التحقيق في الحوادث وتحليل الأسباب الجذرية: دليل عملي لخبراء السلامة في جنوب إفريقيا

Why Incident Investigation Matters

Every workplace incident — from a minor near-miss to a fatal accident — holds valuable information that can prevent future occurrences. In South Africa, the OHSA (Act 85 of 1993) requires employers to investigate and report certain categories of incidents. But beyond legal compliance, effective incident investigation is the cornerstone of a proactive safety culture.

Legal Requirements Under the OHSA

Section 24: Reporting of Incidents

Section 24 of the OHSA requires employers to report certain incidents to the Department of Employment and Labour:

• Fatal incidents — must be reported immediately
• Incidents resulting in the person being unable to work for 14 or more days
• Major incidents as defined by specific regulations (e.g., structural failures, major fires, explosions)

General Administrative Regulations (GAR 8 & 9)

• GAR 8: Prescribes the form for reporting occupational injuries and diseases
• GAR 9: Requires employers to investigate all incidents and keep records

Penalties for Non-Reporting

Failure to report notifiable incidents is a criminal offence under Section 38 of the OHSA:

• Fines up to R100,000
• Imprisonment of up to 2 years
• Or both

The Investigation Process: Step by Step

Step 1: Immediate Response

When an incident occurs, priorities are:

1. Ensure the safety of all persons in the area
2. Provide first aid and medical assistance to injured persons
3. Secure the scene — prevent further harm and preserve evidence
4. Notify relevant parties — management, health and safety representatives, emergency services if needed
5. Preserve the scene — do not disturb evidence unless necessary for rescue operations

Step 2: Assemble the Investigation Team

An effective investigation team typically includes:

• A trained incident investigator (ideally with Incident Investigation Training)
• The Health and Safety Representative for the area
• A subject matter expert relevant to the type of work
• A worker representative (preferably from the affected team)
• The supervisor responsible for the area (as a resource, not to lead the investigation)

Step 3: Gather Evidence

Evidence comes in four main categories:

Physical evidence:

• Damaged equipment, tools, or materials
• Environmental conditions (lighting, ventilation, housekeeping)
• Safety devices and their condition
• PPE worn by the injured person

Documentary evidence:

• Risk assessments and method statements
• Training records
• Maintenance logs
• Previous inspection reports
• Standard operating procedures

Testimonial evidence:

• Witness statements (take these as soon as possible while memory is fresh)
• Statements from the injured person (when medically appropriate)
• Expert opinions

Photographic/video evidence:

• Photographs of the scene from multiple angles
• Video footage (CCTV if available)
• Measurements and sketches

Step 4: Analyse the Evidence — Root Cause Analysis

This is where most investigations fail. Too often, investigations stop at the immediate cause ("the worker slipped") without uncovering the root causes ("why was the floor wet? Why was there no warning sign? Why was there no anti-slip treatment?").

Root Cause Analysis Methods

The 5 Whys Technique

The simplest yet often most powerful technique. Keep asking "Why?" until you reach the root cause:

Example:

• Incident: Worker suffered a hand laceration
• Why 1: His hand came into contact with the unguarded blade
• Why 2: The machine guard had been removed
• Why 3: The guard was removed for maintenance and not replaced
• Why 4: There was no lock-out/tag-out procedure for maintenance
• Why 5: The company had not developed a lock-out/tag-out programme

Root cause: Absence of a lock-out/tag-out programme (systemic failure)

Fishbone (Ishikawa) Diagram

Organises potential causes into categories:

• People — training, competence, supervision, fatigue, complacency
• Process — procedures, method statements, permits to work
• Plant/Equipment — condition, maintenance, guarding, PPE
• Place/Environment — housekeeping, lighting, weather, layout
• Policy — management systems, rules, standards, risk assessments
• Procurement — materials quality, contractor management

SCAT (Systematic Cause Analysis Technique)

SCAT was developed by the International Loss Control Institute and is widely used in South African industry, particularly in mining. It categorises causes as:

• Immediate causes — substandard acts and substandard conditions
• Basic causes — personal factors and job factors
• System failures — inadequate management systems or standards

Bow-Tie Analysis

A visual method that maps:

• Hazard → Threats → Preventive controls → TOP EVENT → Recovery controls → Consequences

Particularly useful for high-risk activities in mining, construction, and petrochemical environments.

Step 5: Determine Corrective Actions

Effective corrective actions follow the Hierarchy of Controls:

1. Elimination — remove the hazard entirely
2. Substitution — replace with something less hazardous
3. Engineering controls — physical barriers, guarding, ventilation
4. Administrative controls — procedures, training, signage, scheduling
5. PPE — personal protective equipment (last resort)

SMART Corrective Actions

Every corrective action should be:

• Specific — clearly define what must be done
• Measurable — how will you verify completion?
• Assigned — who is responsible?
• Realistic — is it achievable with available resources?
• Time-bound — when must it be completed?

Step 6: Write the Investigation Report

A comprehensive investigation report should include:

1. Incident details — date, time, location, persons involved
2. Description of what happened — factual, chronological account
3. Injuries/damage — nature and extent
4. Evidence gathered — summary of all evidence categories
5. Analysis — root cause analysis findings
6. Contributing factors — all factors that contributed to the incident
7. Root causes — systemic failures identified
8. Corrective actions — with responsibilities and deadlines
9. Recommendations — broader organisational improvements
10. Appendices — photographs, witness statements, diagrams

Step 7: Follow Up

An investigation is only as good as the implementation of its corrective actions:

• Track corrective actions to completion
• Verify effectiveness through follow-up inspections
• Share lessons learned across the organisation
• Update risk assessments based on findings
• Review and revise procedures as necessary

Common Investigation Mistakes

1. Blaming the worker — focusing on human error without examining the system that allowed it
2. Stopping at the immediate cause — not asking "Why?" enough times
3. Delayed investigation — evidence deteriorates and memories fade
4. Untrained investigators — using persons without proper investigation methodology training
5. No follow-up — recommendations made but never implemented
6. Confirmation bias — looking for evidence that confirms a predetermined conclusion
7. Not involving workers — missing critical insights from those closest to the work

Building Investigation Competence

Effective incident investigation requires training. Key qualifications include:

• Incident Investigation Training — practical methodology for conducting investigations
• NEBOSH IGC — covers incident investigation principles within the broader safety management framework
• Root Cause Analysis Training — advanced techniques for complex incidents
• HIRA Training — understanding risk assessment methodology supports better investigation

How OHS Compliance Group Can Help

Our Incident Investigation Training course equips safety professionals with practical skills in:

• Scene management and evidence preservation
• Witness interview techniques
• Root cause analysis methods (5 Whys, Fishbone, SCAT)
• Report writing and recommendations
• Legal requirements under the OHSA

Combined with the NEBOSH IGC, our training provides a comprehensive foundation for managing workplace incidents professionally and effectively.