A number of tests of the Memorial Fire Ventilation Test Program were devoted to determining the effectiveness of a full-transverse ventilation system in limiting the spread of smoke and hot gases, with varying system configurations and airflow rates. The controlled fire, located at the approximate quarter point of the 2,800 ft (854 m) Jong tunnel was varied in three levels of intensity: 10, 20, and 50 megawatts (MW).

Most modern office blocks in Southern Africa are air conditioned, for obvious reasons, but some developers are eager to find ways of reducing the capital cost of these projects. Fred Smith of Ove Arup Partnership reports on one· particularly innovative project in Zimbabwe where passive cooling ·met the brief.

Air conditioning may have economic and health disadvantages, but it does provide protection against future change in functional requirements of buildings, says Professor Patrick O'Sullivan. It will continue to be essential in high density urban areas, but there will be many cases where there is no clear distinction as to the which mode of environmental control, natural or  mechanical, should be adopted