The test containers used are 1 l bowls with odor-neutral sealing and covers. For example, bowls by Leifheit, model “Einkochspa?”, which are available in housewares stores, can be used. The 1 l bowl was selected for ease in testing. For repeat measurements (section 4.4.1, f), 3 l bowls are recommended. The test containers must be washed prior to each test sequence (e.g., with a laboratory glassware washer) and must be clean and odor-neutral.