Final answer:
An adjustable gas nozzle, which is a type of entrainment device, is used to control the flow of gas to tables in the dining area by creating low pressure to entrain air for proper combustion.
Step-by-step explanation:
The method used to control the flow of gas to tables in the dining area is known as an adjustable gas nozzle, which is an example of an entrainment device. These devices use increased fluid speed to create low pressures, which then entrain one fluid into another. In the case of a Bunsen burner, an adjustable gas nozzle entrains air for proper combustion. This principle can be applied in various settings, including dining areas to control the flow of natural gas for cooking or heating applications. Such control is essential for maintaining safety and efficiency in the use of natural gas for consumer-end applications.