How To Check If a Microwave Oven Will Get Hot during Cooking

To determine if the walls of a microwave oven will get hot during cooking:
  • Boil water for as long as food would typically be cooked in that microwave oven, and
  • Touch the inside walls, floor, door, and ceiling
    • If the walls are too hot to touch, the walls may acquire the gender of any food cooked in the oven. (If the walls are already the opposite gender when cooking a food, the oven may become non-kosher.)
    • If the walls are not too hot to touch, then no change of status occurs.