4 Types of Evidence During a Root Cause Analysis Investigation
There are four types (or categories) of evidence to be evaluated. TapRooT® investigators call these categories 3 Ps and an R. This stands for:
- People evidence
- Paper evidence
- Physical evidence
- Recording evidence
Often, evidence collection starts with people evidence (a witness statement), and that evidence guides the investigator to collect paper, physical and recording evidence.
Examples of people evidence include:
- Fatigue-related information
- Evidence of injuries, including cuts and scrapes, bruises, fractures, or sprains
- Information about medical conditions that may have influenced performance (refer to HR or corporate counsel for guidance on HIPPA)
Where do you begin? First determine who was involved. This includes those who planned the work, supervised the work and performed the work. Other considerations include a worker’s capability, capacity, training, and qualification to perform his or her role.
Inquire into the background of those involved. Determine if they have been involved in any previous incidents or if they have any related performance or conduct issues. Find out if those involved had any work restrictions such as an impairment, physical capability, or lapsed accreditation.
Understand how the employees worked together. What were the dynamics of the team including supervision and team performance. Determine the context (such as environmental conditions, distractions or perspectives).
Paper evidence may include all sorts of things including:
- Regulatory paperwork
- Activity-specific paperwork
- Personnel paperwork
- Policy and procedure paperwork
- Equipment manuals
What do you think the biggest mistake is when it comes to collecting paper evidence… given all of the paper that we have in our workplaces? Collecting too much paper not relevant to the investigation!
You don’t need to collect every piece of paper at your facility. How do you know what you don’t need? By looking at the timeline of events that led to the incident. You need all the paper that supports your timeline of events and supports the facts. If you use TapRooT®, you can easily upload digital copies of this paperwork, and highlight relevant pages in your report to management.
Don’t make the mistake of collecting so much paper that what you need for evidence is somewhere at the bottom of the stack.
Physical evidence can range from a very large piece of machinery to a very small tool. It includes hardware and solid material related to the incident. You will gather physical evidence in one of two ways. You will collect it or you will record/document evidence that can’t be collected (for example, it is too large to collect, or it is still in use).
Types of physical evidence to collect:
- Broken equipment / parts
- Residue / debris
- Fluid samples
- Paint samples
- Hair, bloodstains, tissue or other DNA
Types of physical evidence to record/document
Evidence is recorded when it is impossible to collect or when it is still in use by the workforce. Following is a list of possible evidence to collect by recordings:
- Burn marks and flame patterns
- Products in use
- Equipment status (fixed, portable or temporary?)
- Lights, noise and temperature
- Confined space
- Surface hazards
- Clarity of signs and labels
Following are additional pieces of information you may want to collect:
- Failure history
- Modification / change of use
- Operator interface
- Maintenance records
- Installing / commissioning
- Storage / transportation
- Design / fabrication
Recording evidence, such as photography and video, should be captured as soon as possible after an incident to preserve the scene in images before it is altered in any way. It provides a documented overview of the entire scene. This may occur as soon as you or a qualified team member can obtain access to the scene.
In addition to video and photography recorded by the investigator, recordings include:
- Video footage (examples: site security cameras, control room cameras)
- Audio recordings (examples: an audio of the noise level, voicemail recordings)
- Photos (examples: cell phone photos captured by bystanders to the incident, photos taken before the incident occurred)
- Computer data (example: magnetic swipe card system security data for entry doors, computerized data from process equipment)
- Sketches of an incident scene
As you record the scene, ask “Am I recording the scene as it was in its original state or has it changed in any way?” If the scene has changed, make a note about what has changed. Identify fragile, perishable evidence and immediately document, photograph and collect it. Also, make a note of any transient evidence that can’t be captured by camera or video like smells and temperature.
Remember, the best way to collect unbiased evidence is to gather evidence from each of the four categories: people, physical, paper and recordings. Each piece of evidence collected will lead you to the truth of the incident so that you can identify problems and analyze root causes for effective corrective actions.
Join us and TapRooT® for a webinar on enabling a human factors-based incident investigation lifecycle. Click on the image below to register: