Damper (flow) Opposed blade dampers in a mixing duct. A damper is a valve or plate that stops or regulates the flow of air inside a duct, chimney, VAV box, air handler, or other air-handling equipment. A damper may be used to cut off central air conditioning to an unused room, or to regulate it for room-by-room temperature and climate control. Its operation can be manual or automatic. Manual dampers are turned by a handle on the outside of a duct. Automatic dampers are used to regulate airflow constantly and are operated by electric or pneumatic mo
The main function of the immune system is defense against microbial infection. The other major functions of the immune system depend on a number of major actions that defend us against threats to our health.These actions help our immune system sort out a system of complicated reactions that our body uses every day to defend us from infection and disease.he other major functions of the immune system depend on a number of major actions that defend us against threats to our health. These actions help our immune system sort out a system of complicated reactions that our body uses every day to defend us from infection and disease.
One of the main tools in the arsenal of our immune system is a group of specialized cells known as lymphocytes. Lymphocytes are a type of white blood cell that function as part of the immune system. Their various functions allow them to properly respond to foreign invaders in the body.