1. Introduction: Essence of Compliance in Power Transmission
The operational reliability and safety of industrial facilities are directly linked to the integrity of mechanical power transmission systems. With the approaching period of enhanced enforcement and the full entry into force of the new Machinery Directive (now Regulation (EU) 2023/1230), which replaces Directive 2006/42/EC, from 2027, 2026 is a critical year for preparation. These developments highlight the importance of proactive compliance with safety standards, especially for existing machines undergoing modifications and new installations. The focus shifts to even more stringent risk assessment and the implementation of advanced safety measures to prevent accidents, minimize downtime and ensure operational efficiency.
Accidents involving mechanical power transmission systems, such as rotating shafts, gears, belts and chains, often lead to serious injuries and significant production losses. An incident can lead to hundreds of hours of unplanned downtime and costs of up to €5,000 to €20,000 per hour, depending on the production line. The implementation of the most recent NEN, EN and ISO standards is not an optional consideration, but an absolute condition for sustainable and safe business operations in the Benelux manufacturing industry.
2. Scope and Compliance
The tightened safety standards are widely applicable within the manufacturing industry in the Benelux. They concern any organization that designs, manufactures, installs, operates or maintains mechanical power transmission systems. This includes sectors such as chemical, food and beverage manufacturing, automotive, metal processing and logistics.
Specific equipment covered by these standards includes, but is not limited to:
- Drive systems: Electric motors, combustion engines, hydraulic and pneumatic actuators.
- Transmission elements: Gearboxes (straight, bevel, bevel, worm gears), couplings (elastic, rigid, fluid), belt drives (V-belts, toothed belts), chain drives (roller chains, plate chains) and axles.
- Auxiliary systems: Lubrication systems, braking systems, monitoring systems (vibration, temperature).
- Security systems: Guards, emergency stop devices, safety interlocks.
Compliance is mandatory for:
- Machine manufacturers: Responsible for designing and building machines that meet CE marking requirements.
- Installers and integrators: Responsible for the correct installation and integration of machines and components, including the conformity of the whole.
- Operators (end users): Responsible for safe operation, correct maintenance and keeping machines up to date in accordance with applicable regulations, especially during modifications or overhauls.
3. Key Requirements: Overview and Deadlines
The coming period requires a renewed commitment to the following core requirements, which will become even more important due to tightened enforcement from 2026 and the new Machinery Directive. The focus is on prevention by design, effective security and thorough documentation.
Table 1: Overview of Core Requirements and Relevant Standards
| Requirement | Relevant Standard(s) | Deadline Compliance | Description |
|---|---|---|---|
| Risk Assessment & Risk Reduction | NEN-EN-ISO 12100:2010 (Revision expected 2023) | Continuous, with reassessment in case of modification. Mandatory update for 2026. | Systematic identification of hazards, estimation and evaluation of risks, and application of risk reduction measures (inherent safe design, technical protection measures, additional measures). |
| Design Safety Control Systems | NEN-EN-ISO 13849-1:2015 (Revision 2023) | Fully compliant with the new revision from 2026. | Design and verification of safety-related parts of control systems, including Performance Level (PL) calculations for components such as emergency stops and interlocks. A minimum of PLc or PLd is often required. |
| Emergency stop facilities | NEN-EN-ISO 13850:2015 | Continuously, with checks during inspections. | Placement, design and functionality of emergency stop devices to quickly and safely stop dangerous movements. Controls must be red on a yellow background. |
| Safety Distances & Fencing | NEN-EN-ISO 13857:2008 | Continuously, with checks during inspections. | Determination of safe distances to hazardous zones and requirements for the design of fixed and movable guards. An opening of 8 mm can already be dangerous. |
| Electrical Equipment of Machines | NEN-EN-IEC 60204-1:2018 | Continuously, with checks during inspections. | Requirements for the electrical equipment of machines, including wiring, switchgear, motor protection and emergency stop circuits. |
| Ex-Protection (if applicable) | Directive 2014/34/EU (ATEX) | Ongoing, with periodic reassessment. | Requirements for equipment and protective systems intended for use in potentially explosive atmospheres. This includes ATEX certification for motors, sensors and other electrical components in zones 0, 1, 2, 20, 21, 22. |
| Documentation | Machinery Directive 2006/42/EC / Regulation (EU) 2023/1230 | From 2027, fully compliant with Regulation (EU) 2023/1230. | Technical files, operating manuals, maintenance instructions, declarations of conformity and risk assessments must be current and available. |
4. Impact on MRO Operations
The tightened safety guidelines have a direct and significant impact on the Maintenance, Repair, and Operations (MRO) processes within your organization.
Maintenance strategies
- Predictive Maintenance: Implementation of condition monitoring systems becomes essential. This includes vibration analysis (in accordance with NEN-ISO 10816), temperature monitoring (e.g. bearing temperatures between 20°C and 70°C, with alarm at 85°C), oil analysis and acoustic monitoring. These systems detect wear or defects early, preventing unplanned downtime and increasing the lifespan of critical components by 15-25%.
- Planned Preventive Maintenance: Extensive inspection protocols for safety-related components. This includes regular checking of guards, emergency stops, safety door switches and the integrity of couplings and drive belts.
- Training & Competencies: Personnel must be periodically trained in the latest safety procedures and the use of advanced safety systems. This also includes the specific risks of mechanical power transmission and proper lockout/tagout (LOTO) procedures.
Purchasing & Logistics
- Certified Components: The purchasing department must give priority to spare parts and components that comply with the applicable standards and have the required certifications (CE, TUV, ATEX). Use of non-certified parts may result in non-compliance and void any warranties or liability coverage.
- Supplier selection: A thorough evaluation of suppliers is necessary. They must be demonstrably able to supply compliant and traceable products. UNITEC-D GmbH offers a comprehensive range of certified industrial spare parts, directly accessible via our E-Catalog.
- Inventory management: Maintain sufficient inventory of critical, certified safety components to enable rapid replacement and minimize downtime.
Documentation & Archiving
- Current Technical Files: All relevant documentation, including risk assessments, declarations of conformity, maintenance logs, schedules and manuals, must be up to date and easily accessible. The new Machinery Directive places higher demands on the digital availability and updating of these files.
- Change management: Any modification to a machine, no matter how minor, must be documented, including a reassessment of the risks and impact on safety functions. This is crucial for maintaining the CE marking.
5. Component Requirements: Certifications and Specifications
The selection of spare parts and components is critical for maintaining the safety compliance of power transmission systems. Not only the functionality, but also the certification and technical specifications are decisive.
General Requirements
- CE Marking: All components that fall under a European directive must have a CE marking. This confirms that the product meets the essential health and safety requirements.
- ATEX Certification: For applications in potentially explosive atmospheres (according to Directive 2014/34/EU), components such as motors, sensors, switches and brakes must be ATEX certified for the specific zone (e.g. Ex II 2G Ex db IIC T4 Gb for zone 1).
- TUV Certification: Many components, especially safety-relevant ones, carry a TUV quality mark, which indicates independent verification of product safety and quality.
Specific Components
- Bearing units: Roller bearings and plain bearings must meet the relevant ISO standards for dimensions (e.g. ISO 15), tolerances (e.g. ISO 286 for fits, such as shaft fit H7 and housing fit H7) and material strength. The service life (L10) of bearings must be calculated based on operating load and conditions, often resulting in a minimum MTBF of 20,000 hours for critical applications.
- Seals: Dynamic seals (oil seals) and static seals (O-rings) must withstand the operating temperature (e.g. -20°C to +120°C for NBR), pressure (up to 10 bar for rotary seals) and chemicals of the media. They are essential for preventing leaks and maintaining lubrication.
- Couplings: Must be designed to achieve torque transmission and accommodate any misalignment (radial up to 0.5 mm, axial up to 1.5 mm, angular up to 1°) without undue stress on the shaft and bearings. Safety couplings must meet the requirements for overload protection.
- Gears and Shafts: Must be constructed from materials of appropriate hardness and fatigue strength (e.g. hardened steel 42CrMo4, 58 HRC) and meet tolerances for concentricity and squareness (e.g. <0.02 mm deviation over 100 mm length) in accordance with ISO 1101.
- Motors & Gearboxes: Electric motors must meet efficiency classes (IE3, IE4) and insulation classes (e.g. F, 155°C) in accordance with NEN-EN-IEC 60034. Gearboxes must meet the power and torque requirements with an adequate service factor.
- Sensors & Actuators: Safety sensors (e.g. position, speed, temperature sensors) must have a Performance Level (PL) or Safety Integrity Level (SIL) that corresponds to the risk assessment of the machine.
6. Compliance Checklist for Maintenance Managers
This checklist provides a practical tool for maintenance managers and safety officers to assess and ensure compliance with the enhanced guidelines.
- Is there a current and validated risk assessment for each power transmission system, in accordance with NEN-EN-ISO 12100?
- Are all protective shields present, intact and correctly mounted, taking into account NEN-EN-ISO 13857?
- Are the emergency stop facilities easily accessible, functional and do they comply with NEN-EN-ISO 13850?
- Do the safety control systems meet the required Performance Level (PL) in accordance with NEN-EN-ISO 13849-1?
- Are all safety-related components (sensors, switches) periodically tested for correct operation?
- Is there a LOTO (Lockout/Tagout) procedure in place and is it strictly adhered to for all maintenance activities?
- Are all spare parts purchased with the required CE, TUV and/or ATEX certification?
- Are all electrical components of power transmission systems in accordance with NEN-EN-IEC 60204-1?
- Are vibration measurements (NEN-ISO 10816) and temperature monitoring performed consistently on critical bearings and gearboxes?
- Are maintenance personnel adequately trained in the latest safety procedures and use of PPE?
- Is the machine documentation (manuals, diagrams, declarations of conformity) up to date and accessible?
- Are changes to machines, including replacement of parts, documented and followed by a reassessment of the risks?
- Are there procedures for reporting and investigating near misses and accidents?
- Are internal audits carried out to verify compliance with safety procedures?
- Is there an up-to-date overview of all power transmission systems with their specifications and maintenance history?
- Is the lubrication of power transmission components (oil, grease) regularly checked and replenished/replaced according to specifications (e.g. viscosity at 40°C, pressure of 2-5 bar in lubrication systems)?
- Have measures been taken to prevent static electricity in potentially explosive atmospheres (ATEX zones)?
- Are the fits and tolerances checked when mounting shafts and bearings (e.g. with gauges or dial indicators accurate to 0.005 mm)?
- Are the tension bolts of critical components (e.g. motors, gear units) correctly tightened to the prescribed torque?
- Is the full entry into force of the new Machinery Directive Regulation (EU) 2023/1230 anticipated from 2027?
7. Common Non-Compliance Issues
Certain non-conformities relating to mechanical power transmission systems regularly come to light during audits and inspections. These problems not only lead to fines, but also increase the risk of serious accidents.
- Outdated or Missing Risk Assessments: Many organizations still work with initial risk assessments that have not been updated after modifications or changes to the production processes.
- Inadequate Guards: Inadequate or damaged guards, or guards that are easily removed without tools. Sometimes guards are deliberately removed for this purpose
