Are microwave ovens dangerous

When water is heated on a stove and reaches the boiling point, there are usually the characteristic bubbles that emerge from the bottom of the heated pan. It would be easy, then, to think that all water boils like that when reaching the boiling point. The problem is, that's not always the case.

It is possible to sometimes heat water beyond the boiling point but without the bubbles. Why are there no bubbles? When water reaches the boiling point, the water molecules need to start joining arms with other water molecules in order to create the bubble of vapor that we see as boiling. In order to do that, some molecules need to all meet together at the same place and at the same time at what is called a "nucleation site." A nucleation site can be a tiny impurity, another air bubble, even a scratch on the surface of the container.

Some water is heated in the microwave cooker and both the water and the container are clean enough that there are no nucleation sites. The water temperature goes higher than the boiling point, but without "boiling." Not only that, but because of the way microwaves work, not all of the water in the cup is the same temperature. The water lining the sides of the cup becomes heated, while some of the water toward the interior of the cup is cooler. Should someone then pick up the cup the tiny amount of agitation suddenly creates many nucleation sites throughout the water, triggering sudden boiling and spraying water out of the cup scalding the hand of the person picking up the cup!!!

People with implanted electronic medical devices (e.g. pacemakers) should avoid microwave cookers, as the small amount of microwave leakage may disturb the operation of those devices resulting in potentially serious health consequences.
Only if you break the safety equipment. or run them without a door or with nothing in them.