The noise barriers we make are a natural or artificial obstacle placed on the path between the noise source and the observation point. Behind the obstacle, an area of reduced sound intensity is created, called an acoustic shadow. The screens owe their usefulness to two basic physical parameters, i.e. acoustic insulation and sound absorption coefficient. The first one is responsible for the amount of acoustic energy that will pass through the screen itself to the area it protects, and the second one is responsible for the amount of energy of the sound wave that will be reflected back towards the sound source. In order for the effectiveness of acoustic screens to be high, both parameters should be as high as possible, i.e. the amount of energy of the acoustic wave reflected and passing through the screen layer should be as low as possible. When designing the screen, we take into account not only its dimensions, but also its location in relation to the noise source. An important issue is also the material from which the screen is made and the structure of its surface, limiting sound reflections.