Applying the Hierarchy of Controls in ISO 45001 Operational Planning

Background, Operational Scope, and Affected Roles

ISO 45001 establishes an operational framework requiring organisations to eliminate hazards and reduce occupational health and safety risks. Traditional safety management frequently relies heavily on administrative rules and personal protective equipment to manage workplace exposures. Consequently, Clause 8.1.2 mandates that organisations must establish, implement, and maintain processes for hazard elimination and risk reduction using a defined hierarchy of controls. Quality managers, compliance leads, and internal auditors must evaluate operational planning to confirm that higher-level systemic controls are prioritised.

This operational scope affects top management, engineering teams, procurement specialists, line supervisors, and non-managerial workers. Relying exclusively on personal protective equipment leaves workers exposed to systemic workplace hazards if protective gear fails, is fitted incorrectly, or is neglected. ISO 45001 addresses this vulnerability by embedding the hierarchy of controls into general operational planning under Clause 8.1.1 and planning action under Clause 6.1.4. Internal auditors must verify that control measures systematically address risks at their source rather than delegating safety responsibility to individual workers.

Technical Nuances: The Five Levels of Operational Control

Clause 8.1.2 details five distinct control levels arranged in order of decreasing effectiveness. Under Clause 8.1.2 a), organisations must first seek to eliminate the hazard by removing the source of harm entirely. Under Clause 8.1.2 b), organisations must substitute hazardous processes, operations, materials, or equipment with less hazardous alternatives. Furthermore, Annex A.8.1.2 notes that organisations must consider combining multiple controls to reduce risks to levels as low as reasonably practicable.

Under Clause 8.1.2 c), organisations must implement engineering controls and reorganisation of work. Engineering controls isolate workers from hazards through collective protective measures such as ventilation systems, machine guarding, or guard rails. Reorganisation of work addresses systemic risk factors by adjusting work patterns, avoiding unhealthy work hours, or alleviating excessive workloads. Non-managerial workers must participate in determining actions to eliminate hazards under Clause 5.4 e) 3) and selecting control measures under Clause 5.4 e) 6).

Under Clause 8.1.2 d) and Clause 8.1.2 e), administrative controls and personal protective equipment form the final tiers of the control hierarchy. Administrative controls include periodic safety inspections, driver licensing, shift rotation, and training to prevent bullying or harassment. Personal protective equipment represents the least effective control tier and must be provided at no cost to workers where required by legal requirements. Organisations may use personal protective equipment as a temporary measure while higher-level engineering controls are being designed or implemented.

Audit Evidence and Verification Methods

Internal auditors must gather multi-faceted evidence to evaluate whether operational planning effectively applies Clause 8.1.2. Reviewing risk assessment documented information under Clause 6.1.2.2 reveals whether risk assessors default to personal protective equipment without evaluating higher-tier controls. Auditors must inspect capital expenditure plans, engineering specifications, and work procedure revisions to confirm that hazard elimination and engineering controls were evaluated during planning. Furthermore, auditors must verify that procurement processes under Clause 8.1.4.1 incorporate health and safety criteria before equipment or materials are introduced.

Auditors must also evaluate how organisations address systemic human factors and work organisation hazards identified under Clause 6.1.2.1 a). Interviewing non-managerial workers across operational areas verifies whether administrative controls and personal protective equipment are practical and properly maintained. Under Clause 10.2 d), when incidents or nonconformities occur, organisations must determine corrective actions in accordance with the hierarchy of controls. Auditors must cross-reference incident investigation corrective action logs to ensure recurring hazards are mitigated through systemic engineering or elimination measures.

What to do now

• Review risk assessment procedures to ensure risk control selection systematically follows the five-tier hierarchy of controls under Clause 8.1.2.
• Inspect current operational risk registers to verify that high-level risks rely on engineering controls or elimination rather than administrative rules alone.
• Audit procurement processes to confirm that health and safety criteria evaluate substitution options before hazardous materials or equipment are purchased.
• Sample incident investigation files under Clause 10.2 to verify that corrective actions implement systemic controls higher in the hierarchy.
• Conduct interviews with non-managerial workers to confirm their participation in determining control measures and assessing personal protective equipment adequacy.

Reference documents

• BS ISO 45001:2018 Occupational health and safety management systems — Requirements with guidance for use