This paper reports on noise effects at the ear and the nervous system and on the prevention of noise injuries to man. The antiphones are divided in arrangements to deaden the noise from machines and apparatures in industry, traffic and buildings on one side, on the other side in individual devices for soundisolation. These are application of suitable material on the contacting parts of the human body and above all ear defenders. Different kinds of ear defenders are described. The author points out that the tests for and the selection of workers for noise-factories, considering their auditory vulnerability, are superflue, provided that suitable eardefenders are used. So the military injuries of the car also can be prevented. Eardefenders are of importance to rise the output of work in noisy halls and rooms. They are useful for saving sleep and the nervs. They are consequently of a great social interest and should be subjected to information, propaganda and instructions by law.