ISO 11347:2012

Overview

ISO 11347:2012 - Ships and marine technology: Large yachts - Measurement and assessment of the visual appearance of coatings specifies technical requirements and test methods for evaluating the exterior superficial coatings of large yachts. It applies to large yachts (length LH ≥ 24 m as defined in ISO 8666) used for sport, pleasure or commercial operations. The standard focuses on appearance attributes - gloss, colour and superficial defects - and describes how the final finish is to be measured and assessed prior to acceptance.

Key scope notes:

• Covers above-waterline external areas and final finish evaluation before acceptance.
• Does not address long‑term degradation of coatings or visual assessment of gelcoat.
• Allows limited edge-marking (feather-edge repairs) up to 5% of the total external coated surface under specified conditions.

Key technical topics and requirements

ISO 11347 defines parameters, definitions and measurement methods. Main topics include:

• Gloss - specular gloss measurement using a 60° gloss‑meter (referenced to ISO 2813). Annex A provides the test method.
• Colour difference - objective colour measurement and ΔE evaluation (referenced to ISO 7724 series). Annex B contains methods.
• Surface defects and texture - objective descriptions and tests for:
  • Orange peel (Annex C)
  • Fairness (visual waviness over 300–1 000 mm) (Annex D)
  • Sags (Annex E)
  • Dirt retention (Annex F)
  • Overspray (Annex G)
  • Sanding marks (Annex H)
  • Blistering (Annex I)
  • Water marks (Annex J)
  • Polishing marks (Annex K)
  • Blooming (Annex L)
• Normative references include ISO 2813 and the ISO 7724 colorimetry series.
• The standard lists defects that should not be present (e.g., wrinkling, flaking, peeling, cracking, fish eyes, fingerprints, lack of hiding power).

Practical applications and who uses it

ISO 11347 is used to ensure consistent, contract‑defined exterior finish quality on large yachts. Typical users:

• Yacht builders and shipyards - to define acceptance criteria for final topcoats.
• Coating formulators and applicators - to verify that application processes meet visual appearance requirements.
• Quality control and inspection teams - to perform objective measurements and pass/fail assessments.
• Owners, brokers and ship surveyors - to specify expected finish levels in purchase or refit contracts.

Benefits:

• Establishes objective, repeatable measurement methods for gloss and colour.
• Provides a common language for acceptable surface defects and cosmetic quality during delivery inspections.

Related standards

• ISO 2813 - Determination of specular gloss of non‑metallic paint films (20°, 60°, 85°)
• ISO 7724-1/2/3 - Paints and varnishes - Colorimetry: principles, measurement and calculation of colour differences
• ISO 8666 - Yacht length (reference for LH definition)

Keywords: ISO 11347:2012, large yachts, visual appearance, coatings, gloss measurement, colour difference, orange peel, fairness, coating inspection, yacht finish quality.