Abstract
A miniaturized earborne sound level duration time meter is described which utilizes photographic film as the storage element. It measures the time during which the sound pressure has exceeded two preset levels. In addition it records the running time of the device. The running time can be preset to either one day or one week. The microphone is placed at the entrance of the ear to measure just the sound that might damage the ear. It has been possible to make the meter so small that it can be worn under ear muffs. The weight of the complete device is 15 gram.