As a fundamental study to standardize the methyl violet paper (MV) test, which is used to test the stability of nitric acid esters, in a domestic industrial standard, we investigated the influence of differences in the test conditions on the evaluation results of the MV test. Based on the results, which showed that the stability varies with the heating temperature of the sample, the heating method, and the types of test paper (MTC/NDS), we discussed suitable conditions and procedures for the MV test. Aiming to propose a safer technique for evaluating stability, we conducted small-scale NOx measurements using a detection tube. The results showed that small-scale NOx measurements could be used to predict the results of the MV test. We propose a stability evaluation flow using the small-scale NOx measurement test.