One of the ventilation approaches tested to determine its effectiveness in limiting the spread of smoke and hot gases in a tunnel was the partial transverse system. A single-zone partial transverse system was tested with both supply and exhaust ventilation. A two-zone system was tested with exhaust in the fire zone and supply in the adjacent zone. Thirty-two tests were conducted with fire sizes of 20, 50, and 100 MW. Addresses results of these tests and conclusions drawn from these results. An eyewitness account of some of these tests by the author is included.

Units: Dual

KEYWORDS: year 1997, Testing, smoke ventilation, tunnels, USA, fire, air change rate, roads