When a workplace injury, illness, incident or exposure occurs, employers face immediate questions: Who needs help? Must the regulator be notified? What evidence should be preserved? Who will investigate?
A clear response protects people, supports compliance and helps prevent recurrence. This practical overview explains employer responsibilities and what to expect from Alberta Occupational Health and Safety (OHS), the provincial government’s workplace health and safety regulator. It focuses on provincially regulated workplaces, with legal duties distinguished from recommended practices.
Immediate Response and Reporting
Start with care and control: arrange emergency assistance, protect others from danger, and notify the appropriate people within your organization.
Legal requirement: For Alberta work sites, the prime contractor—or the employer when there is no prime contractor - must notify OHS as soon as possible of specified serious events. These include:
- A worker fatality.
- An injury, illness or incident where there is reason to believe a worker has been or will be admitted to hospital beyond emergency-room or urgent-care treatment.
- An unplanned or uncontrolled explosion, fire or flood causing, or potentially causing, serious injury or illness.
- A crane, derrick or hoist collapse or upset.
- Failure or collapse of a building or structural component necessary for structural integrity.
Call the OHS Contact Centre at 1-866-415-8690. Do not wait for the investigation to finish. For these events, preserve the scene and related equipment and records. Exceptions allow attending to people, preventing further harm, protecting endangered property, or acting under authorized direction. [1]
Separate reporting requirements apply to specified mine incidents and radiation overexposures. An exposure does not automatically fall into the serious-event category; assess the applicable requirements and resulting harm. [7] [3]
What if nobody was seriously injured?
A potentially serious incident (PSI) meets two conditions: it was likely to cause serious injury or illness, and there is reasonable cause to believe corrective action may be needed to prevent recurrence. Investigate and submit the completed report through Alberta’s online service. A PSI alone does not require securing the scene, although preserving relevant evidence remains good practice. [2]
Employer Investigation Responsibilities
Legal requirement: For events covered by section 33, the responsible prime contractor or employer must investigate, prepare a written report describing the circumstances and corrective action taken, and retain it for at least two years after the event. The report must be readily available to an OHS officer on demand and provided to a Director. Share it with the joint health and safety committee or representative, where one exists; otherwise, make it available to workers once the investigation is complete. [3]
Alberta’s guidance also calls for involving the committee or representative in the investigation. [1]
Good practice: Appoint a capable investigation lead, define responsibilities, and bring in people with knowledge of the work. Obtain specialist help where technical questions exceed the team’s expertise. [6]
Less severe incidents and near misses still provide opportunities to identify hazards and improve controls, even when they do not meet the section 33 reporting threshold. [8]
Conducting a Useful Investigation
A useful investigation explains both what happened and why. CCOHS recommends examining underlying causes rather than stopping at an observation such as “worker error.” [4]
Good practice: Build a timeline and gather evidence promptly, subject to scene restrictions. Preserve photographs, video, equipment details, training records, procedures, maintenance records and relevant hazard assessments.
Interview witnesses individually, as soon as reasonably possible. Use open questions: “What did you see?” “What happened next?” Avoid leading answers, and distinguish direct observations from assumptions.
Examine the task, equipment, environment, supervision and work organization. For an illness or exposure, establish the substance or agent, exposure circumstances and duration, and controls in place. Seek qualified technical input where needed.
Record gaps and uncertainty honestly. Connect each conclusion to supporting evidence, then recommend specific measures that address the contributing factors. [4]
For example, if a worker slips near a leaking machine, “remind employees to be careful” leaves the source unresolved. A stronger response considers repairing the leak, controlling access, improving detection and checking similar equipment.
What to Expect From Alberta OHS
The employer’s investigation and the regulator’s investigation serve related purposes, but are separate processes. OHS involvement does not remove the employer’s investigation obligations. [3]
Alberta describes a process in which serious-incident calls are triaged and assigned to an investigator. OHS examines the causes and circumstances, gathers information, and assesses possible non-compliance. An enforcement review may result in referral to Alberta Justice for consideration of prosecution; charges are not an automatic outcome. [5]
Under the Act, officers can examine work sites, interview people, require records—including electronic records—and take samples or seize relevant items. They may also issue compliance, stop-work or stop-use orders where the statutory conditions are met. [3]
Good practice: Designate a contact to coordinate requests. Keep original evidence intact, record what was requested and supplied, and organize relevant procedures, training, maintenance and investigation records. Respond accurately, identify information still being verified, and track directions and deadlines.
OHS reporting, workers’ compensation reporting and internal incident reporting should each be checked separately. Completing one process should not be assumed to complete the others.
Closing the Loop With Corrective Action
A completed report is one milestone. Prevention depends on implementing the findings and checking whether the changes work. CCOHS recommends a corrective-action plan, implementation, evaluation and communication with workers, supervisors and management. [6]
Good practice: Give every action an owner, a target date and a way to confirm effectiveness. Record interim controls where the permanent solution will take time. Review whether the same hazard exists elsewhere.
Before closing the investigation, check:
- Required notifications and report submissions are complete.
- Evidence, findings and corrective actions are documented.
- Required recipients have received the report.
- Actions have owners, dates and completion records.
- Follow-up confirms controls are effective.
atworkCare’s structured investigation workflow supports evidence documentation, contributing-factor analysis, findings and corrective-action management. Connected with incident reporting and follow-up, it helps teams maintain a clearer investigation record and see what remains outstanding.
The value of an investigation lies in the safer workplace it helps create.
Information reviewed October 2, 2026. This overview covers the general incident-investigation framework; specialized hazards and activities may carry additional requirements. Consult the applicable legislation and current Alberta OHS guidance for your circumstances.