EN ISO 12217-1:2025 PDF

Overview

EN ISO 12217-1:2025 - Small craft: stability and buoyancy assessment and categorization (Part 1) provides standardized methods to evaluate the stability and buoyancy of intact (undamaged) non-sailing boats with hull length ≥ 6 m. The document covers flotation characteristics for boats susceptible to swamping and enables assignment of a design category (A, B, C or D) appropriate to the craft’s design and maximum total load. It is principally applicable to human‑ or mechanically‑propelled boats from 6 m up to 24 m, with limited application to some boats under 6 m that cannot reach desired categories under ISO 12217‑3.

Key topics and technical requirements

This standard defines tests, calculations and acceptance criteria for intact-boat stability and buoyancy, including:

• Downflooding: identification of downflooding openings, determination of downflooding height and angle.
• Offset‑load testing: procedures to verify reserve stability under asymmetric loads.
• Resistance to waves and wind: assessment methods for roll and wave-induced responses.
• Heel due to wind action: calculation approaches and pass/fail requirements.
• Recess size and retention for quick-draining features, with simplified and direct calculation methods.
• Flotation requirements and inverted flotation: including special provisions for habitable multihulls (susceptibility to inversion, viable escape routes and inverted flotation requirements).
• Water detection and removal: requirements for detecting and removing accumulated water.
• Normative and informative annexes (A–K) provide full methods for downflooding height, offset‑load tests, righting moment curves, level flotation tests, flotation elements, owner manual information, worksheets and summaries.

The standard explicitly excludes certain craft types: inflatable and rigid‑inflatable boats covered by the ISO 6185 series, personal watercraft (ISO 13590), gondolas, pedalos, surfboards, hydrofoils and hovercraft when not in displacement mode, and submersibles.

Practical applications and users

SIST EN ISO 12217-1 is essential for:

• Naval architects and small craft designers - to design vessels that meet required stability and buoyancy performance and to demonstrate compliance with a design category.
• Boat manufacturers - to verify production models and support product declarations.
• Certification bodies, surveyors and regulatory authorities - for conformity assessment, classification and market approval in jurisdictions adopting the EN ISO text.
• Maritime safety consultants and owners - to understand operational limits, escape requirements, and floodability risks.

Keywords: EN ISO 12217-1:2025, small craft stability, buoyancy assessment, design category A B C D, non-sailing boats, downflooding, flotation requirements.

Related standards

• ISO 12217 series (Part 3 referenced for small boats