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Interpretation 90.1-2019-1 - June 1, 2020 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section 6 and Table 6.8.1-16, regarding minimum efficiency requirements for heat pump and heat recovery chiller packages.)
Interpretation 90.1-2019-2 - June 1, 2020 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section 6 and Table 6.8.1-16, regarding minimum efficiency requirements for heat pump and heat recovery chiller packages.)
Interpretation 90.1-2019-3 - June 5, 2020 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section G3.1.3.7, regarding Appendix G type and number of baseline chillers.)
Interpretation 90.1-2019-4 - June 5, 2020 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Tables 9.4.2-2 and G3.6, regarding Appendix G baseline building exterior lighting.)
Interpretation 90.1-2019-5 - March 31, 2021 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Sections 6.5.3.5 and 6.5.3.5.1, regarding supply air temperature reset.)
Interpretation 90.1-2019-6 - June 9, 2021 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section 6.5.2, regarding the application of Section 6.5.2 to hospital zones.)
Interpretation 90.1-2019-7 - October 13, 2021 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section 5.5.4.1, regarding the determination of WWR for use with Tables 5.5-0 to 5.5-8.)
Interpretation 90.1-2019-8 - October 13, 2021 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Table G3.1 #5, Baseline Building Performance column, item (c), regarding Appendix G baseline fenestration modeling requirements.)
Interpretation 90.1-2019-9 - February 6, 2023 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section 3, regarding the definition of a conditioned space – cooled space.)
Interpretation 90.1-2019-10 - February 6, 2023 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019 Appendix G requirements applicable to computer rooms.)
Interpretation 90.1-2019-11 – June 24, 2023 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section G3.1.2.5 Exception1, Baseline Building Performance column, item (c), regarding calculation of the average design capacity.)
Interpretation 90.1-2019-12 – June 26, 2023 (Refers to ANSI/ASHRAE/IES Standard 90.1-2019 Section 3 definition of indirectly conditioned spaces.)
Interpretation 90.1-2019-13 – October 7, 2023 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section 5.4.1, regarding insulation and Section 11.2(a) and Appendix G, G1.2.1(a).)
Interpretation 90.1-2019-14 – January 30, 2024 (Refers to the requirements presented only in ANSI/ASHRAE/IES Standard 90.1-2019, Section 3.2, 4.1.2, 4.2.1.3, and 5.1.3, regarding roof replacement.)
Interpretation 90.1-2019-15 – January 30, 2024 (Refers to the requirements presented in ANSI/ASHRAE/IES Standard 90.1-2019, Section G3.1.2.6 Exception 2, regarding determining if the proposed design includes an economizer.)