将建筑物的火灾区域通风到外部可以显著减少烟雾问题，这通常是通过火灾引起的带阻风门的排烟竖井来实现的。一旦发生火灾，各楼层顶部和防火层开口上的挡板将打开，以将烟雾排向外部。任何外来空气都会严重影响排烟竖井的性能。在火灾暴露之前和之后，通过位于非防火楼层上的关闭挡板进行了泄漏测试，以测量目前用于烟井应用的业主防火挡板的空气泄漏特性。 火灾前泄漏面积与风门面积的试验比率通常低于21%。暴露于标准时间温度后，比率通常低于4%。将炉子最高温度限制在1000华氏度（540摄氏度）可显著降低因火灾导致的泄漏面积比增加。引文:研讨会论文，佐治亚州亚特兰大，1984年

Venting the fire region of a building to the exterior significantly reduces smoke problems This is often achieved by means of a smoke exhaust shaft with dampered caused by a fire. In the event of fire, the dampers at the top and on the fire floor openings on each floor are opened to exhaust smoke to the exterior.The performance of the smoke exhaust shaft is seriously affected by any extraneous air. Tests have been conducted leakage through closed dampers located on the non-fire floors before and after fire exposure to measure the air leakage characteristic of proprietory fire dampers currently used for smoke shaft application.The pre-fire test ratios of leakage area to damper area were generally below 21 percent. After exposure to the standard time-temperature, the ratios were generally below 4%. Restricting the maximum furnace temperature to 1000°F (540°C) considerably reduced the increase in leakage area ratio due to fire exposure.