Overview
ISO/TS 28923:2012 is an international technical specification developed by the International Organization for Standardization (ISO) that addresses the safety requirements for guards on moving parts of power transmission in agricultural machinery. Specifically, it focuses on fixed guards that require a tool for opening and interlocking movable guards used on self-propelled ride-on machines as well as mounted, semi-mounted, or trailed agricultural machines.
The document provides guidelines on the design, construction, and verification of these guards to minimize risks associated with power transmission components such as crushing, shearing, entanglement, or drawing-in hazards. Additionally, it specifies the type of safety information manufacturers must supply to operators, including warnings and safe working practices.
Key Topics
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Scope and Applicability
ISO/TS 28923:2012 covers guards on power transmission moving parts excluding:
- Agricultural and forestry tractors
- Aircraft and air cushion vehicles used in agriculture
- Lawn and garden equipment
- PTO drive shafts between tractors and implements
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Guard Types
- Fixed Guards: Must be opened only with tools to ensure intentional access.
- Interlocking Movable Guards: Equipped with devices that prevent operation when open and disengage power transmission.
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Design Requirements
- Guards must prevent access to hazardous areas during normal operation and service.
- Openings in guards (mesh, grille) must comply with safety distances specified by ISO 13857:2008.
- Guard strength must meet ISO 4254-1 requirements.
- Fixed guards should be attached securely, using permanent or tool-required fasteners or hinges with locking mechanisms.
- Interlocking guards must remain attached when open and require intentional action for adjustment.
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Safety Features
- Safety signs on guards indicating rotating parts.
- Audible or visible indicators when power supply is disengaged but parts are still moving.
- Locking devices to prevent guard opening until hazardous movements stop.
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Verification and Testing
Verification is done through inspections and testing during normal operation and service, ensuring compliance with safety requirements.
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Information for Use
Operators’ manuals must inform about residual risks and safe practices. Clear safety signs should be provided on guards or access points.
Applications
ISO/TS 28923:2012 serves a critical role in enhancing safety within the agricultural machinery sector by:
- Ensuring effective protection against injuries caused by moving parts of power transmission.
- Guiding manufacturers in the implementation of guards that balance safety and machine accessibility.
- Reducing downtime and accidents related to improper guarding or inadvertent access.
- Supporting compliance with international safety regulations to facilitate global trade.
- Assisting agricultural equipment designers, manufacturers, and safety inspectors in performing risk assessments and implementing appropriate safeguards.
This standard is particularly valuable for manufacturers of self-propelled, mounted, semi-mounted, or trailed agricultural machinery, who must incorporate tool-operated or interlocking guards on power transmission components to mitigate significant mechanical hazards.
Related Standards
ISO/TS 28923:2012 should be used in conjunction with the following relevant international standards for comprehensive machinery safety:
- ISO 12100:2010 - Safety of machinery - General principles for design, risk assessment, and risk reduction.
- ISO 4254-1 - Agricultural machinery - Safety - Part 1: General requirements.
- ISO 13857:2008 - Safety of machinery - Safety distances to prevent reaching hazardous areas by limbs.
These standards together provide a holistic framework for designing, building, and maintaining safe agricultural machinery, focusing on both hazards and risk management.
Keywords: ISO/TS 28923:2012, agricultural machinery safety, power transmission guards, fixed guards, interlocking movable guards, machine safeguarding, agricultural equipment safety, ISO agricultural machinery standards, machinery risk reduction, operator safety, moving parts hazard
Open preview (PDF)Agricultural machinery — Guards for moving parts of power transmission — Guard opening with tool
