英文水平差，没理解EN71-3：2019第9点：迁移溶液的稳定与分析里面的9.3六价铬的第一句（Neutralize the migration solution (see 8.3, migration procedure) according to F.4 without delay. After neutralization the solution is stable for at least 4 h），  到底是至少稳定4小时再测试还是该溶液至少可以稳定4小时；有高人指点一下吗