Machine Risk Assessment
A machine risk assessment is a structured, documented process required under WorkSafeBC OHSR and CSA Z432/ANSI B11 to identify machine hazards, estimate and evaluate risk (likelihood × severity of harm), and define/verify safeguards so residual risk is acceptable. It involves hazard identification, risk estimation, control implementation, and ongoing review to ensure safe machine operation.
On a manufacturing shop floor, machine risk assessment is triggered when new machinery is installed, modified, or when work processes change. The workflow includes scoping the machine boundary and tasks, identifying mechanical, electrical, and ergonomic hazards using CSA Z432 checklists, estimating risk via a likelihood-severity matrix, and applying the hierarchy of controls (engineering, administrative, PPE). Workers must be involved, and assessments are documented and reviewed after incidents or regulatory changes. Integration with systems like SafeDesk includes machine registries, task-based risk records, and safeguard tracking.
- Treating machine guarding as a checklist item instead of a full risk assessment, neglecting design requirements per CSA Z432 and non-routine tasks like maintenance.
- Failing to involve workers and consider ergonomic/MSI factors, such as force, repetition, and posture, as required by BC OHSR Part 4.
- Conducting a one-time assessment with no structured review when conditions change, such as modifications, layout changes, or regulatory updates.
Which standards should a BC machine risk assessment explicitly reference to demonstrate due diligence?
A BC machine risk assessment should reference BC OHSR Part 12, CSA Z432, the WorkSafeBC Safeguarding Machinery and Equipment manual, and WorkSafeBC risk definitions. For imported equipment, ANSI B11.0/B11.19/B11.TR3 and ISO 31000 may also be relevant.
How should risk be quantified or rated in a machine risk assessment consistent with WorkSafeBC expectations?
WorkSafeBC does not mandate a single scoring method but emphasizes severity, duration/frequency of exposure, and likelihood. Common practice uses a risk matrix (e.g., 4x4 or 5x5) with severity levels (Minor to Catastrophic) and likelihood levels (Rare to Almost certain), classifying risk as Low/Medium/High/Intolerable.
How do machine risk assessments interface with lockout/tagout and energy isolation procedures?
Risk assessments must identify all energy sources and tasks where unexpected energization may occur. For such tasks, lockout or energy isolation is required. The assessment informs lockout procedure design, verification steps, and inspection frequency, with evidence of integration in documentation.