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Microwave symbols: 5 things you should never put in the microwave

Read on to discover the microwave safe symbol and 5 things you should never put in a microwave.


Reading Time: 2 minutes

microwave in the kitchen

Key steps

  • Check for a symbol that looks like a mini microwave with wavy lines on the door to know that your container or cookware is microwave safe.

  • Never put metal, paper bags, Styrofoam or plastic containers without the microwave safe symbol into the microwave.

The best match for busy families, a microwave can save us some time when cooking; but do you know how to use one properly? What about the containers you can and can’t use when heating food? In this article, we’ll explain how to spot the microwave safe symbol and give a list of things you should never put in the microwave.

If you don’t see the microwave safe symbol on a plastic container, don’t use it. It could do more than just melt; it could release chemicals into your food too!

What is the microwave symbol to look out for?

If you’re wondering about the microwave safe symbol, all you need to look for is a small microwave shape with squiggly lines on the door. With some modern containers and plates, you may find advice on the base of the product such as ‘Suitable for microwaving’ or ‘Not suitable for use in the microwave’.

Is it microwave safe? 5 things you should never put in the microwave

Now you know how to spot the microwave safe plastic symbol on containers and other materials, here is our list of 5 things you should never put into the microwave.

  1. Paper bags: not only are these a potential fire hazard, but putting them in the microwave could also release dangerous toxins.

  2. Yoghurt, butter or spread containers: while washing out and reusing these for storage is eco-friendly, they are not designed to withstand high temperatures and could melt or release chemicals into your food.

  3. Styrofoam: don’t be tempted to microwave your midnight kebab shop takeaway in its Styrofoam container. This is one type of plastic that is not microwave safe.

  4. Anything metal: from cutlery and metal travel mugs to bowls or other cookware with a metal trim, never put metal in the microwave. The sparks caused could lead to an explosion.

  5. Any plastic without the microwave safe symbol: for the same reasons as the above containers (melting and chemicals in your food) only use plastic containers that you are 100% certain are microwave safe.

Now you know which microwave safe containers to use and which non-safe products avoid.

With this simple article, you now have everything you need to understand how to spot microwave safe plastics and other materials – and you can save time cooking!

Originally published