ISO 5480:2020

Overview

ISO 5480:2020 - Ships and marine technology - Guardrails for cargo ships - specifies the dimensions, materials, manufacture and finish requirements for guardrails and stanchions fitted on exposed freeboard and superstructure decks of cargo ships. Its purpose is to reduce the risk of personnel falling overboard or to lower decks. The standard applies to cargo ships (excluding guardrails fitted near compasses) and aligns cargo-ship design with the International Convention on Loadlines (Annex 1, Ch. II, Reg. 25).

Key topics and technical requirements

• Principal dimensions
  • Toprail height: minimum 1 000 mm measured from toprail to deck/waterway plank.
  • Opening below lowest rail: max 230 mm.
  • Opening between upper courses: max 380 mm.
  • Maximum stanchion spacing: 1 500 mm.
• Materials
  • Stanchions and stays: weldable steel (stanchion flat bar 60 × 15 mm or equivalent section modulus; stays 60 × 9 mm or equivalent).
  • Steel toprails: tube min 34 mm OD, wall ≥ 2.6 mm, or wooden toprails 125 × 60 mm (teak or equivalent hardwood).
  • Lower rails: solid round bar ≥ 19 mm or tube 26.9 mm OD, wall ≥ 2.3 mm.
  • Fasteners and finishes: conform to ISO 65, ISO 887, ISO 898-1 and galvanizing per ISO 1461.
• Design & installation
  • Rails welded to inside edge of stanchions or passed through holes and welded.
  • Stays welded to stanchions at mid‑height at approximately 30°.
  • Fairlead and special arrangements illustrated; stays may be omitted where calculations permit.
• Structural calculation
  • Annex A provides a method for summation of section modulus for combined stanchion + stay, allowing optimized sizing when appropriate.
• Quality & finish
  • Components must be free from defects likely to cause injury and receive protective finishes suitable for shipboard environment.

Applications and users

ISO 5480:2020 is used by:

• Shipbuilders, shipyards and manufacturers for guardrail design and fabrication.
• Naval architects and marine engineers specifying deck safety features.
• Classification societies and flag state surveyors assessing compliance with loadline and safety requirements.
• Ship owners and operators for procurement, retrofit and maintenance specifications.
• Safety and offshore personnel implementing fall-prevention measures on cargo ships.

Practical applications include design drawings, production tolerances, on-board inspections, and specification of materials, welding and protective coatings.

Related standards

• IMO International Convention on Load Lines, 1966 (referred to in the Introduction)
• ISO 1461 - Hot‑dip galvanizing
• ISO 80000-4 - Quantities and units: mechanics (section modulus reference)
• ISO 65, ISO 887, ISO 898-1 - referenced for tubes and fasteners

Keywords: ISO 5480:2020, guardrails, cargo ships, stanchions, toprails, marine safety, ship design, guardrail dimensions, shipboard fall prevention.