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It started like any ordinary evening.
Dinner was over, the kitchen was a mess, and I began loading the dishwasher without giving it much thought. Plates, bowls, cups, glasses—it all went in as usual. I added the detergent, closed the door, pressed the start button, and walked away.
About an hour later, I heard a loud bang.
At first, I thought something had fallen off a shelf upstairs. Then came another sharp cracking sound.
When I rushed into the kitchen, I couldn’t believe what I was seeing.
The dishwasher door had burst open, and tiny pieces of shattered glass were scattered across the floor, inside the machine, and even several feet away on the kitchen cabinets. It looked as though someone had dumped an entire box of broken glass into the room.
Thankfully, my children were in the living room and nowhere near the kitchen.
After making sure everyone was safe, I unplugged the dishwasher and carefully cleaned up the dangerous mess. I couldn’t understand what had happened. The appliance had always worked perfectly.
The next morning, I called a local appliance repair technician.
When he arrived, he inspected the dishwasher carefully before asking a surprisingly simple question.
“What kind of dishes did you wash?”
I showed him what was left of the broken items, expecting him to point to a mechanical problem.
Instead, he shook his head.
“Your dishwasher didn’t fail,” he explained. “One of the items inside wasn’t designed for dishwasher temperatures. When it shattered, the pressure and spinning spray arms spread the glass everywhere.”
That conversation completely changed the way I use my dishwasher.
The technician explained that while dishwashers are incredibly convenient, they’re not safe for every kitchen item. High temperatures, powerful water pressure, and strong detergents can permanently damage certain materials—or even create dangerous situations like the one I experienced.
The first thing he mentioned was ordinary glassware.
Many inexpensive drinking glasses are not made from tempered or dishwasher-safe glass. Tiny scratches weaken the glass over time, and repeated heating and cooling eventually causes it to shatter without warning.
Crystal was next on his list.
Beautiful crystal glasses may sparkle on a dining table, but dishwasher heat can leave them cloudy, chipped, or cracked. Hand washing is almost always the safest choice.
Then he pointed to my favorite chef’s knife.
Dishwashers are terrible for quality knives. The hot water dulls the blade, detergents can corrode the metal, and the knife may also damage the dishwasher racks or become dangerous while unloading.
Wooden utensils were another surprise.
Wood absorbs water. After repeated dishwasher cycles, wooden spoons, cutting boards, and rolling pins often crack, warp, or split apart. The finish wears away, leaving them rough and more difficult to clean properly.
Cast iron cookware should never enter the dishwasher either.
The detergent strips away the protective seasoning that makes cast iron naturally non-stick. After one cycle, rust can begin forming surprisingly quickly.
Copper cookware also suffers.
Dishwasher detergent reacts with copper, causing discoloration and dullness that is difficult to restore.
Non-stick pans deserve extra care as well.