The paper describes small scale wind tunnel experiments on the dispersion of contaminants discharged from the bottom of courtyards and other enclosed spaces. The experiments covered a range of courtyards with ratios of depth to width from 5- (consistent with light wells and other very deep cavities) down to 0.1 (consistent with shallow enclosed squares and piazzas that are frequently found in the urban environment).

A method for environmental evaluation of buildings that is general, open ended and based on scientific foundations. Such a method is demanded increasingly, both in Sweden and abroad. This is why the Swedish Council for Building Research is financing both national and international projects in this field.

Each year in Canada, building fires cause hundreds of deaths, thousands of injuries and billions of dollars’ worth of property damage. Canada has the second highest fire death rate among 15 industrialized countries. In Canada in 1988, about 72% of fire deaths and 40 percent of fire property losses occurred in small buildings, such as one- and two-family homes, apartment buildings and hotels/ motels. The 1989 fire statistics for Alberta indicate that about 70% of fire deaths and 51 percent of fire property losses occurred in small buildings.3 What can we learn from these numbers?