The technology of noise control both inside and outside buildings is well developed today. The problem is that it is too seldom used.It s a noisy world. Twenty-four hours a day, seven days a week, we are exposed to sounds we do not want, need, or benefit from. There are few places on the planet where in our daily lives we are free from unwanted sounds.Noise from many outdoor sources assails our hearing as it invades our homes and work places: traffic, aircraft, barking dogs, neighbors voices. Noise within the workplace from office machines, telephones, ventilating systems, unwanted conversation in the next cubicle distracts us from our work and makes us less productive.Noise from within the home from appliances, upstairs footsteps, TV sound traveling from room to room keeps our homes from being the restful refuges they ought to be. Noise in the classroom impedes the learning process and threatens our children s educational experience.Noise can frustrate and impede speech communication. It can imperil us as we walk or drive city streets. It can be a physical health hazard as well: exposure to high noise levels can cause permanent hearing loss.In short: Noise is unwanted sound. There are solutions.We don t need to suffer the distracting, fatiguing, and unhealthful consequences of noise. There are practical and economical solutions to almost all noise problems in the built environment. To approach the solution to any specific noise problem, we need to:Understand the basic physics of acoustics and how noise unwanted sound is produced, how it propagates, and how it is controlled.Learn the basics of noise control, and how to approach the problem from three standpoints: the source of noise, the path it travels, and the point of reception.