What Causes Hole In Microwave?

My three-year-old microwave oven has a rusty hole in the roof. I just realized it is an issue that often happens with these gadgets. But I need to get to the bottom of what causes a hole in a microwave.

If your microwave has a hole, it results from stubborn stains, age, moisture, and design. Any perforations not part of your microwave’s design are dangerous to your health, especially if rusty. However, you shouldn’t worry about a small non-rusty hole or a crack less than 4 inches wide. It won’t release microwaves into your kitchen. 

Holes/cracks that are rusty pose a danger of contamination and radiation. The rusts and waves are dangerous to your body’s processes as you could expose yourself to burns, glaucoma, and infertility. Don’t go as this guide enlightens you on holes in microwave ovens

How To Fix Hole In Microwave?

It is way too dangerous to operate a microwave with a hole. So, you need to know what to do if you spot one that didn’t come with the oven. 

You cannot patch a hole in your microwave. I recommend replacing your microwave if you spot a hole (apart from the ones that come with the oven). If you are unsure if the gap is part of the microwave design, don’t hesitate to get in touch with the manufacturer. They will clarify their design and what’s not normal for the oven.

Again, the hole you spotted may be larger than usual, which should cause worry. Such a hole can release microwaves from the cooking chamber. Though the waves are high and powerful, they are not strong enough to cause cancer. But they can burn your skin and damage your eyes. So, an unusual hole in your oven is a health hazard. Beware of dangerous radiation from the oven, especially if the spot is more than 4 inches.

Also, do not attempt to seal a hole in your microwave. It could be a design flaw, so feel free to make that important call to the customer service department. Otherwise, a small hole shouldn’t worry you. Neither should the perforations that come with your Microwave. The oven comes with safe designs that guard users against harmful radiation. 

Rusty Patches on your microwave

It could be a rusty patch and not a hole! Examine your microwave, especially on the roof. You will be surprised that it is minor chips on the surface. Rusty patches can give you food poisoning. Also, the peeling paint isn’t good for your health. 

There is hope as you do not have to throw away the oven. You can ask your repair clinic to fix them or do it yourself. Have a look;

Steps to fixing rusty patches in your microwave;

You need microwave cavity paint and masking tape. You can order from your microwave dealer or ask for recommendations from your repair center.

Step one:

Unplug your oven from the outlet.

Step two:

Empty your oven, including the turntable.

Step two:

Close the door. If the rusty sports are on the roof of your oven, turn your oven upside down.

Step three:

Use a blunt knife to remove the peeling and paint chips. Scrap with sandpaper to ensure that the surface is smooth.

Step four: 

Wipe clean and wait to dry. 

Step five:

Use masking tape to seal the microwave holes on the interior surface. These are unique to the microwave design. The holes are well-spaced, allowing long microwaves to bounce inside the cooking chamber. Seal them to prevent paint from blocking them.

Step six:

Spray the first coat all over the interior surface. Give the coating some time to dry before repeating the second coat. Alternatively, you can do touch-ups on the patches with rusty spots. 

Step seven:

Allow your microwave to dry for 24 hours before cooking. Note that you can follow the microwave cavity paint specifications for the drying period.

Is It Dangerous To Have A Hole In Your Microwave?

If your microwave has a hole in the interior, you may worry if the electromagnetic radiation will behave normally or if it will escape into your kitchen and harm you. Before you get the answer to this nagging question, you need to establish the size of the hole you just spotted in your microwave.

I bet that it is larger perforations on the gadget’s walls. The perforations are purposeful and are meant for good; to allow the bouncing of the waves in the cooking chamber. 

The hole you have spotted is unusual and large. So it is dangerous to have it in your microwave as it can cause several concerns;

  1. Mobile And Radio Networks Interruptions

A hole that is larger than 4 inches will cause microwave leakage. The waves cause mobile and radio network interruptions. The two wave frequencies clash, causing a loss in the network. Experts caution you not to put your phone in a microwave. A prolonged and intense leakage can make your phone burst in flames.

2. Wi-Fi Interference

Like the phone and radio network, microwaves interfere with wifi connectivity devices, more so wireless ones. These operate at a frequency close to that of microwave ovens (2.4 and 2.45 GHz). If your wifi router is within microwave proximity, the electromagnetic waves interfere with each other.

3. Interference With Remote Controlled Electronics

Leaking microwaves also affect electronic gadgets such as security alarms, TVs, and computers. It will also turn off Bluetooth lights. Beware of such leakages, switch off the microwave, report to the manufacturer, or buy a new oven.  

4. Health Hazard

There are hundreds of studies about microwave safety among users. Medical journals have published statistics on microwave injuries in the US. Indeed, numerous reports of people finding themselves in the ER due to such injuries. These include burns and eye problems. Intense microwave leakage can burn body tissues. So, stop using your microwave if it has a hole. Dispose of it and get a new device. 

You now know it is dangerous to use a microwave with a hole. Stop using the gadget and call the manufacturer. Explain the nature of the hole. Also, you can take a short video or picture to help the service guys to make swift decisions. If they spot a design flaw or damage, they can recall the device and access it if it is repairable.

Also, you need to establish why your oven has a hole so that you can be careful with your next microwave. That justifies our next subheading.

Why Your Microwave Has A Hole?

Learn here the causes of holes in microwaves;

Stubborn Stains

If food spatters in the cooking chamber, and you do not wipe it, it accumulates and becomes a stubborn stain. The dirt reacts with the paint and causes rusting. Failure to treat the rust can lead to a hole in the corners of your oven.

Such a microwave is unsafe for use in your home. Dispose of it and get a new gadget. Microwave hygiene is an essential maintenance procedure. Clean both the interior and exterior after use.


Spilled milk, water, soups, steam, and grease leave the surface moist. Like stubborn stains, moisture causes rust. Eventually, your oven develops holes. Ensure that you follow the right microwave hygiene practices. After cleaning, wipe it with a dry cloth to absorb all the moisture.


Old age causes appliances to deteriorate. The paint begins to peel off, exposing the surface to corrosion. Later, rusty holes develop. These are dangerous as they cause the release of microwaves from the oven.


While researching the cause of holes in the microwave, I came across a user whose fork left a hole in their oven. The object left a hole in the oven’s surface. That’s way too careless and risky. First, a metallic object in the microwave will cause it to arc. Arcing can cause fire or severe damage to the device’s crucial functions, including the diode and the magnetron.

With a tiny hole on the surface, there may be no radiation. But soon, the gap will get rusty and expand. Do not leave sharp objects inside your cookware. Also, place your oven on a flat, stable surface to prevent falls.


The microwave design includes holes on the surface to allow the bouncing of waves. The holes are in a specific alignment and are not random. Such perforations are not a cause for worry. Alert your dealer/manufacturer if you spot an abnormal hole in your oven.

Why Are There Holes In The Microwave?

As I mentioned before, microwaves come with holes. The holes come as a design and are on both the internal and external surfaces. 

Internal holes in a microwave oven

The internal ones allow the jouncing of radiations inside the cooking chamber. There are no exit holes for the waves to the external surface. Usually, these holes are similar in shape and are tiny. So, if you notice a larger hole in the microwave, take caution and call the manufacturer. Such a hole could be an escape route for radiation.

External holes in a microwave oven

The exterior holes you see on your oven’s back, sides, or top are breathers. They allow air in and out of the microwave. The perforations cool your microwave to ensure that it doesn’t overheat. So, have nothing to do with letting radiations out of the cooking chamber unless the chamber has a hole.

My Microwave Has A Hole In It. Is That Dangerous?

First of all, you need to determine the hole in your microwave. Inspect if it is in the plastic interior. Also, check if the spot is in your oven’s metal shielding. 

A hole in the plastic interior is not a cause to worry. However, on the metal shielding, it is not safe at all. It might damage connecting devices within a certain radius.

Also, the size of the hole in your microwave matters, as a perforation above a 4-inch diameter is dangerous. The waves will easily escape through the hole. Stray microwaves can burn your tissue and eyes.

Besides your safety, they will interfere with your radio and wifi networks. At extremes, it might damage your devices. The good news is microwave ovens do not emit nuclear radiation. So, even if they stray in your modern kitchen, the energy is not enough to cause cancer or other major biological alterations. At least, not like x-rays.

But you want to avoid cooking with a damaged oven. The best way to deal with a hole in your beloved microwave is to buy a new one. It doesn’t matter if it is on the door, roof, or your oven’s surface. You cannot risk fixing the hole, so take caution!

Related articles