The new crown antigen test should not take more than 30 minutes, as the reading may not be valid if it takes too long. At present, the best time for antigen detection is 15 minutes, and the data readings are more accurate around 15 minutes. If the data are observed after a 30-minute interval, it may result in a failure of the test results, and such data cannot be used as a basis for testing. In the antigen test, you need to observe the C first, if the C appears red or purple, it belongs to the valid area; and then observe the T, if the two lines are darker and lighter or the two lines are darker, it suggests that it is positive. If the test result is found to be positive during the antigen test, it is necessary to report to the community or hospital immediately, complete the nucleic acid test in time, isolation and treatment, and must not be handled privately, so as not to cause adverse effects.