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Nova Scotia

Conducting an Effective Incident Investigation

An effective incident investigation can help prevent similar incidents and future injuries.  Rarely is there only one cause for an incident. By finding the causes and taking steps to control or eliminate them, similar occurrences can be avoided.

Always keep in mind that effective incident investigation means fact-finding – not fault-finding.

Select an investigation team

By identifying a team of investigators, you can respond quickly to any incident, injury, or illness. The team should be representative of your workplace and have a cross-section of skills and abilities. It should be large enough that it can still be operational if one or two members are absent at any time.

Train your investigation team

A number of important skills are involved in conducting an incident investigation. Training in incident investigation is strongly recommended.  Training the investigation team in advance can help ensure the investigations are effective, that the team members have the necessary skills, and that they understand their roles before being faced with an actual incident.  A listing of OH&S training providers in Nova Scotia is available online or by calling the OHS Division at (902) 424-5400 or toll-free within Nova Scotia at 1-800-952-2687.

Assemble investigation tools

The following items can be very helpful to the investigation team.  Keep them together in an easy-to-carry container that will protect them from damage so they’re readily available if needed:

  • tape measure
  • clipboard, pens or pencils, paper (square or graph paper is recommended for illustrations)
  • equipment tags for labelling
  • flashlight and batteries
  • emergency phone numbers (police, ambulance, fire, OHS Division)
  • barrier tape
  • camera and flash
  • incident investigation forms
  • investigation checklist

Steps in an incident investigation

Step 1: Emergency response

This is the first step in response to any incident. When an incident occurs, the danger may not be limited to those directly involved. In the case of a gas leak or a fire, for example, other workers and the general public may also be threatened. Your first priority is your workers—both those injured and those who may be in danger.

What you do Why you do it
Take Charge. Do not panic. Reduces confusion and establishes control.
You must get help before rescuing.  Call your first aid attendant and 911 if needed.  Relay as much information as possible.
Ensure clear access for emergency personnel.  Have someone meet emergency responders and guide them as close to the scene as safely possible.
The quicker emergency medical personnel respond, the better the outcome for the injured person.
Immediately assess the seriousness of the situation.  Ask:  Can the present situation get worse? Is anybody injured? How can damage be minimized? Prioritizes need, prevents other injury, minimizes property damage.
Don’t become a casualty yourself!  Never rush into an incident scene without first evaluating potential risks. Where safely possible, eliminate and contain potential hazards.  Remove all non-essential people from the danger area.
Don’t let one injury turn into multiple injuries.  In an emergency, you must ensure that the hazard has been contained before any rescue is made.  This is especially important if electricity, fire, gas or confined space are involved.
 Provide first aid as soon and as safely as possible. Helps stabilize and improve condition of injured people until professional medical help can be obtained.
 Find out where injured people are being taken. Provides Information for families ad investigators.
Inform senior management and, when necessary, the OHS Division.
Do not disturb the accident scene until the investigation is complete, or an OHS Officer has said otherwise.
Meets regulatory requirement for notification when there has been a critical injury, when a worker has lost consciousness, or following any other situation as defined by legislation.

Step 2: Secure and Identify witnesses

After the injured have been tended to and there is no further threat, your next priority is to secure the scene and identify potential witnesses.

Witnesses can disperse quickly and never be seen again. This is especially true when passers-by have witnessed an incident, for example, at a construction site. A good witness can provide an accurate description of the incident.

It’s important to identify and interview anyone who saw the incident or was in the vicinity immediately before, during, or after the incident—including any workers who may have been injured.

What you do  Why you do it
Control the crowd. Ask someone to assist. Ask onlookers whether they know how the incident happened. Identify witnesses. Tell them that their help will be needed later. If the incident occurred in a room, keep onlookers outside. Post someone outside until a barricade can be erected. Stabilizes the situation, slowly bringing it back to normal. While a crowd can hinder an investigation and needs to be controlled, it can also provide valuable witnesses.
Secure area until the investigation is completed. Physically isolate the incident by locking, taping or fencing off the area. Ensures that the scene and evidence will not be disturbed. Allows investigators to go back to the scene and assess what may have been missed or overlooked.
If possible, ask emergency crews to leave material where they found it. Only move and remove what is absolutely necessary to assist the injured or to protect property from further damage. Helps investigators to establish facts rather than make assumptions.
List those directly involved in the incident. If the public is involved, go to them first as they will likely be first to leave. For future contact.
Ask those first on the scene to help develop a witness list and approach those witnesses immediately. Best chance at finding out who else was in the vicinity at the time of the incident.
Tell all witnesses that the purpose of the investigation is fact-finding, not fault-finding. Tell them that their help is needed to prevent the incident from happening again. Witnesses may be reluctant to participate. They may be afraid of being blamed or feel they must point a finger at one of their co-workers. Assuring witnesses will encourage them to come forward and volunteer information.
Arrange interviews for as soon as possible. More information is forthcoming when memories are still fresh.
Ask each witness for a list of who may have seen or have knowledge of the incident. Contact these witnesses if necessary. Extends network of information.

Step 3: Survey the scene

Survey the incident scene as soon as possible. This is especially critical when the incident happened outdoors because evidence such as slip, tire, or impact marks can be wiped out by weather conditions.'

Your objectives in surveying the scene include:

  • collecting and double-check evidence
  • confirming witness statements
  • determining inconsistencies
  • establishing the cause

Use measuring tape, camera, and sketches to record the scene as found.

Subject Considerations
- Conditions
- Temperature
- Visibility
Extreme high or low temperatures or high winds may put workers in danger. Poor light may limit workers’ vision and restrict communication. Glare or bright flashes of light can temporarily blind workers.
Incident surroundings:
- Are there marks that could provide clues to the incident?
- Anything out of the ordinary?
Skid marks or scratches on the floor can be keys to more evidence and contribute significantly to the investigation.
Work site:
- Were floor and work areas clear and dry?
- Was there a risk of slipping?
- Could debris cause trips and falls?
- Was the work area too confined?
- Was access clear and open?
Slippery floors may not give workers or equipment proper footing. Lack of space may create additional materials handling hazards or make workers work closer to the equipment than recommended.
Equipment, materials and tools:
- Confirm location in relation to injured worker.
- Match damage or other marks on equipment or tools to damage or marks on floors and walls.  Are they consistent?
- Check safety devices such as guardrails and safety catches.
- Are machinery controls on or off?
- Photograph and record nameplate data, such as weights and load limits.
- Check for equipment malfunction.
- Check for structural damage as well as damage to equipment, piping, etc.
Safety guards are often removed.

Establish consistency.

Verify that what was said is correct.  If not, there may be some problem with machine, equipment, or someone’s familiarity with machine or equipment.

Step 4: Prepare a report

When all of the information has been collected and reviewed, and the causes of the incident have been identified, it is time to make recommendations for corrective actions to prevent similar occurrences.

The incident investigation report should be signed by the lead investigator and dated, and should contain the following information:

  • Location, date and time of incident—and weather conditions, if relevant
  • Description of incident, including people, equipment, material, and machinery involved
  • Names and addresses of the injured, and the nature of the injuries
  • Names and addresses of other people involved
  • Names and addresses of workplace owner
  • Materials damage, including costs
  • Names and addresses of witnesses
  • Attending physician, if any
  • First Aid attendant, if any
  • Immediate and underlying causes
  • Recommendations for corrective action

The recommendations for corrective action made in the report must be evaluated and implemented by those with authority in the workplace

Remember to report near misses too

What caused a near miss today could result in a serious injury tomorrow.

Don’t wait for a hazard to become an injury before investigating. Look into near misses just as you would more serious incidents, and document what happened. Near misses don’t require the same reporting procedures as more serious incidents, but they still warrant some degree of investigation. Depending on their severity, the investigation may range from a quick assessment of the situation and a fix, to an in-depth investigation with interviews. Apply the same principles to every case—be thorough, be complete, and be accurate.

Encourage your workers to report near misses and close calls, and ask for their input on ways to prevent near misses from becoming more serious incidents. Work with the health and safety representative and your workers to come up with a way of reporting near misses that works for everyone in your workplace.

© 2021 Workers’ Compensation Board of Nova Scotia & Nova Scotia Department of Labour, Skills and Immigration