What is an Occupational Health and Safety Management System (OHSMS)?

An effective occupational health and safety management system is built on five interdependent elements that together form the Plan-Do-Check-Act (PDCA) cycle. Each element plays a critical role in ensuring the system functions as a cohesive whole rather than a set of isolated procedures.

The occupational health and safety policy is a formal statement from top management committing the organisation to providing safe and healthy working conditions, eliminating hazards, reducing risks, and continually improving the OHSMS. The policy sets the direction for all health and safety activities and must be communicated to all workers, made available to interested parties, and reviewed regularly to remain relevant.

Hazard identification is the process of recognising sources of potential harm in the workplace, including physical, chemical, biological, ergonomic, and psychosocial hazards. Under ISO 45001, hazard identification must be proactive and ongoing, covering routine and non-routine activities, emergency situations, and the activities of contractors and visitors. A thorough hazard identification process is the foundation on which the rest of the occupational health and safety management system is built.

Risk assessment involves evaluating the likelihood and potential severity of harm arising from identified hazards, taking into account existing controls. The output of this process is a prioritised risk profile that informs where the organisation needs to focus its control efforts. ISO 45001 requires risk assessments to be documented and reviewed whenever there are changes to operations, legal requirements, or the outcomes of incidents and audits.

Controls are the measures put in place to eliminate hazards or reduce risks to an acceptable level. ISO 45001 adopts the hierarchy of controls as the preferred approach, requiring organisations to work through the following sequence: elimination, substitution, engineering controls and reorganisation of work, administrative controls, and personal protective equipment (PPE). Higher-order controls such as elimination and substitution are always preferred over lower-order controls such as PPE, as they address the root cause rather than managing the exposure.

Monitoring and measurement verify that the OHSMS controls are performing as intended. This includes tracking leading indicators such as training completion rates and near-miss reporting, as well as lagging indicators such as incident and injury rates. Internal audits, legal compliance evaluations, and management reviews are also part of the monitoring element, providing the data needed to drive continual improvement across the system.

ISO 45001 places worker consultation and participation at the heart of the OHSMS. Organisations must consult workers on matters such as hazard identification, risk assessment, and incident investigation, and must remove barriers to participation such as language, literacy, or fear of reprisal. Where they exist, workers’ representatives must be involved. This requirement sets ISO 45001 apart from earlier standards and reflects the principle that the people exposed to hazards are best placed to identify them.

The benefits of occupational health and safety management systems extend across the whole organisation, from the shop floor to the boardroom:

• Reduced workplace injuries and ill health – A proactive, risk-based approach identifies and eliminates hazards before incidents occur, protecting workers and reducing the human and financial cost of workplace harm.
• Legal and regulatory compliance – A structured OHSMS helps organisations identify applicable health and safety legislation and maintain documented evidence of compliance, reducing the risk of enforcement action, fines, and prosecution.
• Lower operational costs – Fewer incidents means reduced absenteeism, lower insurance premiums, less disruption to operations, and reduced costs associated with investigation and remediation.
• Enhanced reputation and trust – ISO 45001 certification demonstrates a credible commitment to worker welfare, strengthening confidence among employees, clients, regulators, and the wider public.
• Improved employee engagement and morale – Workers who feel safe and valued are more productive, more engaged, and less likely to leave. A strong safety culture signals that the organisation genuinely cares about its people.
• Competitive advantage – ISO 45001 certification is increasingly a prerequisite for tendering in public sector contracts and large supply chains, opening doors to new market opportunities.
• Continual improvement – The PDCA cycle embedded in the OHSMS ensures health and safety performance improves over time, responding to changes in the business, its workforce, and its operating environment.
• Better risk management – A systematic approach to hazard identification and risk assessment reduces the likelihood of major incidents and strengthens the organisation’s overall resilience.