Overview
EN ISO 11812:2024 (identical to ISO 11812:2020 adopted by CEN) covers requirements for watertight and quick‑draining recesses and cockpits in small craft up to 24 m load line length. The standard defines watertightness criteria, draining times, and companionway sill height requirements for recesses (including those in elevated parts of a craft). It applies to gravity drainage only (not pumps) and addresses normal operation - unattended‑craft scenarios are out of scope. The standard does not prescribe recess size, shape or location, nor does it replace stability and buoyancy requirements (see ISO 12217 series).
Key Topics and Requirements
- Watertightness and draining time - Clauses specify how recesses must resist ingress and how quickly gravity drainage must remove retained water.
- Companionway sill heights - Minimum sill requirements and measurement methods are provided to limit flooding risk.
- Quick‑draining recess classification - Includes provisions for recesses “open to the sea” and those with a reduced risk of flooding.
- Drain design and installation - Number, dimensions and placement principles for single‑bottom and multi‑bottom recesses; special provisions for foot basins.
- Calculation methods - A full normative calculation method (Annex A) and a simplified assessment method are included to verify draining times and drain sizing.
- Supporting material - Annex B (technical background), Annex C (example recesses) and requirements for information to be included in the owner’s manual.
- Normative references - Links to related standards such as ISO 8666 (principal data), ISO 12216 (windows/hatches watertightness), ISO 9093‑1/2 (seacocks), and ISO 12217 (stability and buoyancy).
Applications - Who Uses This Standard
- Naval architects and boat designers - for specifying recess and cockpit drainage and sill details during design.
- Boatbuilders and OEMs - to ensure recessed spaces and companionways meet CEN/ISO requirements for product conformity.
- Component manufacturers - for drain fittings, scuppers and companionway hardware design and testing.
- Surveyors, certification bodies and regulators - to assess compliance for recreational craft under European adoption (EN ISO 11812:2024).
- Operators and owners - owner’s manual recommendations in the standard inform safe operation and maintenance practices.
Related Standards
EN ISO 11812:2024 is essential for compliance and good practice in small craft design where watertightness and rapid gravity drainage of recesses affect safety and vessel operability.
