There is no arguing that microwave ovens are one of the most common appliances in kitchens around the world. Despite the negative connotations that come along with the idea of “nuking” your food, they have come to be regarded as an essential tool due to their convenience.
There are debates about health concerns associated with cooking in a microwave, but are they even safe to be around?
Is it safe to use a microwave with a hole or crack? The simple answer is that it depends on the size of the hole or crack, but in reality, there is little risk of being around a microwave that is running. This applies to microwaves with a hole or cracks, as well as those that are in perfect condition—the science of how microwaves work will help you feel more at ease about using your microwave.
Microwaves became popular because they cook food so much faster than a conventional oven. But it wouldn’t matter how fast you could reheat a slice of pizza if the oven you did it in makes you sick in the process. Microwaves have been common in modern kitchens for more than a generation.
If they weren’t safe, we would know by now. This article will explain why microwaves are safe – with or without cracks or holes.
Why Is It Safe to Use A Microwave Oven?
In order to understand why microwave ovens are safe, you need to understand how they work and what features contribute to their safe operation. Once you do, you’ll understand what size hole or crack would allow microwaves to escape from the oven. Of course, even if microwaves were to escape from the oven—science helps to explain why there is little risk to people in the same room as the oven.
How A Microwave Oven Works
A microwave oven heats food by exciting water molecules inside the food. The movement of the molecules causes friction, which generates heat. So how does the electricity behind one of the wall outlets in your home become a steaming hot food or beverage when the microwave oven dings or beeps?
Electricity
Electricity is the source of energy that ends up being converted to heat. Fundamental physics tells us that a change in the physical state of matter requires the influence of an external influence. In this case, electrical power is being converted to non-ionizing radiation that is aimed at your food.
Magnetron
The Magnetron is the element in your microwave oven that does the job of converting electrical energy to non-ionizing radiation. The fact that it is non-ionizing radiation is important to note because that’s one of the main reasons that microwave ovens are safe to be around while exposure to ionizing radiation like we find in X-ray machines is strictly limited.
Waveguide
The waveguide runs from the magnetron to the stirrer and into the cooking cavity of your microwave oven. Basically, it is a tunnel that makes sure all of the energy that has been converted gets directed to the job that it is being used to do. That’s what makes microwave ovens so efficient.
Stirrer
The stirrer is a fan that scrambles the microwaves as they exit the waveguide and enter the cooking chamber. The heating process that warms your food relies on microwaves bouncing off of the insides of the cooking chamber and colliding with one another. This works better when they get scrambled so that they are coming and going in different directions.
Cooking Cavity
The cooking cavity is the area where you place your food. While a conventional oven works by using gas, electric, or convection technology to heat up the space, a microwave’s cooking chamber is just a place for microwaves to bounce around.
That’s why you don’t get burned if you touch the inside of a microwave oven right after cooking something. You wouldn’t want to try the same thing after cooking a frozen pizza in your conventional oven at 400°F for 20 minutes.
Door & Choke
Most microwave ovens won’t begin to operate if the door is open. Many people think that this is a safety feature to make sure that no microwaves leak out and radiate the room and the people in it. It’s actually a feature that is as much about efficiency as it is about safety.
If the microwaves leave the closed cooking cavity, then they don’t excite the water molecules in your food. That would be an inefficient way to heat things up.
It wouldn’t be a good idea to remove the door of your microwave oven, disable the choke, and then stand with your body blocking the opening.
That isn’t because you would start to glow. It’s because you would get cooked—and by that, we mean burned. If “you” are the matter with a high water content that absorbs the microwaves, you will be the item that gets heated up to the boiling point.
In the next section, we’ll talk more about how the physical properties of microwaves determine what is and isn’t safe to do with microwave ovens.
Why Are Microwave Ovens Safe?
The first thing that you need to know about microwave ovens is that the microwaves that they use to heat food aren’t dangerous to people in the first place. Once you understand that, you can understand why a small crack or hole in your microwave isn’t a safety concern.
Screens: Many microwave ovens have a visible metal screen that is either inside of the glass window in the door or in between panes of glass in the window. The metal screen is a fine mesh, but the size of the holes in the mesh varies from one manufacturer to another. What you might not realize is that most microwave ovens have a layer of this mesh running within the walls of the cooking cavity to keep microwaves from escaping anywhere.
If the screen is intact, you could remove the glass from the door or one of the walls from the exterior of the microwave without making it any less safe. The mesh is the feature that does the work of keeping the microwaves inside the cavity.
Wavelengths: All electromagnetic energy travels in waves, and they are called waves for a reason. They have peaks and troughs that are constant and measurable. That’s how we know that the “size” or wavelength of microwave energy is 12 centimeters (roughly 4.7 inches). Since we know that microwaves have a big wavelength, we know that they can’t leak out of or squeeze through the holes in the mesh of the screens that are inside your microwave.
Holes and Cracks: But what if your microwave has a hole or crack in the mesh of the screen? Because you know that microwaves have a wavelength of more than 4 inches, you know that a hole or crack in your microwave that is smaller than 4 inches is going to be too small to allow microwaves to escape.
But what if the hole is larger and microwaves do escape? Remember that microwaves are non-ionizing radiation. That means that they don’t carry a lot of energy as individual waves. They do their work by getting excited in a big group. If they leak out of the microwave and into a wide-open area like your kitchen, they will dissipate rapidly.
Conclusion
Know you know how microwaves work and why you shouldn’t be afraid to use one that has a small hole or crack. While you might want to replace an aging microwave for aesthetic reasons or to get a more energy-efficient model, you won’t have to worry about your old one making you sick while you’re shopping for the right one.
Sources:
https://www.hunker.com/13418901/what-causes-the-inside-of-a-microwave-to-crack