Reporting Workplace Incidents in Ontario: Employer Requirements

Ontario Workplace Incident Reporting (OHSA section 51) Requirements

Learn which workplace incidents Ontario employers must report, including critical injuries, OHSA deadlines, WSIB reporting rules, near misses and O. Reg. 420/21 requirements. 

 

Ontario employers may have several reporting duties after a workplace incident. The correct response depends on what happened, how seriously someone was injured, whether medical attention was required, whether the worker could continue their usual work, and whether the event meets a separate reporting requirement under Ontario law.

 

The main legal requirements come from Part VII of the Occupational Health and Safety Act (OHSA), particularly sections 51 to 53.1, together with Ontario Regulation 420/21: Notices and Reports Under Sections 51 to 53.1 of the Act. WSIB has a separate injury and illness reporting system that may apply to the same incident.

 

This means one workplace event can create more than one obligation.

 

An employer may need to:

• make an immediate notification to the Ministry of Labour, Immigration, Training and Skills Development;
• provide written notice to the joint health and safety committee, health and safety representative or union;
• file a written Ministry report within a prescribed deadline;
• report the injury or illness separately to WSIB; and
• document and investigate the incident internally.

 

The first step is identifying which reporting trigger applies.

 

 

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What Workplace Incidents Must Be Reported in Ontario?

Ontario workplace reporting can be understood as three connected systems:

1. Internal workplace reporting
2. OHSA reporting to designated workplace parties and, in some situations, the Ministry
3. WSIB injury and illness reporting

These systems overlap, but they serve different purposes.

Internal Workplace Incident Reporting

Employers should have an internal procedure for workers to report workplace injuries, illnesses, hazards and near misses.

Internal reporting allows the employer to identify hazards, preserve information and determine whether a statutory reporting requirement has been triggered.

An incident that does not need to be reported externally may still deserve an internal investigation.

For example, a forklift that narrowly misses a pedestrian may not automatically create an OHSA notice or WSIB claim. It can still reveal a serious traffic-management hazard that should be addressed before someone is injured.

Internal reporting procedures should therefore make it easy for workers and supervisors to document events promptly and escalate serious incidents.

Incidents Reportable Under the OHSA

Part VII of the OHSA sets specific notification and reporting requirements for incidents including:

• workplace fatalities;
• critical injuries;
• injuries that prevent a person from performing their usual work;
• injuries requiring medical attention;
• occupational illnesses; and
• certain prescribed incidents even where no worker has been injured.

The exact recipient and deadline depend on the type of occurrence.

Ontario Regulation 420/21 supports these OHSA requirements by defining terms such as critically injured and medical attention, prescribing information that must appear in certain reports, and establishing additional reporting requirements for particular incidents.

 

Incidents Reportable to WSIB

WSIB reporting is a separate process.

A work-related injury or illness generally has to be reported to WSIB where the worker requires treatment from a health professional, misses regular work, earns less than regular pay, performs modified work at reduced pay, or continues modified work at regular pay for more than seven calendar days after the accident.

The WSIB reporting rules will be covered separately later in this guide because an incident may trigger WSIB reporting even where the Ministry reporting requirements are different.

Ontario Workplace Incident Reporting Deadlines

 

Different reporting obligations use different timelines.

 

Employers should avoid treating “report the incident” as one universal deadline.

 

Situation	Reporting deadline	Who must be notified or receive the report?
Fatality or critical injury	Immediately	Ministry inspector, JHSC or health and safety representative, and trade union if applicable
Written report following fatality or critical injury	Within 48 hours	Ministry Director and prescribed workplace parties
Injury preventing usual work or requiring medical attention, without death or critical injury	Within 4 days	JHSC or health and safety representative and union, with Ministry notice if required by an inspector
Occupational illness	Within 4 days after the employer is advised	Ministry and applicable workplace parties
Certain prescribed incidents under OHSA s. 53	Generally within 2 days	Ministry and applicable workplace parties
WSIB-reportable injury or illness	Within 3 business days after the reporting obligation begins	WSIB
Certain incidents requiring an engineer’s written opinion	Within 14 days	Ministry
Retention of OHSA notices and reports required under ss. 51 to 53.1	At least 3 years	Employer or constructor retains the record

The reporting requirements should always be matched to the specific event. A single incident can trigger more than one line in this table.

When Must a Fatality or Critical Injury Be Reported?

 

A workplace fatality or critical injury creates the most urgent reporting obligations under Ontario’s OHSA.

Section 51 requires the constructor, where applicable, and the employer to immediately notify an inspector, the joint health and safety committee or health and safety representative, and the trade union if there is one.

The Ministry directs employers and constructors to make the immediate notification through its Health and Safety Contact Centre at 1-877-202-0008, which operates 24 hours a day.

A written report must then follow within 48 hours.

Ontario Regulation 420/21 prescribes the information that must be included in this report.

For an employer responding to a serious workplace incident, these are two separate obligations:

Immediate notification comes first.

The detailed written report follows within 48 hours.

Submitting a written report later does not replace the requirement to make the immediate notification.

What Is Considered a Critical Injury in Ontario?

Ontario Regulation 420/21 defines a critical injury as an injury of a serious nature that:

• places life in jeopardy;
• produces unconsciousness;
• results in substantial loss of blood;
• involves the fracture of a leg or arm, excluding a finger or toe;
• involves the amputation of a leg, arm, hand or foot, excluding a finger or toe;
• consists of burns to a major portion of the body; or
• causes loss of sight in an eye.

 

This definition matters because a critical injury triggers the immediate notification and 48-hour reporting requirements under section 51 of the OHSA.

Employers should assess the actual injury against this definition rather than relying only on whether the worker was transported to hospital.

A hospital visit by itself does not determine whether the injury is “critical.” The nature of the injury is what matters.

Does a Broken Wrist Count as a Critical Injury in Ontario?

A wrist fracture can fall within Ontario’s interpretation of a critical injury involving the fracture of an arm.

The Ministry’s reporting guidance should be consulted when there is uncertainty about whether a specific fracture or other injury meets the critical injury definition. Where the facts suggest the injury may qualify, the employer should treat the reporting decision as urgent.

The immediate reporting requirement exists so the Ministry can respond promptly to serious workplace events.

Do Critical Injuries Involving Visitors or Members of the Public Have to Be Reported?

Section 51 is not limited only to injured employees.

Ontario says a fatality or critical injury involving a person who is not a worker may still have to be reported where:

• the event occurred at a place where a worker was working or might reasonably be expected to work; and
• there is a reasonable connection between the hazard that caused the death or critical injury and worker health and safety.

This can matter in workplaces where customers, contractors, delivery drivers, visitors or members of the public enter areas that are also used by workers.

The reporting assessment should therefore consider the location, hazard and connection to worker safety, rather than only the employment status of the injured person.

Can You Disturb the Scene After a Critical Injury or Fatality?

 

Generally, no.

 

When a person is killed or critically injured at a workplace, subsection 51(2) of the OHSA restricts people from interfering with, disturbing, destroying, altering or removing wreckage, articles or things connected with the occurrence until an inspector gives permission.

The Act provides limited exceptions where disturbing the scene is necessary to:

• save a life or relieve human suffering;
• maintain an essential public utility service or public transportation system; or
• prevent unnecessary damage to equipment or other property.

This means employers should think carefully before moving machinery, cleaning the area, removing damaged equipment or resetting a work process after a critical injury or fatality.

Emergency care always takes priority. Once the immediate emergency has been addressed, the scene should be preserved unless one of the statutory exceptions applies or an inspector authorizes changes.

Photos, witness information, equipment position and other evidence can become important during both the Ministry response and the employer’s later investigation.

What Should the Employer Do Immediately After a Critical Incident?

The first response should follow the circumstances of the emergency, but an Ontario employer’s immediate priorities will usually include:

1. Call emergency services where required and provide first aid.
2. Control any continuing danger to workers.
3. Determine whether the event involves a fatality or critical injury.
4. Make the immediate OHSA notifications where section 51 applies.
5. Preserve the incident scene in accordance with OHSA subsection 51(2).
6. Identify witnesses and preserve relevant documents, equipment information and other evidence.
7. Prepare the required written report within 48 hours.
8. Determine whether separate WSIB reporting obligations also apply.

The reporting process should begin while information is still fresh. Serious incidents often involve several obligations at once, and delaying the initial assessment can make it harder to meet statutory deadlines.

Ref:

• Ontario.ca – Reporting Workplace Incidents and Illnesses
• WSIB – Report an Injury or Illness

What Injuries Must Be Reported Within Four Days?

A workplace injury can trigger a written notice under section 52(1) of the Occupational Health and Safety Act even when the injury is not critical.

The four-day requirement applies when a person is:

• unable to perform their usual work; or
• requires medical attention

because of an accident, explosion, fire or incident of workplace violence at the workplace, provided the occurrence did not cause a fatality or critical injury.

The employer must provide written notice within four days of the occurrence to the:

• joint health and safety committee or health and safety representative;
• trade union, if there is one; and
• Director of the Ministry of Labour, Immigration, Training and Skills Development if an inspector requires notification.

This reporting route is different from the immediate notification required for fatalities and critical injuries.

What Does “Unable to Perform Usual Work” Mean?

The reporting trigger focuses on whether the person can perform their normal work following the incident.

An employer should consider the actual duties the person normally performs and whether the injury prevents them from carrying out those duties.

For example, an injured worker may remain at work but be unable to perform their regular job and require different duties. That circumstance can be relevant to the section 52 assessment.

Employers should document:

• the worker’s regular duties;
• the restrictions caused by the injury;
• whether modified duties were provided;
• when the restrictions began; and
• when the worker returned to their usual work.

These details may also become important when determining whether a separate WSIB reporting obligation applies.

What Counts as “Medical Attention” Under the OHSA?

Ontario Regulation 420/21 gives medical attention a specific meaning for these reporting provisions.

It means treatment from:

• a legally qualified medical practitioner; or
• a registered nurse who holds an extended certificate of registration under Ontario’s Nursing Act.

The Ministry describes this second category as a nurse practitioner.

Treatment from another regulated health professional, such as a chiropractor, physiotherapist or naturopath, does not fall within this particular OHSA definition of medical attention.

This distinction matters because the OHSA reporting test and the WSIB reporting test use different terminology and thresholds.

An employer should evaluate each system separately.

How Are Occupational Illnesses Reported in Ontario?

Occupational illness has its own reporting requirement under section 52(2) of the OHSA.

If an employer is advised that a worker has an occupational illness, or that an occupational illness claim has been filed with WSIB, the employer must provide written notice within four days of being advised.

The notice goes to:

• a Director of the Ministry of Labour, Immigration, Training and Skills Development;
• the joint health and safety committee or health and safety representative; and
• the trade union, if applicable.

The requirement also applies when the information concerns a former worker. Section 52(3) extends the occupational illness notice obligation to former workers.

An occupational illness may develop gradually and become apparent long after the original exposure occurred. The four-day period therefore begins when the employer is advised of the illness or relevant WSIB claim, rather than when the exposure originally happened.

Examples may include illnesses associated with workplace exposure to hazardous substances, noise, biological agents or other occupational hazards.

Employers should preserve relevant exposure records, work history and workplace information when an occupational illness is reported. These records may assist both the statutory reporting process and any later investigation into the source of exposure.

When Must an Employer Report an Injury or Illness to WSIB?

WSIB reporting operates separately from OHSA incident reporting.

An Ontario employer generally has to report a work-related accident to WSIB when the employer learns that the worker requires health care or experiences specified work or earnings consequences.

WSIB identifies the following reporting triggers:

• the worker requires health care;
• the worker is absent from regular work;
• the worker earns less than regular pay for regular work;
• the worker performs modified work at less than regular pay; or
• the worker performs modified work at regular pay for more than seven calendar days following the accident.

This means a relatively minor workplace injury can create a WSIB reporting obligation even when it never reaches the threshold for a critical injury or another Ministry reporting trigger.

What Does WSIB Mean by Health Care?

WSIB’s definition of health care is broader than the OHSA definition of medical attention discussed earlier.

For WSIB purposes, health care can include professional services provided by health care practitioners such as:

• doctors;
• nurses;
• chiropractors; and
• physiotherapists.

It can also include hospital or health-facility services and prescription drugs.

This is an important distinction.

A treatment that does not meet the OHSA definition of “medical attention” may still create a WSIB reporting obligation.

Employers should therefore assess the OHSA and WSIB requirements independently after an injury.

When Does an Employer Have Three Business Days to Report to WSIB?

Once the WSIB reporting obligation has been triggered, WSIB must receive the employer’s complete accident report within three business days after the employer learns of the reporting obligation.

Business days run Monday through Friday and exclude statutory holidays.

The date the reporting clock starts depends on what happens after the incident.

For example, if a worker seeks health care on the day of the injury, the reporting obligation begins at that point.

If the worker initially remains at work on modified duties at regular pay and does not seek health care, the reporting obligation may arise later if the modified work continues beyond the applicable seven-calendar-day period.

Employers should document when they first became aware of the facts that created the reporting obligation.

How Does the Seven-Day Modified Work Rule Work?

WSIB has a specific rule for workers performing modified work at their regular rate of pay.

An employer generally must report the accident if the worker requires modified work at regular pay for more than seven calendar days following the date of accident.

The seven-day period uses calendar days rather than scheduled shifts.

This matters for workers with irregular schedules.

If the employee is not scheduled to work on the eighth calendar day, WSIB says the reporting obligation can arise when the worker requires modified work on the first shift following that eighth day.

The period also does not automatically restart when a worker briefly returns to regular duties and later requires modified work again.

Employers should monitor the worker’s duties and restrictions throughout the return-to-work process rather than treating the initial assignment of modified duties as the end of the reporting assessment.

When Is WSIB Reporting Usually Not Required?

WSIB says an employer generally does not need to report an accident where the worker:

• receives only first aid;
• receives first aid and performs modified work at regular pay for seven calendar days or less; or
• performs modified work at regular pay for seven calendar days or less without receiving first aid.

Special reporting rules can apply in particular circumstances, including certain occupational exposures.

Employers should assess the facts of the individual case when symptoms, health care or work restrictions change after the initial incident.

Is WSIB Form 7 Still Used in Ontario?

Employers may still hear the term Form 7 because it has historically referred to the Employer’s Report of Injury/Disease.

WSIB’s current employer-facing process has changed.

As of August 11, 2026, WSIB states that the PDF Employer’s Report of Injury/Disease, Form 7, is no longer available. Employers are now directed to report workplace injuries and illnesses through WSIB’s online reporting services.

The reporting obligation itself remains.

The current online process asks employers for information covering areas such as:

• injury or illness details;
• where the event occurred;
• business information;
• worker information and employment history;
• health care received or planned;
• lost time;
• modified duties;
• earnings; and
• supporting documents.

WSIB provides a reference number during the online reporting process so the employer can save the report and return to it if additional information is required.

Employers with older incident-reporting policies that still direct supervisors to download and complete a Form 7 PDF should update those procedures to match the current WSIB process.

OHSA Reporting and WSIB Reporting Are Separate Requirements

One of the easiest mistakes to make after a workplace injury is assuming that one report satisfies every legal obligation.

Ontario’s OHSA reporting requirements and WSIB reporting requirements serve different functions.

Consider a worker who suffers an injury and receives professional health care.

The employer may need to determine:

• whether section 51 applies because the injury is critical;
• whether section 52 applies because the worker requires medical attention or cannot perform their usual work;
• whether a written notice must go to the JHSC, health and safety representative or union;
• whether Ministry notification is required; and
• whether the injury also meets WSIB’s reporting threshold.

These questions should be assessed separately.

OHSA vs. WSIB Reporting at a Glance

Issue	OHSA / Ministry reporting	WSIB reporting
Main purpose	Occupational health and safety notification and regulatory oversight	Workplace insurance claim and benefit administration
Primary trigger	Nature and consequences of the incident under OHSA ss. 51 to 53.1	Work-related injury/illness plus health care, lost time, earnings impact or qualifying modified work
Critical injury	Immediate notification plus 48-hour written report	May also require WSIB reporting
Medical threshold	Uses the O. Reg. 420/21 definition of “medical attention” for s. 52	Uses WSIB’s broader definition of health care
Modified work	Can be relevant to whether usual work can be performed	Specific seven-calendar-day rule applies in some regular-pay modified-work cases
Reporting

 

References

Ontario workplace incident reporting guidance: Ontario.ca – Reporting Workplace Incidents and Illnesses
CCOHS incident investigation resources: CCOHS – Incident Investigation

Which Incidents Can Be Reportable Even If Nobody Is Injured?

Some Ontario workplaces have reporting obligations for specified incidents even when nobody is killed or injured.

These requirements come primarily from section 53 of the OHSA and section 4 of O. Reg. 420/21. They apply to particular sectors and types of occurrences rather than every workplace near miss.

This distinction matters.

A routine near miss in a warehouse may be handled through the employer’s internal reporting and investigation process. A prescribed equipment failure or dangerous occurrence on a construction project, mine, diving operation or workplace covered by X-ray safety regulations can create an external reporting requirement even though nobody was hurt.

Reportable Incidents on Ontario Construction Projects

For construction projects governed by O. Reg. 213/91, section 53 reporting can apply where there is:

• an accident;
• a premature or unexpected explosion;
• a fire;
• a flood or inrush of water;
• a cave-in or subsidence;
• a rockburst; or
• a failure of equipment, machinery, a device, article or other thing that could have posed a risk to a worker’s life, health or safety.

The constructor generally has the reporting responsibility for these construction-project occurrences.

Written notice is required within the applicable statutory timeframe, generally within two days of the occurrence under section 53.

These requirements are useful to keep separate from ordinary near-miss reporting because the legal trigger is the specified event itself.

Other Prescribed Incidents

O. Reg. 420/21 also contains specific reporting requirements relating to:

• mines and mining plants;
• diving operations; and
• workplaces covered by Ontario’s X-ray safety regulation.

The exact trigger depends on the sector.

For example, the regulation identifies events such as certain diving-equipment failures, emergency diver rescues and specified radiation-exposure incidents. Employers working in these sectors should review the applicable subsection rather than relying on a general workplace incident procedure.

When Is an Engineer’s Written Opinion Required?

Some serious incidents require an additional report from an engineer.

Section 53.1 of the OHSA, together with section 5 of O. Reg. 420/21, requires an engineer’s written opinion stating the cause of the occurrence in specified circumstances.

On a construction project, this can include an incident involving the failure of:

• temporary or permanent works;
• a structure;
• certain excavation walls or similar earthworks;
• a crane or similar hoisting device; or
• control of a crane or load, including a rigging failure.

Similar additional reporting requirements can apply to certain structural failures at health care or residential facilities and during window-cleaning operations.

The engineer’s written opinion must be provided within 14 days after the occurrence.

This report supplements the initial notice or report. It does not replace an earlier obligation under sections 51, 52 or 53.

What Information Must an Ontario Workplace Incident Report Contain?

Ontario Regulation 420/21 prescribes information that must be included in written reports and notices submitted under sections 51 and 52 of the OHSA.

Depending on the type of occurrence, the required information can include:

• the employer’s name, address and type of business;
• the worker’s name and address or other identifying information where applicable;
• the nature of the injury or occupational illness;
• the circumstances surrounding the occurrence;
• the machinery, equipment or procedure involved;
• the time, date and location of the occurrence;
• the cause or suspected cause of an occupational illness;
• the names and contact information of witnesses; and
• the steps taken to prevent a recurrence or further illness.

Section 53 notices for prescribed incidents use a related set of information, including the nature and circumstances of the event, equipment or procedures involved, and measures taken to prevent recurrence.

The Ministry provides an online process that can be used to submit applicable written reports and notices. O. Reg. 420/21 expressly permits the statutory written-report requirement to be satisfied through a Government of Ontario website where the appropriate form is available.

What Should an Internal Incident Investigation Record Include?

The statutory notice is only one part of the employer’s documentation.

An internal investigation may require more detail so the workplace can understand why the incident occurred and determine what needs to change.

Depending on the event, useful information can include:

• photographs of the scene;
• witness statements;
• equipment condition;
• maintenance records;
• training and competency records;
• work procedures in effect at the time;
• supervision arrangements;
• environmental or site conditions;
• personal protective equipment being used;
• events leading up to the incident;
• identified contributing factors;
• corrective actions assigned; and
• dates showing when corrective actions were completed.

The purpose is to create an accurate record that supports prevention.

The investigation should look beyond the immediate act that preceded the incident. Equipment design, procedures, staffing, training, maintenance, supervision and workplace conditions can all contribute to an event.

Where the incident requires a detailed investigation, employers may benefit from personnel who understand evidence collection, interviewing, causal analysis and corrective-action development.

How Long Must Workplace Incident Reports Be Kept in Ontario?

O. Reg. 420/21 requires an employer or constructor to retain a copy of any written notice or report required under sections 51 to 53.1 of the OHSA for at least three years after the report or notice is made.

This three-year requirement applies to the statutory notice or report.

Other workplace records may have different retention requirements under separate legislation, regulations, WSIB policies or company procedures.

Employers should therefore avoid using three years as a universal retention period for every document connected with an incident.

A practical incident file may contain several categories of records, including:

• the statutory OHSA notice or report;
• WSIB reporting documentation;
• internal investigation records;
• witness statements;
• photographs;
• corrective-action records;
• equipment inspection or maintenance records; and
• worker training documentation.

Keeping these records organized around the incident makes later review easier and helps demonstrate how identified hazards were addressed.

What Should an Employer Do After the Initial Incident Report?

Submitting the required notice does not resolve the underlying workplace hazard.

Once emergency response and statutory reporting have been addressed, the employer should determine what caused the event and what needs to change before similar work continues.

A practical response typically includes the following steps.

1. Preserve Relevant Evidence

Secure documents, equipment information, photographs, video, witness details and other evidence before conditions change.

Where OHSA scene-preservation requirements apply, those requirements take priority.

2. Confirm Every Reporting Obligation

Review the event against:

• OHSA section 51;
• OHSA section 52;
• occupational illness requirements;
• section 53 prescribed incidents;
• any section 53.1 engineer-report requirement;
• O. Reg. 420/21; and
• WSIB reporting rules.

One event can trigger several obligations.

3. Investigate What Happened

Determine the sequence of events and contributing conditions.

Interviews should focus on obtaining factual information. Equipment, procedures, training, supervision, workplace layout and environmental conditions may all need review.

4. Identify Corrective Actions

Corrective measures should respond to the factors discovered during the investigation.

Depending on the incident, actions may involve:

• repairing or replacing equipment;
• changing a work procedure;
• revising traffic or access controls;
• providing additional training;
• improving supervision;
• updating inspections;
• redesigning a work area; or
• introducing additional engineering controls.

5. Verify That Corrective Actions Were Completed

Assign responsibility and completion dates.

An action item that remains open does not control the hazard.

Employers should confirm that the corrective measure was implemented and determine whether it is working as intended.

For workplaces that need to strengthen their investigation process, Achieve Safety’s Accident and Incident Investigation Training can help supervisors and safety personnel develop a structured approach to evidence collection, causal analysis and corrective action.

Ontario Workplace Incident Reporting Checklist for Employers

Use this checklist after a workplace injury, illness or serious incident to determine the next steps.

Immediate response

• Provide first aid and emergency medical assistance where required.
• Call 911 where appropriate.
• Control any immediate danger to workers.
• Determine whether anyone has died or suffered a critical injury.
• Preserve the scene where OHSA subsection 51(2) applies.

Determine the OHSA reporting requirement

• Does the incident involve a fatality or critical injury?
• Is immediate Ministry notification required?
• Is a 48-hour written report required?
• Is the person unable to perform their usual work?
• Did the person require medical attention as defined by O. Reg. 420/21?
• Is a four-day section 52 notice required?
• Has the employer been advised of an occupational illness?
• Is the event a prescribed section 53 incident?
• Is an engineer’s written opinion required within 14 days?

Check workplace-party notifications

Determine whether notice must also go to:

• the joint health and safety committee;
• the health and safety representative; and
• the trade union, where one exists.

Check WSIB requirements separately

Ask whether the worker:

• received health care;
• lost time from regular work;
• received less than regular pay;
• performed modified work at reduced pay; or
• continued modified work at regular pay beyond seven calendar days.

If the WSIB reporting obligation exists, ensure the report is submitted within the applicable three-business-day deadline.

Document and investigate

• Preserve relevant evidence.
• Identify witnesses.
• Record the equipment and procedures involved.
• Determine contributing factors.
• assign corrective actions.
• Verify completion.
• Retain statutory OHSA notices and reports for at least three years.

The checklist should be adapted to the employer’s workplace, industry and applicable regulations.

Frequently Asked Questions About Workplace Incident Reporting in Ontario

Do All Workplace Injuries Have to Be Reported to the Ministry of Labour?

No. Ministry reporting depends on whether the incident meets one of the reporting triggers under Part VII of the OHSA.

Fatalities and critical injuries require immediate notification and a written report. Other injuries may require a four-day notice where the person cannot perform their usual work or requires medical attention. Occupational illnesses and certain prescribed incidents have separate reporting requirements.

Minor injuries that do not meet one of these statutory triggers may still require internal documentation or WSIB reporting depending on the circumstances.

Does First Aid Have to Be Reported to WSIB?

An injury that requires only first aid generally does not have to be reported to WSIB when no other reporting trigger exists.

The situation should be reassessed if the worker later seeks health care, loses time, experiences reduced earnings or requires modified duties beyond the applicable reporting threshold.

An employer’s internal procedure may still require the first aid incident to be documented.

How Long Does an Employer Have to Report a Workplace Injury in Ontario?

There is no single deadline for every workplace injury.

Depending on the event, the applicable requirement may be:

• immediately for a fatality or critical injury;
• 48 hours for the follow-up written report;
• four days for certain injuries and occupational illnesses;
• two days for specified section 53 incidents;
• three business days for a WSIB-reportable injury or illness once the reporting obligation exists; or
• 14 days for an engineer’s written opinion where section 53.1 applies.

Employers should identify the reporting trigger before calculating the deadline.

Do Near Misses Have to Be Reported to the Ministry?

An ordinary workplace near miss does not automatically require Ministry notification.

It should still be reported internally where required by the workplace program so the hazard can be investigated and corrected.

Some incidents are specifically reportable under section 53 and O. Reg. 420/21 even where nobody was injured. These sector-specific rules can apply to construction projects, mines and mining plants, diving operations and X-ray workplaces.

Can Workplace Incident Reports Be Submitted Online?

Yes. O. Reg. 420/21 provides that written reports or notices required under sections 51 to 53.1 can be submitted through a Government of Ontario website where the applicable form is provided.

An electronic copy of that submission can also satisfy applicable notice requirements to the joint health and safety committee, health and safety representative and trade union.

How Long Must an Employer Keep an OHSA Incident Report?

An employer or constructor must retain a copy of a written notice or report required under OHSA sections 51 to 53.1 for at least three years from the date the notice or report was made.

Other records connected with the incident may be subject to different retention requirements.

Build a Reporting Process Before an Incident Happens

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At Achieve Safety, Ontario Health & Safety Consulting Provider, we help organizations design, implement, and maintain effective Accident Reporting and Investigation Programs that meet Ontario’s health and safety laws.

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