Why microwave oven safety matters Four tips for using your microwave safely

Do you use microwaves at your offices or in your business premises? It’s very likely you do because they’re such a convenient facility to have in small kitchen spaces (and it means you can eat something other than sandwiches sometimes!). But because of the way they heat up food, sometimes it’s easy to forget they’re ovens. And because we use them for speed and convenience it’s also easy to let the fact that there are certain rules about using them slip our minds. Microwave ovens create heat by producing waves of electromagnetic radiation. That causes the water molecules in the food to vibrate and it’s that vibration that produces the heat. But even though they don’t ‘heat up’ in the more obvious way a conventional oven does, they can still pose a safety risk and that includes being a potential fire hazard. Why?Well, one significant reason is because if there’s no moisture available when the microwave’s heating something up, other less volatile molecules absorb the radiation and start to heat. Any material which has dried out can overheat and that can lead to a fire starting in the microwave. (That’s why wheatbags are notorious – if you’re a user, put a cup of water in the microwave while you’re heating it). So it’s worth reminding yourself of some of the most important rules for using microwaves safely.


It’s likely you already know in most instances you mustn’t put anything metal in a microwave. If you do, it results in a process called arcing and that’s when sparks fly and the fire risk increases. But metals can get in there unnoticed - for example, on metal-edged bowls or twist ties. And did you know you shouldn’t use recycled paper products in microwaves unless they’re specifically approved for microwave use? That’s because products like recycled paper towels and kitchen rolls can have tiny metal flecks in them which have the potential to ignite.


Because most people know they shouldn’t use metal in microwaves there can be a tendency to assume plastic is safe. But not all plastic containers are suitable. Check before you use them as certain containers, foam trays and plastic wraps aren’t heat stable at high temperatures. If they melt or warp, harmful chemicals could be released into the food.


Be extremely careful when you’re taking the heated food or liquid out of the microwave. Even if the container only feels warm, the contents could be very hot and give you a painful burn. Ideally, let the food or liquid sit for a minute before you get it out and use oven gloves if possible. But even then take your time if you’re lifting off a cover or wrapping because there may still be very hot steam inside which could escape suddenly.


Odds are a microwave in a workplace is less likely to get a good clean than one in your home (who really wants to scrape off someone else’s dried-on tomato soup splashes?). But a build-up of food inside the microwave isn’t just unhygienic. It increases the risk of fire so it’s important that it’s cleaned off regularly. Always unplug the microwave first and clean the inside of the door as well as the oven cavity.

What should you do if a fire starts?

Follow our tips and hopefully you’ll never have to deal with a microwave fire. But it’s worth knowing what to do just in case. Turn off the microwave straight away; you need to stop the fan so it’s not drawing in oxygen. If it’s safe to do so, unplug the power cord.  Keep the microwave door shut as this should lead to the fire suffocating - never open the door until you are certain the fire is out. But always remember if you’re unsure about what to do or the fire isn’t dying down despite your actions the usual rules apply. In other words get out quickly, raise the alarm and call the fire service immediately.

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