Safety record
Key Performance Indicators
Pipelines are the safest way to transport liquid energy with 99.999% of barrels delivered by pipeline arriving at their destinations safely. However, no form of transportation is perfect and pipeline incidents can and do happen.
Tracking how, where and why pipeline incidents occur helps pipeline operators and government regulators see how safely pipelines are operating and the reasons behind pipeline incidents when they occur. Pipeline operators use this data to design safety improvement programs. Particularly useful measures of pipeline safety examine incident size, location, commodity and cause.
The liquids pipeline industry also tracks a core set of Key Performance Indicators (KPIs) as a sign of overall pipeline safety performance. These KPIs are based primarily on incidents impacting the people or the environment (IPE). They were created through a collaborative effort between PHMSA, public safety advocates represented by the Pipeline Safety Trust and the liquids pipeline industry. They reflect the highest priority we place on protecting people and the environment.
Incidents Impacting People or the Environment
Pipeline incidents impacting people or the environment decreased 31 percent over the last 5 years. Total pipeline incidents were down as well, dropping 17 percent over 5 years with 70 fewer incidents in 2021 compared to 2017.

Integrity Management Incidents Impacting People or the Environment
Incidents related to the pipeline itself, such as corrosion, cracking, or weld failure, were down 32 percent over the last 5 years in areas impacting people or the environment. In these areas, corrosion failures are also down 32 percent from 2017 to 2021.

Operations & Maintenance Incidents Impacting People or the Environment
Incidents related to maintaining pipeline equipment or operating the pipeline and its valves or pumps were down 34 percent over the last 5 years in areas impacting people or the environment. In these areas, incidents caused by incorrect operations decreased by 38 percent while equipment failure decreased 13 percent from 2017 to 2021.
Incidents by Cause
Over the last 5 years, equipment failure represented 48 percent of incidents, corrosion failure 19 percent and incorrect operation 15 percent of incidents. While equipment failure is the most frequent cause of total incidents, the majority of these incidents are smaller volume and contained within operator facilities with no impact to people or the environment. Material pipe/weld failures, which include cracking, a primary source of large volume releases, represented only 6 percent of incidents since 2017.

Incidents by Commodity
Crude oil incidents impacting people or the environment in 2021 represented 33 percent of the total, with refined products reflecting 67 percent of released barrels from liquids pipelines.

Incidents by Location
Liquids pipeline incidents occurring in high consequence areas (HCAs) declined 16 percent over the last 5 years. Through federal regulation, PHMSA defines HCAs as areas of population concentration, commercially navigable waterways, or sensitive environmental locations. Fewer than half (43 percent) of pipeline incidents occurred in HCAs in 2021. HCA data differs from incidents impacting people or the environment, because under PHMSA regulation an incident can have no impact on people or the environment, remain wholly within an operator’s facility, and still count as an HCA if that facility is surrounded by an HCA.

Incidents by Size
Most pipeline incidents are small in size. In 2021, 66 percent of incidents were less than 5 barrels and 84 percent were less than 50 barrels. Large pipeline incidents are also the rarest. In 2021, only 6 percent of incidents were 500 barrels or larger and these large incidents are down 16 percent over the last 5 years.
