目前设计排气管高度和出口速度的方法是基于避免污染烟囱所在建筑物的屋顶、墙壁和附近地面。通常情况下，不考虑相邻建筑物的影响，如果它们位于上风，则会增加湍流和扩散，如果它们位于排放建筑物的下风，则可能会受到污染。ASHRAE研究项目897针对两种侧风宽度，对16个相邻和排放建筑配置进行了系统研究，以确定实验室烟囱设计中应如何考虑相邻建筑。该研究项目有四个不同的目标:使用排放和相邻建筑对的比例模型，在广泛的变量范围内建立相邻建筑影响的目录。使用本建筑物稀释测量目录的结果来推荐烟囱设计程序。 使用计算机模型ISC3和SCREEN3以及其他分散模型将测量稀释度与分散度计算进行比较。准备对现有模型适用性的评论。

Current methods for designing exhaust stack height and exit velocity are based on avoiding contamination of the roof, walls and nearby ground surface of the building on which the stack is located. Usually, no account is taken of the effect of adjacent buildings that add turbulence and increase dispersion if they are located upwind, and may be contaminated themselves if they are downwind of the emitting building. ASHRAE Research Project 897 carried out a systematic study of 16 adjacent and emitting building configurations for two crosswind widths to determine how adjacent buildings should be accounted for in laboratory stack design. The research project had four distinct objectives:to use scale models of emitting and adjacent building pairs to build a catalogue of the effect of adjacent buildings over a wide range of variables.to use the results of this catalogue of building dilution measurements to recommend stack design procedures.to compare measured dilutions with dispersion calculations using the computer models ISC3 and SCREEN3 and otherdispersion models.to prepare a commentary on the suitability of existing models.