1、Page 1 of 2 2015 ASHRAE. All Rights reserved. Interpretation IC 170-2013-6 of ANSI/ASHRAE/ASHE Standard 170-2013 Ventilation of Health Care Facilities Date Approved: June 30, 2015 Request from: Travis English, Kaiser Permanente, 1800 Harrision Street, Oakland, CA 94612. Reference: This request for i
2、nterpretation refers to the requirements in ANSI/ASHRAE/ASHE Standard 170-2013, Section 7.1.a.6.ii, regarding use of the multiple space calculation method. Background: Standard 170-2013 7.1.a.6.ii indicates designers may use “the Ventilation Rate Procedure (multiple zone formula) of ASHRAE Standard
3、62.1” (S62). And, in doing so, “The minimum outdoor air change rate listed in this standard shall be interpreted as Voz (zone outdoor airflow) for purposes of this calculation.” Thus, V170 = Voz Where V170is the per space outdoor air flow derived from air change rate. In ASHRAE Standard 62.1, Vozis
4、composed of an area-based component, (Ra Az), and an occupant based component, (Rp Pz). In order to calculate the uncorrected outdoor air intake, Vou, in S62 Equation 6-6, it is necessary to separate Vozinto these two components. Equation 6-6 reads: Vou= Dall zones(Ra Az)+ all zones(Rp Pz)Where D is
5、 the occupant diversity, defined by S62 Equation 6-7, which reads: D = Ps /all zonesPzTo successfully complete the calculation, the following is proposed: 1. Assume a relatively high value of Rato ensuring that each area receives minimum ventilation. Ra= 0.12 is here proposed, which is equal to the
6、Rain S62 used for spaces such as break rooms, photo studios, libraries, childrens museums, etc. See S62, Table 6-1. 2. Substitute V170 into S62 Equation 6-6, using Ra= 0.12. S62 Equation 6-6 is currently written as: Vou= D allzones(Rp Pz) + allzones(Ra Az) It would be re-written as follows Vou= D al
7、lzonesV170- Ra Az + allzones(Ra Az) Which, using Ra=0.12, simplifies to the following: Interpretation IC 170-2013-6 Page 2 of 2 2015 ASHRAE. All Rights reserved. Classified - Internal use Vou = D allzonesV170+ (1-D)allzones0.12 AzUsing this, the remaining calculations in S62 Equations 6-6 through 6-8, may be completed. Interpretation: Is it acceptable to assume a value of Rafor the calculation of Vou(S62, Equation 6-6). Question: Is this interpretation correct? Answer: Yes. Comments: Values for Rp and Ra have not yet been identified for health care spaces.
