ISO 3796:2023

Overview

ISO 3796:2023 - Ships and marine technology - Clear openings for external single-leaf doors specifies standardized clear opening dimensions (nominal sizes) for all types of external single-leaf doors on board ships where coamings are required. This third edition updates the 1999 version and provides guidance on frame types, corner radii and preferred geometries to reduce structural stress and cracking.

Key topics and requirements

• Scope: Defines nominal clear opening dimensions for external single-leaf shipboard doors intended to fit within coamings.
• Clear opening definition: Clear light dimensions are given as height (L) and width (B) measured inside the door frame.
• Frame types: Covers typical frame designs - angle bar frames (rounded or square corners) and flat bar frames (rounded corners).
• Corner radius (R): Corners can be square or rounded; rounded corners with R = 100 mm are preferred to prevent cracking. For plates subject to high longitudinal bending loads, openings should be calculated and doors with rounded corners used.
• Nominal sizes: Table of nominal sizes provided in millimetres. Representative sizes range from 1 200 × 600 mm up to 1 800 × 900 mm (examples include 1 200×600, 1 400×750, 1 600×900, etc.). These sizes are used as the standard nominal dimensions for design and procurement.
• Editorial notes: There are no normative references; terms and definitions are provided for clarity. The third edition adds an angle bar frame with rounded 100 mm corners and introduces six additional nominal sizes.

Applications

• Ship designers and naval architects use ISO 3796:2023 when laying out accommodation, service and machinery spaces to ensure standardized door openings and compatibility with coamings.
• Shipyards and fabricators reference the standard for production, cutting and reinforcement around door openings to meet nominal sizes and recommended corner radii.
• Door manufacturers and suppliers use the nominal sizes for product ranges and to specify frames that fit standardized coamings.
• Classification societies, marine engineers and procurement teams rely on the standard for regulatory compliance, specification writing and minimizing retrofitting issues.

Related standards and sources

• Prepared by ISO/TC 8 (Ships and marine technology). For broader compliance, consult relevant classification society rules and other ISO standards on ship design and safety.
• For official text, figures and full nominal-size tables, obtain ISO 3796:2023 from ISO (www.iso.org).

Keywords: ISO 3796:2023, clear openings, external single-leaf doors, ships, nominal sizes, door frame, coamings, corner radius, ship design standard.