ISO 17339:2018

Overview

ISO 17339:2018 specifies design, performance and prototype testing requirements for sea anchors used with survival craft (lifeboats and liferafts) and rescue boats. Developed as a companion to IMO life‑saving appliance guidance, the standard ensures sea anchors perform reliably to stabilize craft, control drift and improve survivability in abandonment and rescue operations.

Key Topics and Requirements

• Performance criteria: Sea anchors must develop minimum drag forces by craft type and speed (see ISO 17339 for the full table). They must remain stable when towed up to 3 knot and unfold with the mouth open immediately on deployment.
• Towing line: Must be inherently rot‑proof, at least 30 m long and minimum 8 mm diameter. Required breaking loads include 7.5 kN for liferafts up to 10 persons and 10.0 kN for larger liferafts and other survival craft, or a safety factor of 3 based on towing strain at 3 knot.
• Materials and construction: Materials must be rot‑proof, corrosion‑resistant, oil and fungal resistant, and stable across stowage and operational temperature ranges (stowage −30 °C to +65 °C; seawater −1 °C to +30 °C). Attachments must retain form on deployment.
• Prototype testing: Defined tests include material tests (fabric and structural webbing strength), corrosion testing of metal parts (per ISO 9227), temperature cycling, deployment tests, towing tests (minimum 1 km at 2 and 3 knot), and ultimate strength tests.
• Environmental durability: Requirements include resistance to sunlight deterioration and specified accelerated weathering and immersion exposures as part of material qualification.

Applications and Practical Value

• Ensures consistent, evidence‑based design and testing of sea anchors so equipment performs in real emergency scenarios.
• Helps manufacturers demonstrate compliance for product certification and acceptance by maritime administrations and classification societies.
• Supports shipowners, lifeboat and liferaft manufacturers, rescue boat designers and safety equipment testers in selecting and verifying sea anchors suitable for specific craft capacities.
• Reduces risk during abandonment by standardizing deployment, towing and material performance expectations.

Who Should Use This Standard

• Marine safety equipment manufacturers and suppliers
• Lifeboat and liferaft designers and test labs
• Classification societies and maritime administrations
• Ship operators and procurement teams specifying survival equipment

Related Standards

• IMO International Life‑Saving Appliance (LSA) Code (implementation context)
• ISO 9227 (salt spray corrosion tests)
• ISO 4892‑2 (xenon‑arc accelerated weathering)
• ASTM D471 and EN 590 (fuel/immersion references)

Keywords: ISO 17339:2018, sea anchors, survival craft, liferaft, lifeboat, rescue boat, prototype testing, drag force, towing line, deployment test, maritime safety.