Air lock

Air lock is a device that permits the passage of people and objects between a pressure vessel and its surroundings while minimizing the change of pressure in the vessel and loss of air from it. The lock consists of a small chamber with two airtight doors in series which do not open simultaneously.

An air lock has three main uses. Firstly, it helps maintain the environment's pressure within the vessel. This is crucial in space or underwater applications where pressure is different than the surrounding environment. Secondly, it prevents the escape of atmosphere from the vessel. Lastly, it also prevents the entry of a hazardous atmosphere into the vessel.

Design and Operation

The design of an air lock depends on the pressure, the desired functionality, and the size of the objects to be transferred. The operation of an air lock begins with the opening of one door of the lock to allow the object or person to enter. After the door is sealed, the pressure within the air lock is gradually equalized with that of the target environment. Once the pressures are equal, the second door opens to allow exit.

Applications

Air locks are used in a variety of applications. They are commonly found in spacecraft, submarines, diving chambers, and hyperbaric chambers. In these applications, the air lock is used to maintain the internal pressure while allowing movement between environments.

In biology and chemistry, air locks are used in laboratories to maintain a sterile or controlled environment. They are also used in cleanrooms in the semiconductor industry to prevent contamination.

Safety Considerations

Safety is a critical aspect of air lock design and operation. The pressure difference between the environments can pose a risk of decompression sickness or barotrauma. Therefore, the pressure equalization process must be controlled and monitored carefully.

See Also

• Decompression (diving)
• Hyperbaric medicine
• Spacecraft