EN 15284:2007 – Materials and articles in contact with food stuffs – Test method for the resistance to microwave heating of ceramic, glass, glass- ceramic or plastics cookware

1 Scope
This European Standard specifies a method for the determination of the resistance to microwave heating of cookware made of ceramic, glass, glass-ceramic or plastics. It is applicable to articles that are intended for multiple re-use in a microwave oven. It is not applicable to articles, particularly those made from plastics, which are intended to be discarded after one use.
2 Principle
An article is subjected to microwaves in the presence of water external to the test specimen for both a short and a long period of time, and any damage to the article is noted. For articles with handles, the temperature of the handle is measured after the short period of heating. The maximum surface temperature can be determined after the short and long periods of heating in order to provide additional information for manufacturers and suppliers.
3 Apparatus
3.1 Microwave oven, fitted with a turntable, capable of an output of at least 600 W (as determined in 5.1).
3.2 Surface temperature measuring apparatus, comprising an electrical thermometer with a contact sensor made of metal and having insignificant heat capacity (instrument accuracy shall be at least ± 1 °C).
3.3 Two water containers small enough to fit into the rear corners of the oven, each capable of containing 125 ml of water.
3.4 Stopwatch, capable of measuring to an accuracy of ± 1 s.
4 Test specimens At least three identical test specimens of each type (representing the range of shapes and functions of the set of cookware or tableware being examined) shall be tested. Where there are articles made from different materials in the set, three test pieces representing each material shall be taken.
5 Calibration of microwave oven 5.1 Determination of power output In order to protect the magnetron during the procedure (Clause 6) it is necessary to provide ballast in the form of 250 ml of water (6.4) in two containers (3.3). Therefore, also include this ballast during calibration but ignore it for the purpose of the calculation (5.2). Make the measurement with a water load in a glass container. The water and container temperature shall initially be below ambient temperature and be raised to an equal temperature above ambient. This procedure ensures that any heat gains or losses from the surroundings have a minimum effect.
A cylindrical container of borosilicate glass shall be used for the test. It shall have a maximum thickness of 3 mm, an external diameter of approximately 190 mm and a height of approximately 90 mm. The mass of the container shall be determined.
EN 15284:2007 – Materials and articles in contact with food stuffs – Test method for the resistance to microwave heating of ceramic, glass, glass- ceramic or plastics cookware