| 摘要 |
A smoke release and ventilation window comprises a window frame 12 housing upper and lower window members 10, 11 each slidable in the frame 12 between a normally closed position and an upper position, the upper window member 10 being retained in its upper position by electrical means, preferably an electromagnet 20, the arrangement being such that, on de-energising of the electrical means 20 in response to a smoke detector or heat sensor, the upper window member 10, falls under gravity to its open position, and, consequential upon said fall of the upper window member 10, the lower window member 11 is raised to its open position, thereby providing gaps above and below the window members 10, 11 and through which smoke can escape. |
