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Guidelines in this standard are classified into three levels (see 00.7 Priority and Levels). Emphasis should be placed on conformance Level 1 (L1) guidelines. Software systems that have been validated as complying with all Level 1 guidelines are considered to be L1 Conforming. Software systems can be assessed as L1, L2, or fully conforming depending on the set of guideline to which the system has been validated.
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