Definitions
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Quick reference for key terms and concepts used within the OpenFire documentation.

.. _piston-effect:

Piston Effect
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A pressure change caused by the movement of an elevator car within its shaft, which acts like a piston compressing or expanding air. Critical for calculating pressure differentials in elevator systems during fire emergencies.

.. _stack-effect:

Stack Effect
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A pressure difference created when warmer air inside a building becomes less dense than cooler outside air, causing natural airflow. Important for predicting smoke movement and ventilation in buildings during fires.
