ISO 25861:2007

Overview

ISO 25861:2007 specifies requirements for daylight signalling lamps used in marine navigation. The standard applies to lamps required under SOLAS Chapter V and the International Code of Safety for High‑Speed Craft (Chapter 8), and it implements the IMO Performance Standards for Daylight Signalling Lamps (MSC.95(72)). ISO 25861:2007 covers functional, photometric, ergonomic, environmental and type‑approval requirements to ensure reliable visual signalling between ship-to-ship and ship-to-shore by day and night.

Key topics and technical requirements

• Required function: Lamps must convey clear, distinguishable light signals both by day and night and indicate operational status.
• Luminous intensity & visibility: Minimum required luminous intensity is 60 000 cd (visibility ≥ 2 nautical miles at atmospheric transmission 0.8). Axial intensity must reach ≥ 90% of peak.
• Beam divergence & shape: Half‑peak divergence ≤ 9°, tenth‑peak divergence ≤ 14°. Effective emission sectors must be circular.
• Chromaticity: White signal chromaticity must fall inside specified CIE chromaticity corner coordinates (x,y): 0.525/0.382, 0.525/0.440, 0.452/0.440, 0.310/0.348, 0.310/0.283, 0.443/0.382.
• Switch times: Sum of switch‑on and switch‑off times shall not exceed 500 ms. Photometric testing requires high‑speed sampling (≥250 readings/s, integration ≤4 ms).
• Power & battery: Lamps must not rely solely on ship power; portable battery ≤ 7.5 kg, capacity ≥ 2 hours. Battery charge level indication required when separate power is used.
• Durability & safety: Minimum protection rating IP56, anti‑magnetic materials, controlled surface temperatures per IEC 60598‑1, resistance to condensation, and compliance with IEC 60945 durability and EMC requirements.
• Maintenance & spares: At least three spare illuminants of type‑tested design must be supplied. Lamps must be serviceable in darkness and operable with heavy gloves.
• Mounting & ergonomics: Pedestal mounting rules (900 mm clear radius, sighting height 1.5 m, guardrail if platform >230 mm) and fixed sighting mechanism aligned with optical axis.
• Type approval tests: Photometric, chromaticity, switch time, environmental, battery capacity, temperature, shock and life‑duration tests are specified for certification.

Applications and users

ISO 25861:2007 is used by:

• Ship designers and naval architects specifying navigation equipment for compliance with SOLAS and high-speed‑craft rules.
• Equipment manufacturers and test labs for product design, type approval and certification.
• Flag administrations, surveyors and maritime safety authorities responsible for approval and inspection.
• Ship operators and procurement teams selecting compliant daylight signalling lamps for safety and communication.

Related standards

• IMO Res. MSC.95(72) - Performance standards for daylight signalling lamps
• ISO 17884 - Searchlights for high‑speed craft
• IEC 60529 (IP Code), IEC 60598‑1, IEC 60945
• IMO Res. A.694(17), A.813(19)

Keywords: ISO 25861:2007, daylight signalling lamps, marine navigation, SOLAS, luminous intensity, chromaticity, type approval, EMC, IP56.