What is ISO 12217-2 - 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 12217-2 is the second part of a series of documents on stability and buoyancy assessment and categorization. ISO 12217-2 specifies methods for evaluating the stability and buoyancy of intact (i.e. undamaged) boats. The flotation characteristics of boats 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 (A, B, C, or D) appropriate to its design and maximum load.

ISO 12217-2 is principally applicable to boats propelled primarily by sail (even if fitted with an auxiliary engine) of 6 m up to and including 24 m hull length. However, it can also be applied to boats less than 6 m if they are habitable multihulls or may be applied if they do not attain the desired design category specified in ISO 12217-3 and they are decked and have quick-draining recesses which comply with ISO 11812.

About habitable multihulls, this part of ISO 12217 includes an assessment of susceptibility to inversion, the definition of viable means of escape, and requirements for inverted flotation.

ISO 12217-2 excludes:

Inflatable and rigid-inflatable boats covered by ISO 6185, except for references made in ISO 6185 to specific clauses of ISO 12217
Gondolas and pedalos
Surfboards including sailing surfboards
Hydrofoils and foil stabilized boats when not operating in the displacement mode

NOTE: Displacement mode means that the boat is only supported by hydrostatic forces.

It does not include or evaluate the effects on the stability of towing, fishing, dredging, or lifting operations, which need to be separately considered if appropriate.

Who is ISO 12217-2 - Stability and buoyancy assessment for?

ISO 12217-2 on stability and buoyancy assessment and categorization is relevant to

Sailing boats, ships manufacturer

Why should you use ISO 12217-2 - 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 12217-2, you can be ensured of methods for evaluating the stability and buoyancy of intact boats. With obedience and compliance to ISO 12217-2, you can efficiently maintain the stability of a surface ship. With ISO 12217-2 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 12217-2:2017 supersedes BS EN ISO 12217-2:2015, which is withdrawn.

This third edition cancels and replaces the second edition (ISO 12217-2:2013), of which it constitutes a minor revision. It incorporates the following modifications:

Introduction: the reference to the European Directive has been updated (2013/53/EU);

Clause 1, Clause 3, Subclause 6.3.1, Clause 9.2 updated
Subclause H.3.2 c): the coefficient in the formula has been corrected;
Annex J: worksheets 1, 2, 5, 7, 12, and 16 have been corrected to align with corrections listed above;
Annex K has been added;
Bibliography: reference to ISO 7010 has been added;
Editorial and cross-referencing corrections have been made to Table 1, Annex J, worksheets 1, 5, 7, 12, 14, and 16, and to subclauses 6.3.1, 6.3.2.2, and 6.3.2.3

BS EN ISO 12217-2:2017

Small craft. Stability and buoyancy assessment and categorization - Sailing boats of hull length greater than or equal to 6 m

Published:

31 Jan 2018

Withdrawn:

31 Oct 2025