Class O facilities are nonprotected outlets and are subject to prolonged outages which may go undetected and unreported.

With extensive shutdowns like these, how would Lilco provide electricity if Shoreham experiences such a prolonged outage?

Its Palo Verde Nuclear Generating Station in Arizona, the largest nuclear plant in the U.S., came under scrutiny by the Nuclear Regulatory Commission in 2005 when operational problems began to cause prolonged outages.

Reddit, Foursquare, and Quora were among the many sites that went down recently due to a prolonged outage of Amazon's cloud services.

This caused numerous, prolonged outages.

Their memorandum cited "excessive and prolonged outages" in a radar system that helps air traffic controllers keep track of planes on the runways.

SDG&E implemented their system restoration plan and cautioned its customers to expect a prolonged outage.

Upon petition of the owner or operator of any unit, the Administrator may make appropriate baseline adjustments for accidents that caused prolonged outages.