Overview
ISO 14120:2015 - Safety of machinery - Guards sets out general requirements for the design, construction and selection of fixed and movable guards used to protect people from mechanical hazards. Published in 2015 (second edition), it applies to guards fitted to machinery manufactured after publication. The standard focuses on guard performance, human factors, materials and verification, but does not cover interlocking devices (see ISO 14119) or special protective systems such as ROPS/FOPS/TOPS.
Key topics and technical requirements
- Scope and risk assessment: Integrates with a machine risk assessment (per ISO 12100) to determine guarding needs and selection.
- Design and construction: Requirements for guarding geometry, access control, avoidance of crushing/trapping points, durability, hygiene, cleaning and removal of fixed guards.
- Human and ergonomic aspects: Safety distances, control of access to hazard zones, viewing, ergonomic considerations and intended use.
- Materials and mechanical properties: Requirements for material selection, rigidity, impact and ejection resistance, corrosion and microorganism resistance, thermal stability, flame resistance and non‑toxicity.
- Movable guards and fastening: Criteria for movable and adjustable guards, secure fixing, retained fastenings and guidance on removal/reattachment.
- Containment and ancillary hazards: Guidance on containment of ejected parts, hazardous substances, noise, radiation and electrostatic issues.
- Verification and testing: Verification/validation methods, with informative annexes describing example mechanical tests (projectile and pendulum) and retained fastening examples.
- Information for use: Requirements for marking, warnings and documentation covering installation, operation, removal, inspection and maintenance.
Applications and users
ISO 14120 is intended for anyone involved in the lifecycle of machinery guarding:
- Machine designers and OEMs - to design compliant fixed and movable guards and specify materials and fastening methods.
- Safety engineers and risk assessors - to define appropriate guard types and safety distances during risk assessment.
- Manufacturers and integrators - to select, install and verify guards on production equipment.
- Maintenance and inspection personnel - to follow requirements for removal, inspection and retained fastenings.
- Test laboratories and compliance officers - to validate guard performance and prepare conformity documentation.
Common practical uses: specifying machine guarding in procurement, documenting guarding in machine manuals, verifying guard robustness for impact/ejection resistance, and aligning guard design with ergonomic and hygiene requirements.
Related standards
- ISO 12100 - Safety of machinery - general principles for risk assessment and risk reduction.
- ISO 14119 - Interlocking devices associated with guards (covers interlocks excluded from ISO 14120).
- ISO 13855 - Positioning of safeguards in relation to the approach speeds of parts of the human body.
Keywords: ISO 14120, safety of machinery, guards, fixed guards, movable guards, machine guarding, guard design, risk assessment, ISO 14119, ISO 12100.