Accidental Remote Uploading of PLC Program

Event Year: 2000 Reliability: Confirmed
Country: Canada
Industry Type: Petroleum

A testing and programming facility for the petroleum company’s PLCs was setup by an engineering consultant in a remote city. An engineer who had just returned from the plant site used his laptop to connect to a PLC he believed was in his office. Instead the programming software connected to the last connected PLC, which was a live PLC at the plant site. Not realizing this, the engineer uploaded some trial software to the live PLC causing shutdown of a critical pipeline.


The petroleum company lost approximately 1/2 day of operations and about 10,000 barrels of production.

Action Description: The oil company changed management procedures so that the controls group responsible for operations had knowledge and responsibility for all remote testing and engineering of PLC systems.