces the second edition (ISO 12217-3:2013), of which it constitutes a minor revision. It incorporates the following modifications:
- Introduction and Clause 9.2: the reference to the European Directive has been updated (2013/53/EU)
- Clause 1, subclauses 6.2, 6.3.1.5 d) 3) and F.2 g): vulnerable has been replaced with susceptible
- Clause 3: definitions 3.1.1, 3.3.5, and 3.4.9 have been amended
- Annex H: worksheets 2, 4, 6, 8, and 15 have been corrected to align with corrections listed above
- Annex I has been added
- Bibliography: reference to ISO 7010 has been added
- Editorial and cross-referencing corrections have been made to definitions 3.2.2 and 3.2.3 and subclauses, 6.4.1, 6.4.2.1, 6.4.2.2 and 6.4.2.3, to Table G.2, and Annex H, worksheet 6

