ASHRAE标准62.1–2004:可接受室内空气质量的通风包含多个空间方程式的一般形式，其中包括考虑通过二次空气路径输送的空气，如风扇供电箱或换气风扇。多空间方程描述了循环系统中未启动通风空气的循环。这个方程有一个变量，呃，它描述了二次空气来自相关区域的程度，而不是来自“平均系统回风”。Erhad没有被测量，因此该标准无法为用户提供关于使用什么值的准确指导。RP-1276的目标之一是测量一栋典型建筑中的Erin值。第二个目标是通过实验确定多空间方程是否有效。在奥马哈的一栋建筑上进行了示踪气体实验，以研究ERAN并验证多空间方程。 对二者的研究表明，它的理论范围是从零到无穷大。其在测试建筑中的范围为0.74至1.01，但如果风扇供电箱位于不同但实际的位置，其范围可能为0.13至1.15。这些结果与标准相矛盾，该标准描述的电子逆向拍卖的范围为0到1。对多空间方程的实验验证表明，该方法是有效的。这一结果的推论是，在典型建筑中，不能依靠被动分区间混合来满足标准62.1–2004的通风要求。

ASHRAE Standard 62.1 – 2004:Ventilation for Acceptable Indoor Air Qualitycontains a generalized form of the Multiple Spaces Equation that includes consideration of air delivered through secondary air paths such as fan-powered boxes or transfer air fans. The Multiple Spaces Equation describes the recycling of unvitiated ventilation air in a recirculating system. This equation has a variable, Er, that describes the extent to which the secondary air comes from the zone in question, as opposed to coming from “average system return air”. Erhad not been measured, so the standard was unable to provide users with exact guidance about what values to use. One of the objectives of RP-1276 was to measure values of Erin a typical building. A second objective was to experimentally determine whether the Multiple Spaces Equation is valid. Tracer gas experiments were carried out on a building in Omaha to study Erand to validate the Multiple Spaces Equation. The study of Ershowed that its theoretical range is from zero to infinity. Its range in the test building is from 0.74 to 1.01 as built, but could range from 0.13 to 1.15 if the fan-powered boxes were located in different, but realistic locations. These results contradict the standard, which describes Eras having a range from 0 to 1. The experimental validation of the Multiple Spaces Equation shows that it is valid. The corollary to this result is that passive interzonal mixing can not be relied upon to satisfy the ventilation requirements of Standard 62.1 – 2004 in a typical building.