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Interpretation 90.1-1999-1 - February 4, 2000 (Ref. Section 9.3.2, relating to the exterior
lighting power allowance)
Interpretation 90.1-1999-2 - February 6, 2000 (Ref. Section 6.2.1, relating to the efficiency requirements for HVAC equipment)
Interpretation 90.1-1999-3 - February 6, 2000 (Ref. water heater requirements in Section 7.2.2 and Table 7.2.2)
Interpretation 90.1-1999-4 - February 6, 2000 (Ref. to the requirements presented in ASHRAE/IESNA Standard 90.1-1999, Section 9.3.1.2, Additional Interior Lighting Power.)
Interpretation 90.1-1999-5 - February 7, 2000 (Ref. Section 4.1.2.1, Additions to Existing Buildings, and Section 4.1.2.2, Alterations to Existing Buildings
Interpretation 90.1-1999-6 - February 6, 2000 (Ref. Section 11.4.2, Building Envelope (Energy Cost Budget Method)
Interpretation 90.1-1999-7 - June 25, 2001 (Ref. Section Section 5.2.3.4, Vestibules)
Interpretation 90.1-1999-8 - January 25, 2004 (Ref. the requirements presented in ANSI/ASHRAE/IESNA Standard 90.1-1999, Section 3.2 Definitions and Section 6.3.3 Air System Design and Control, specifically relating to the definition of fan system energy demand (or fan system power))