Glossary of Terms



As defined in the OPR, “incident” means an occurrence that results in

  • (a) the death or serious injury to a person;
  • (b) a significant adverse effect on the environment;
  • (c) an unintended fire or explosion;
  • (d) an unintended or uncontained release of low vapour pressure (LVP)Footnote 1 hydrocarbons in excess of 1.5 m³;
  • (e) an unintended or uncontrolled release of gas or high vapour pressure (HVP)Footnote 2 hydrocarbons;
  • (f) the operation of a pipeline beyond its design limits as determined under CSA Z662 or CSA Z276 or any operating limits imposed by the Board.

As defined in the PPR, “Incident” is defined as an occurrence that results or could result in a significant adverse effect on property, the environment, or the safety of persons.

For the purposes of incident reporting in the PPR, events that fall under this definition include, but are not limited to:

  • the death of or serious injury to a person;
  • a significant adverse effect on the environment;
  • an unintended fire or explosion that results in or has the potential to result in damage to company, public/crown or personal property;
  • an unintended or uncontained release of LVP liquids in excess of 1.5 m³;
  • an unintended or uncontrolled release of gas, HVP hydrocarbons, hydrogen sulfide or other poisonous gas; or
  • the operation of a plant beyond its design limits or any limits imposed by the Board.

Significant Incident

A significant incident is an acute event that results in:

  • death;
  • a serious injury (as defined in the OPR);
  • a fire or explosion that causes a pipeline or facility to be inoperative;
  • a LVP hydrocarbon release in excess of 1.5 m³ that leaves company property or the right-of-way;
  • a rupture; or
  • a toxic plume (as defined in CSA Z662).

Serious Injury

As defined in the OPR, “serious injury” includes an injury that results in

  • (a) the fracture of a major bone;
  • (b) the amputation of a body part;
  • (c) the loss of sight in one or both eyes;
  • (d) internal hemorrhage;
  • (e) third degree burns;
  • (f) unconsciousness; or
  • (g) the loss of a body part or function of a body part.

Significant Adverse Effect on the Environment

A significant adverse effect on the environment occurs when any chemical substance is released at a concentration or volume that has the potential to change the ambient environment in a manner that would cause harm to human life, wildlife or vegetation (e.g., glycol, potassium carbonate, methanol, methanol mix from hydrostatic testing, etc.).

Operation Beyond Design Limits

This incident occurrence includes situations such as:

  • over pressures;
  • vibration beyond design limits;
  • slope movements causing movement in the pipeline beyond design limits;
  • pipe exposures in rivers or streams; and
  • introduction of an inappropriate product (e.g., sour gas in excess of CSA limits).

Operation beyond design limit is typically linked to an over-pressure of the product in the pipe; however, if a pipe was exposed to excessive vibration and was not designed for this, this could be considered operation beyond design limits. Operation beyond design limits does not include equipment contacting the pipe, or corrosion pits, etc.

Incident Causes

Incident causes are the circumstances and factors that lead to the occurrence of an incident. Incidents have immediate (what happened) and basic causes (why it happened). These causes have been grouped into categories to for ease of reference and for presentation purposes.

What Happened

The circumstances that directly led to the incident

  • Defect and Deterioration – Defects in manufacturing processes or materials, or deterioration as a result of damage or service life limitations, lack of inspection or maintenance
  • Corrosion and Cracking – External corrosion or cracking caused by damage to coating systems or failed coating systems; weld cracking as a result of stress or workmanship issues; or internal corrosion as a result of contaminates in products
  • Equipment Failure – A failure of the pipeline’s equipment components. Examples of equipment include valves, electrical power systems and control systems
  • Incorrect Operation – Typically, personnel fail to follow procedures or use equipment improperly
  • External interference – External activities that cause damage to the pipeline or components. Examples include excavation damage and vandalism
  • Natural Force Damage – Damage caused by natural forces, such as earthquakes, landslides and wash-outs
  • Other Causes – All other causes or when an incident’s circumstances could not be determined

Why It Happened

The underlying reasons for the incident

  • Engineering and Planning – Failures of assessment, planning or monitoring that may be related to inadequate specifications or design criteria, evaluation of change, or implementation of controls
  • Maintenance – Inadequate preventive maintenance or repairs, and excessive wear and tear
  • Inadequate Procurement – Failures in the purchasing, handling, transport and storage of materials
  • Tools and Equipment – Tools and equipment that are inadequate for the task or used improperly
  • Standards and Procedures – Inadequate development, communication, maintenance or monitoring of standards and procedures
  • Failure in communication – Loss of communication with automatic devices, equipment or people
  • Inadequate Supervision – Lack of oversight of a contractor or employee during construction or maintenance activities
  • Human Factors – Individual conduct or capability, or physical and psychological factors
  • Natural or Environmental Forces – External natural or environmental conditions

Toxic Plume

A toxic plume is typically used in reference to a gas release but it also may be a liquid release into water or soil. A toxic plume is defined in CSA Z662 as a toxic or asphyxiating column or band of service fluid moving from a point of release through the air, soil or water.

Unauthorized Activities

Unauthorized Activity

An unauthorized activity is any activity required to be reported by a regulated pipeline company to the NEB under subsection 11(1) of the National Energy Board Pipeline Damage Prevention Regulations – Obligations of Pipeline Companies, and includes:

  • every contravention of the National Energy Board Pipeline Damage Prevention Regulations – Authorizations;
  • all damage to its pipe caused or identified during the construction of a facility across, on, along or under a pipeline, the operation, maintenance or removal of a facility, an activity that caused a ground disturbance within the prescribed area or the operation of vehicles or mobile equipment across the pipeline; and
  • any activity related to the construction of a facility across, on, along or under a pipeline, an activity that caused a ground disturbance within the prescribed area or the operation of vehicles or mobile equipment across a pipeline that the pipeline company considers could impair the safety or security of the pipe.

Ground Disturbance

Ground disturbance refers to an activity that moves or penetrates the ground. However, under section 2 of the NEB Act, ground disturbance does not include:

  • cultivation to a depth of less than 45 cm below the surface of the ground
  • any activity to a depth of less than 30 cm and that does not result in reduction of the earth cover over the pipeline to a depth that is less than the cover provided when the pipeline was constructed

Activities causing ground disturbance can include, but are not limited to, the following:

  • digging
  • excavation
  • trenching
  • ditching
  • tunneling
  • plowing to install underground infrastructure
  • tree planting
  • blasting/use of explosives

Prescribed Area or Safety Zone

The prescribed area, as defined in the National Energy Board Pipeline Damage Prevention Regulations – Authorizations (DPR – Authorizations) is a strip of land measured 30 metres perpendicularly on each side from the centreline of a pipe.
This is the safety zone where the regulations apply and that safety measures must be met for activities causing a ground disturbance.

Right of Way (ROW)

The strip of land acquired for which a pipeline company has obtained the rights for the construction and operation of the pipeline.


Excavation includes any operation using equipment, explosives or other means to move earth, rock or other material below the existing grade.

Constructing a Facility

Constructing a facility refers to the placement of a facility across, on, along or under the pipeline. This includes, but is not limited to, placing or storing equipment (mobile or otherwise), outbuildings, skating rinks, swimming pools, sheds, gazebos, woodpiles, berms or any other structure on the ROW.

Vehicle Crossing

Vehicle crossing is the operation a vehicle or mobile equipment across, or on a right-of-way. Occurrences that fall into this category include operation of heavy equipment or trucks across the right-of-way, with the exception of any vehicle operating across the right-of-way on the travelled portion of a highway or a public road.


The sub-type for the unauthorized activity has not yet been determined.

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