The disadvantage of previous traffic noise barriers is in their location at a relatively big distance from the source of noise, which forces to build tall structures which hinder visibility thus making inconvenience to the travellers, not to speak about the inhabitants behind the barrier.

The building and maintenance costs of traditional tall noise barriers are hig h and due to sound reflection they can have undesirable side effects, besides being unsuitable for use, e. g. on road and railway bridges.

Figure 1 shows in a vertical section parallel to the road how the noise reduction barrier is fixed to a conventional road safety barrier. Number 1 indicates the noise barrier device, number 1a indicates the noise suppressing element of the device. Number 2 indicates the fixing device used to attach the noise barrier 1 to the safety barrier's horizontal beam 5 either directly or with the aid of a horizontal spacer beam 3. Number 4 indicates the vertical post of the safety barrier.

Figure 2 shows in a vertical section parallel to the bridge, how the noise barrier is fixed to a road or railway bridge parapet. The horizontal beam i s number 5 and the vertical post is number 4.

Figure 3 shows, how the noise barrier is fixed to a conventional road safety barrier in the direction of the road. In the drawing the noise suppressing element 1a is shown as transparent and behind it are visible the horizontal beam 5 and vertical post 4.

Figure 4 also shows how the noise barrier is fixed to a conventional road safety barrier in the direction of the road. Here the noise barrier 1 is fixed directly to the horizontal beam 5 with its fixing devices 2.

The method and device for suppressing the traffic noise, according to the patent claims, the noise barrier 1 is fixed to the road safety structures 4 and 5 with its fixing device 2. The noise suppression element 1a should be tilted to suppress sound reflections. The structure of the noise barrier 1 consisting of separate interlocking suppressing elements 1a gives the suppressing elements 1a possibility to settle according to unevennesses of the roadside, making it unnecessary to level existing terrain and at the same time ensuring that road maintenance access is not hindered. The noise barrier 1 is excellently suited for use on road and railway bridges due to its light and low structure.

Depending on the properties of noise suppressing element 1a, it can be stiffened vertically either with a plate like or beam like structure (not shown).

Where no road barrier exists the device 1 can be installed using a separate stand (not shown) in the immediate vicinity of the road.