The new crown test paper is also known as the new crown antigen test reagent, two bars after the timeout is the reagent is placed for too long, the reagent card through the air oxidation of the results have changed. The new crown antigen test reagent should first understand the correct method before use, after use in the effective time to observe the results, the C area, T area all appear results, indicates that the antigen test is positive, only the C area results, and the T area does not appear the results, indicates that the test is negative, through the positive or negative to determine the organism whether there is a possibility of infection with the new coronavirus. New crown antigen test reagent timeout after the observation of two bars, this result is not certain that it is positive, to be considered false positive, is the reagent in the air for too long, after oxidation to change the results of the reagent, and can not be used as a basis for diagnosis. There are new crown antigen test reagent two bars after timeout, there are doubts about this result, it is recommended to go to the regular hospital through the relevant examination to determine whether there is infection of new coronavirus, during the period of good protection and isolation measures to avoid adverse consequences.