Skip to main content

Noise Control

  • Author:
  • Updated date:

Noise control utilizes techniques used to maintain noise at a level low enough to avoid disturbing people or machinery in the vicinity. Noise is defined as unwanted sound. Noise control is important in any environment occupied by people, such as in industrial plants. It is also important in crowded city streets, dwellings, and offices.

The most direct method of noise control is the reduction of the noise at its source. In industry this control is accomplished by designing machinery with parts that function as quietly as possible and by isolating the working parts from the machine housing so that the housing will not amplify their vibration.

In addition, the housing may include sound-absorbing materials and the entire machine may be placed on a flexible mounting that will reduce vibration transmission to the floor. In offices such machines as typewriters may be cushioned by rubber pads. The noise of city streets is controlled by ordinances prohibiting excessive use of vehicle horns and requiring mufflers that quiet vehicle exhaust noise.

Where reducing the noise output at the source is impractical or insufficient, noise may be absorbed or confined. For example, acoustical tile on a ceiling serves to reduce the propagation of sound. Enclosures or partitions that have sufficient weight will not transmit sound from one area to another. Pipes in a plumbing system can be isolated so that they will not carry vibrations from area to area. Air-conditioning and ventilating ducts may contain both sound~absorbing materials and baffles that will absorb noise along the duct.

Sound-insulating floors, partitions, or enclosures are used to confine the noise within a room or to prevent noise from entering a room. Sound-absorbing materials are used to reduce the noise within the room, and vibration-isolation materials are used to reduce the transmission of vibration to the walls and floors of the room.

Related Articles