described is an element analysis device , which can be used to obtain precise measurements even under unfavorable environmental conditions . for this , the device is provided with a transporting means with a measuring region for transporting the substance to be measured , an excitation source with an exit window located in a first case and an x - ray fluorescence detector that is directed toward the measuring region , as well as an entrance window that is located in a second case . to minimize the air absorption and prevent dust and dirt from being deposited , a tube extends from the entrance window and / or the exit window in the direction of the measuring region , which tube is essentially tightly connected to the respective case and is open at the end facing the measuring region and is provided with a connection for feeding a flushing gas into the tube .