Maintenance safety

Why maintenance concentrates risks

Unlike production work, which is carried out with the machine in its safe configuration and with the guards installed, maintenance often requires accessing hazardous areas, removing guards, working on live components or components with stored energy (electrical, hydraulic, pneumatic, mechanical, thermal, chemical, or gravitational), and doing so under time pressure to restart production. Furthermore, the tasks are variable and non-repetitive, making standardized procedures difficult, and are sometimes performed unsupervised or by external contractors.

The most common accident mechanisms are the unexpected start-up of a machine during work, electrical contact, the release of stored energy, entrapment by moving parts, falls from heights while accessing equipment, fire or explosion during hot work , exposure to substances in pipes and tanks, and a lack of coordination between maintenance, production, and contractors. The EU-OSHA Safe Maintenance campaign summarized five basic rules: plan, make the work area safe, use appropriate equipment, work according to plan, and perform final checks.

Royal Decree 1215/1997 stipulates in its Annex II that maintenance, adjustment, unlocking, inspection or repair operations of work equipment that may pose a danger to the safety of workers shall be carried out after having stopped or disconnected the equipment, having verified the absence of dangerous residual energies and having taken the necessary measures to prevent its accidental start-up or connection while the operation is being carried out; when stopping is not possible, measures must be taken to ensure that the operations are carried out outside of dangerous areas.

Essential control measures

• Machine lockout. Formal procedure for separating all energy sources, locking with personal devices and padlocks, signaling, dissipating residual energy and verifying the absence of energy before intervening (NTP 1117).
• Special work authorizations. Work permits for high-risk interventions (hot work, confined spaces, electrical work, work at height), which define conditions, measures, responsible parties and validity period (NTP 562).
• Planning. Prior analysis of the task, specific risk assessment, work procedure, identification of energies, tools and PPE needed, and sufficient time without undue pressure.
• Manufacturer’s instructions. Perform maintenance according to the manual, using the access points and maintenance methods specified, without improvising methods or disabling safety devices.
• Trained and authorized personnel. Only workers trained on the equipment, the risks and the procedures, with express authorization and, where applicable, specific qualification ( electrical risk , confined spaces).
• Coordination with production and contractors. Communication of the intervention, delivery of the consigned equipment, coordination of business activities with external maintenance companies and access control.
• Safe replacement. Before returning the equipment to production, removal of tools and personnel, installation of guards, functional check and formal communication of the end of the intervention.
• Record keeping and learning. Recording of interventions, permits and incidents, and analysis of near misses to review procedures.

Maintenance and integration of prevention

• Design for maintenance. Choosing equipment that allows for safe intervention (access, lockout points, reduced-speed maintenance modes and sensitive controls) reduces the risk at the source.
• Preventive maintenance. Planned maintenance of equipment and facilities is both an obligation (Royal Decree 1215/1997 and Royal Decree 486/1997) and a preventive measure: it reduces urgent corrective interventions, which are the most dangerous.
• Periodic checks. Equipment whose safety depends on its installation conditions is subject to initial and periodic checks by competent personnel, with documented results.
• Installations subject to regulation. Elevators, electrical installations, pressure vessels, thermal installations and others require maintenance by authorized companies and regulatory inspections.
• Maintenance contracts. External companies must receive information about the center’s risks and measures, provide proof of training and equipment, and apply the owner’s lockout/tagout procedures and permits.
• Indicators. Urgent corrective interventions, permits issued, maintenance incidents, and deviations in energy-isolation audits allow performance to be monitored.

Organizational application: how to manage maintenance safety

1. Inventory the equipment and facilities with their power sources, energy-isolation points, manuals, and maintenance requirements.
2. Implement a lockout procedure with locking devices, padlocks and personal tags, verification of absence of energy and controlled de-lockout.
3. Define the work permit system for high-risk interventions, including those responsible for issuance, conditions, and closure.
4. Plan preventive maintenance and regular regulatory checks, reducing urgent corrective interventions.
5. Train and authorize in-house maintenance personnel and verify the training and procedures of contractors, integrating the coordination of business activities.
6. Establish communication with production for the delivery and replacement of equipment, with documented final checks.
7. Record interventions, permits and incidents and analyze them periodically to review procedures and training.

Preventive management software allows you to link equipment inventory with energy-isolation procedures, manage work permits with approval workflows, record checks, and maintain documentation for maintenance contracts.

Limits and common mistakes

1. Intervene with the machine running or without being locked out to avoid production stoppages.
2. Record only electrical energy, neglecting hydraulic, pneumatic, stored mechanical or gravitational energies.
3. Using shared locks or tags, or removing them without verifying that all personnel have left the area.
4. Denying work permits for high-risk interventions because they are considered routine.
5. Do not inform or coordinate with maintenance contractors about the risks and procedures of the center.
6. Return the equipment to production without installing guards or checking its operation.

The requirements applicable to work equipment, facilities and coordination with contractors are detailed in the cited regulations and in the INSST NTPs; this sheet is for informational purposes.

Regulatory and reference framework

• Royal Decree 1215/1997, of July 18. Use of work equipment; Annex II on maintenance, adjustment, repair and check operations.
• Royal Decree 486/1997, of April 14. Workplaces ; periodic maintenance of facilities and workplaces.
• Royal Decree 171/2004, of January 30. Coordination of business activities, applicable to maintenance contracts.
• NTP 1117: Machine Lockout (INSST) . Procedure for separation, lockout, dissipation and verification of energies.
• NTP 562: Preventive management system: authorizations for special work (INSST) . Work permits for high-risk interventions.
• Fact sheet 88: Safe Maintenance. Safe Workers (EU-OSHA) . Basic rules for safe maintenance in the European growing season.

Royal Decree 614/2001 regulates work on electrical installations and Royal Decree 1644/2008 requires that machines be designed to allow safe maintenance; industrial safety regulations set the maintenance and inspections of specific installations.