If a sound is being made that can damage those around it, distracting, or annoying, it is considered noise pollution. If that is the case, applicable measures can be taken to eliminate it. Noise pollution can be harmful to health and productivity in many cases. Harmful and painful consequences of noise pollution include hearing loss, stress, and lack of sleep. The intensity of noise is measured in decibel units and a scale is determined as to which levels are suitable for listening levels for humans. It is common to notice that transportation vehicles and construction equipment produce excessive noise.
Soundproofing materials such as acoustical ceilings, flooring, and foam can help reduce or eliminate noise pollution. Vibration damping and sound barriers are also a common solution to reduce the effects of reverberations as well. Most modern buildings are equipped with sound proofing tools especially in residential and commercial areas. Performance halls, theatres, offices, and schools often have acoustical panels and ceilings to provide noise relief. In industrial settings, acoustic curtains are used to suppress some of the excessive noise created by large machinery for the workers sake.