What Happens If You Run a Non-Dishwasher Safe Item Through a Cleaning Cycle?

What Happens If You Run a Non-Dishwasher Safe Item Through a Cleaning Cycle?

Dishwashers are wonderful appliances. Along with saving you from the task of washing your dishes by hand, these machines are designed to give your dirty plates and utensils a deep and thorough clean—without using as much water as you would in the sink. "A normal dishwasher cycle uses less than three-and-a-half gallons of water, the same as hand-washing dishes for just over two minutes," explains Cynthia Fanning, the Vice President of Product Management, Dishwashers for GE Appliances. "By trusting your dishwasher to do the cleanup, you can help conserve hundreds of gallons of water a year."

Unfortunately, not all dishes were created equal. While some are composed of dishwasher-safe materials, like ceramic and stainless steel, others become damaged when exposed to heat and water pressure. "Both dishwashers and dishes have evolved a lot over the years," Fanning says. "There are more items that are dishwasher-safe than there used to be." Curious about what could go wrong when you run non-dishwasher safe items through the dishwasher? From fine china to wooden spoons and more, here's what happens to those off-limits pieces when they're exposed to a washing cycle.

Related: How to Clean Your Dishwasher

boy loading dishwasher with father
boy loading dishwasher with father

Getty / martin-dm

Fine China

Despite advancements in dishwasher-safe materials, Fanning says that one type of product that should never go into a dishwasher is fine china. "Detergent chemistry can cause the paint on the dinnerware to chip or wear off," she explains. "Additionally, the sizes of fine china tend to be different from standard plates, which can create extra movement and rattling that can cause damage."


While many plastic items, including BPA-free and polypropylene ones, are safe to use in the dishwasher, others can quickly warp or melt when exposed to hot water and the heat from the drying cycle. For this reason, you should only put plastic wares, such as food containers, that are marked dishwasher-safe in your dishwasher and always on the top rack—which is further from the heating elements located in the bottom of most models.


No matter how dirty your beloved wooden spoons or cutting board may be, don't put them in this appliance. Hot water can cause wood to warp, splinter, crack, and lose its finish—and even a small crack or splinter in a wooden utensil, bowl, or board can trap disease-causing germs and bacteria that you don't want anywhere near your food. Stick to hand-washing your wood or wooden-handled items to ensure they're safe to use for longer.

Non-Enameled Cast Iron

As a rule of thumb, pots, pans, and skillets composed of non-enameled cast iron are best kept out of the dishwasher. Not only can the detergents and water pressure cause your cast iron items to rust, your machine can also strip away the valuable seasoning oils that have accumulated on your cookware over time. Unless your cast ironware is enameled, it should be cleaned with water and a damp cloth only—no soap.

Fragile Glassware

As risky as it may seem, a lot of us still try to wash fragile glassware in the dishwasher. Even when placed on the top rack, delicate glasses can chip, crack, and split. Even worse, fragile glasswares, such as long-stemmed wine glasses, can get knocked loose during the wash cycle; they can hit against each other and shatter, leaving you with a dangerous mess to clean up.