EN ISO 25119-3:2023 PDF

Overview

EN ISO 25119-3:2023 - "Tractors and machinery for agriculture and forestry - Safety-related parts of control systems - Part 3: Series development, hardware and software" (adoption of ISO 25119-3:2018) provides general principles for the design and development of safety-related parts of control systems (SRP/CS) used on tractors, self-propelled ride-on machines and mounted, semi‑mounted and trailed agricultural and forestry machinery. Published by CEN, this standard focuses on series development activities for hardware and software of electrical/electronic/programmable electronic systems (E/E/PES) as they relate to mechatronic systems. It can also be applied to certain mobile municipal equipment (e.g. street‑sweeping machines).

Key topics and requirements

The document establishes high‑level, practical requirements (not specific AgPL/performance levels) for SRP/CS development, including:

• System design principles for SRP/CS: objectives, prerequisites, structuring safety requirements and the technical safety concept.
• Hardware requirements: lifecycle considerations, design for safety, and mitigation of E/E/PES malfunctions.
• Software requirements: development practices for safety-related software used in control functions.
• Interaction and integration: addressing hazards caused by malfunctioning behavior of interacting E/E/PES safety systems.
• Hazard scope: covers malfunctions that may cause secondary hazards (e.g. fire, insulation failure) when directly caused by E/E/PES faults.
• Examples covered: limiting current flow in electric hybrids to prevent insulation failure/shock, electromagnetic interference (EMI) affecting SRP/CS, SRP/CS designed to prevent fire.
• Exclusions: aircraft/air‑cushion agricultural vehicles, lawn and garden equipment, non‑E/E/PES systems (hydraulic, mechanical, pneumatic), and issues unrelated to E/E/PES malfunctions (nominal EMI, corrosion, friction‑induced insulation wear).
• Conformity guidance: supports presumption of conformity with relevant clauses of Machinery Directive (2006/42/EC) when used alongside companion parts of ISO 25119 (Parts 1, 2 and 4).

Applications and who uses it

EN ISO 25119-3:2023 is intended for:

• OEMs and manufacturers of tractors and agricultural/forestry machinery developing SRP/CS.
• Safety engineers and system architects defining technical safety concepts for E/E/PES.
• Software and hardware developers implementing safety-related control functions in series production.
• Compliance and certification bodies assessing machine safety against EU Machinery Directive requirements.
• Integration teams addressing EMI, hybrid-electric systems and interactions among safety systems.

Using this standard helps reduce risk from control-system malfunctions, improve system reliability, and demonstrate a structured approach to safety during series development.

Related standards

• EN ISO 25119-1:2023 (General principles)
• EN ISO 25119-2:2023 (Concept phase)
• EN ISO 25119-4:2023 (Production, operation, modification)
• ISO 12100 (General machine safety design principles)

Keywords: EN ISO 25119-3:2023, SRP/CS, tractors, agricultural machinery safety, E/E/PES, series development, hardware and software, CEN.