Cold shutdown justification

A Cold shutdown justification (CSJ) aka refueling justification (RFJ) means that its appropriate to test a component when the plant is shutdown even though the testing frequency would otherwise require testing when the plant is planned to be at power. Typically associated with IST testing.

IST specifics

ISTC-3520, "Exercising Requirements", Section ISTC-3521 (b) states

"if full-stroke exercising during operation at power is not practicable, it may be limited to part-stroke during operation at power and full-stroke during cold shutdown"

Paragraph ISTC-3521(c) of the ASME OM Code states that,

"if exercising of a valve during operation power is not practicable, it may be limited to full-stroke exercising during cold shutdown."

The staff notes that paragraph ISTC-3521(c) of the ASME OM Code states that exercising "may"-not "shall"-be limited to full-stroke exercising during cold shutdown. Thus, paragraph ISTC-3521(c) does not prevent the partial-stroke testing of the MSIVs at power. (Reference ML18058A523)