Overview
EN ISO 3457:2008 (ISO 3457:2003 adopted by CEN) specifies definitions, performance requirements and characteristics for guards on earth‑moving machinery. The standard covers protective measures against mechanical, fluid and thermal hazards that can occur during normal operation and routine maintenance of machines defined in ISO 6165. It supports conformity with EU machinery directives (including 98/37/EC and 2006/42/EC) by offering presumption of conformity for relevant essential requirements.
Key topics and technical requirements
- Scope and terms: Defines principal terms such as guard, barrier guard, fender, fan guard, thermal guard, hose guard and distance guarding.
- Safety principles: Hierarchy of protection - eliminate hazards by design, guard where elimination is not feasible, warn where neither is possible.
- Guard design and attachment:
- Guards must be securely attached and use common fasteners or equivalent means.
- Access doors/guards required for routine maintenance must be easy to open/close, remain attached (hinge or tether), include means to keep closed (or open when required), and if removable parts exceed 20 kg they must have handholds or lift points.
- Guards must be free of sharp edges and projections (see ISO 12508).
- Strength and rigidity: Except for hose guards, each guard must resist deflection and permanent deformation under loads applied via a 125 mm diameter disc:
- 250 N if a person can touch the guard,
- 500 N if a person can fall or lean on it,
- 2000 N if the guard serves as a step/platform (see ISO 2867).
- Types of guarding covered: barrier guards, fenders, fan guards, thermal guards, hose guards, and distance guarding (relationship between guard openings and safety distances based on anthropometry).
- Maintenance context: Focus on hazards arising during routine maintenance tasks (lubrication, refueling, inspection, cleaning, adjustments).
Practical applications and users
- Intended for manufacturers, designers and safety engineers of construction and earth‑moving equipment (bulldozers, loaders, excavators, motor graders).
- Useful to procurement teams, compliance officers and test labs verifying machine guarding, and to fleet maintenance managers implementing safe maintenance procedures.
- Helps demonstrate conformity with EU machinery directives and supports risk reduction during machine operation and daily maintenance.
Related standards
- ISO 6165 - Basic types / vocabulary (earth‑moving machinery)
- ISO 2867 - Access systems
- ISO 3411 - Human physical dimensions / operator space envelope
- ISO 6682 - Zones of comfort and reach for controls
- ISO 9244 - Safety signs and hazard pictorials
- ISO 12508 - Bluntness of edges
EN ISO 3457:2008 is a practical reference for embedding robust machine guarding into earth‑moving equipment design and maintenance practices to reduce mechanical, fluid and thermal risks.
