NTSB Press Release

National Transportation Safety Board
Office of Public Affairs


November 29, 2005

WASHINGTON, D.C. - The National Transportation Safety Board recommended today, as a result of the its three-year Supervisory Control and Data Acquisition (SCADA) study focusing on hazardous liquid pipeline systems, that the Pipeline and Hazardous Material Safety Administration require each control center to have policy for the review of alarms. The Board also recommended controller training to include simulator or non-computerized simulations for controller recognition of abnormal operating conditions, in particular, leak events.

In the pipeline industry, SCADA systems collect data from pipeline sensors. Controllers use SCADA to input commands to remotely operate pipeline control equipment including valves and pumps.

In the SCADA study, operators reported that SCADA systems enhanced safety and efficiency of pipeline operations. Furthermore, the study concluded that an effective alarm review/audit system will increase the likelihood of controller appropriately responding to alarms associated with pipeline leaks.

"Last year, there were 141 accidents reported by hazardous liquid pipeline operators releasing over 3.3 million gallons of hazardous liquids, resulting in 5 fatalities, 13 injuries and more than $130 million in damages," said NTSB Acting Chairman Mark V. Rosenker. "The principal issue in the SCADA-related accidents investigated by the Safety Board was the delay in the controller's recognizing a leak and beginning efforts to reduce the effects of the leak."

The Safety Board's recommendations to the Pipeline and Hazardous Material Safety Administration also include:

require operators to install computer-based leak detection systems on pipeline systems unless engineering analysis determines that such a system is not necessary;

require operators of hazardous liquid pipeline to follow the American Petroleum Institute's Recommended Practice 1165 for the use of graphics on SCADA screens; and

change the liquid accident reporting form (PHMSA F 7000-1) and require operators to provide data related to controller fatigue.

A synopsis of the report, including a complete list of the Conclusions and Recommendations, can be found on the Board's website, www.ntsb.gov.


Media Contact:
Terry N. Williams
(202) 314-6100



The National Transportation Safety Board (NTSB) is an independent federal agency charged with determining the probable cause
of transportation accidents, promoting transportation safety, and assisting victims of transportation accidents and their families.