Refers top the design of an athletic fieldhouse in Regina, Saskatchewan in 1985 to accommodate the indoor field portion of the 1987 Western Canada Summer Games. Describes how the difference between the design requirements and nominal anticipated utilisation opened the way for integration of a carbon dioxide detection system to assist in controlling the minimum outdoor air requirement. Traces the history of the installation from conceptualisation to an indication of the success of the concept in a practical application.

KEYWORDS: Canada, designing, controls, indoor, air quality, carbon dioxide, ventilation, outdoor air, stadia, sensors, monitoring, case studies.