Overview
EN ISO 16231-2:2015 (ISO 16231-2:2015) - "Self‑propelled agricultural machinery - Assessment of stability - Part 2" defines standardized test procedures for determining static stability of ride‑on agricultural machines. The standard specifies methods to determine the centre of gravity (COG) for un‑laden and laden machines (including combinations with attachments) and procedures to calculate the static overturning angle (SOA). Requirements for operator protective structures and ROPS are covered in separate standards.
Key topics and technical requirements
- Centre of gravity determination
- Method for the un‑laden machine using scales and support stands (see Clause 4.1).
- Methods for laden machines and machines with attachments: graphical and mathematical approaches (Clause 4.3).
- Reference to ISO 789-6 for COG test procedures and ISO 16231-1 for principles.
- Static overturning angle (SOA)
- Procedures to determine lateral roll‑over and tip‑over angles (Clauses 5.1–5.6).
- Distinct treatment for machines with different axle/steering configurations: swivelling axles, fixed axles, tracked machines, individual wheel suspension, and axle locking or limiting devices.
- Tip forward and tip rearward calculations and impact of body levelling systems.
- Calculation and comparison
- Normative calculation methods (Annex C) for RSSA (defined in the standard) and worked examples in informative Annexes A and B.
- Discussion of dynamic effects on roll/tip risk (Annex D).
- Regulatory alignment
- Informative Annex ZA links the standard to EU Machinery Directive 2006/42/EC for conformity assessment.
Applications and who uses it
- Manufacturers and designers - validate machine stability, optimize component placement, and demonstrate compliance with stability requirements.
- Test laboratories and certification bodies - perform reproducible COG and SOA tests for type approval and conformity assessment.
- Safety engineers and risk assessors - integrate static stability data into machine risk assessments and safety specifications.
- Regulators and procurement teams - assess machine suitability for intended operating slopes and conditions.
Related standards
- ISO 16231-1 - Assessment of stability: Principles
- ISO 789-6 - Agricultural tractors: Centre of gravity test procedures
- EU Directive 2006/42/EC - Machinery safety (referenced via Annex ZA)
EN ISO 16231-2:2015 is essential for consistent, repeatable evaluation of static stability in self‑propelled agricultural machinery, supporting safer design, testing, and regulatory compliance.