So I have one of those Bluetooth thermometers for meat and other foods. I heard it wasn’t supposed to work in my oven, because it’s a combination of a regular oven in the microwave. Since microwaves are supposed to be a faraday cage, it was my understanding that no radiation should be able to get out.

On the other hand, Bluetooth sensors are so incredibly sensitive, that my microwave might still be well within safe margins in terms of escaping microwaves.

It’s worth pointing out that the reception on my Bluetooth thermometer doesn’t work very well, but if I hold my mobile phone in certain places near the oven and will shortly catch a signal.

Should I be worried and buy a new oven?

  • zkikiz@lemmy.ml
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    1 year ago

    If you can’t feel your hand heating up if you hold it near the oven and sensors or thermometer strips don’t register any temperature increase outside the oven when it’s on then nothing substantial is escaping. The amount of 2.4ghz energy required for indoor communication is on the order of tenths or hundredths of a watt, whereas the amount of energy required to cook food is on the order of 1000 watts. So you’re talking about a 10,000-100,000-fold difference in magnitude.

    For non-ionizing EM radiation like radio waves and normal light (as opposed to ionizing radiation that can cause cancer by knocking bits off your DNA like UV rays and X rays) the danger is in, essentially, cooking your flesh. For radio professionals determining if a microwave antenna or cell phone is safe for your body, we calculate watts per square centimeter, in other words how much electrical energy is delivered to your skin’s surface. When a radio professional messes up and gets exposed to dangerous levels of energy, they experience it as feeling very warm or burning, and may suffer symptoms similar to a sunburn or, worst case, like putting a body part in a microwave oven.

    Also because of how rays of energy work mathematically against surfaces, every foot you stand away will exponentially decrease the amount of energy you’d possibly receive: standing 6 feet away will give you 2.8% the dose versus standing 1 foot away. So even if you have a dangerously defective oven, just don’t hang out with your face pressed to the glass and you’ll have much bigger things to worry about in life.

    TLDR: there’s no voodoo scariness behind microwaves, just try to make sure they’re not warming you up and cooking you, especially for extended periods of time. You’d probably notice if they were.

    The main hazard of putting an electronic device in a microwave is that it heats up and catches fire or ruins your food.

    • NotSpez@lemm.eeOP
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      1 year ago

      Thanks for the great and detailed answer. Another great day to be on Lemmy!

    • Neato@kbin.social
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      1 year ago

      Unfortunately by the time it’s heating up your hand, it may have already done permanent damage to more sensitive body parts. Your eyes are particularly sensitive to microwaves as they don’t have the blood flow to carry away heat. Causing cataracts. When I worked with RF it was one of the things they warned me of.

      • zkikiz@lemmy.ml
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        1 year ago

        Yes this is a good point, you don’t want i.e. tiny capillaries in areas with low circulation to be heating up before you notice other places.

  • Screak42@infosec.pub
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    1 year ago

    I’d be more worried to put something with a battery in an environment of like 200 degrees Celsius. I hope I’m just wrong … but to me that sounds like fire

    • Catsrules@lemmy.ml
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      1 year ago

      My bluetooth headphone cut out when my microwave is on. I know my WiFi also has issues streaming video when the microwave is on as well. When I was little I had a remote control car that if you turn it on and then turn on the micrwave the car would randomly start and stop driving by itself. Crazy stuff with microwaves.

  • blackbrook@mander.xyz
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    1 year ago

    Microwave ovens are enclosed in a cage designed to stop the particular wavelength of radiation they emit. I suspect this has been confused with a Faraday cage.

    • jmcs@discuss.tchncs.de
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      1 year ago

      You mean they are supposed to block exactly the same 2.4Ghz to 2.5Ghz range that both regular consumer microwave ovens and Bluetooth use?

  • Norah - She/They@lemmy.blahaj.zone
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    1 year ago

    Modern microwaves use 2.4Ghz frequency waves to cook food, as it means they can “leak” up to what say, a wifi router, is allowed to broadcast. This is also considered a safe amount to be around. The amount that’s actually produced is also much higher than what escapes. Still, a bargain model is more likely to emit a “louder and dirtier” signal.

    It sounds like your microwave is managing to target a narrow enough frequency band that it’s not interfering with the BT signal on a different part of the spectrum. Maybe the shielding is similarly finely tuned?

    • FrickAndMortar@lemmy.ml
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      1 year ago

      I learned about this when we got a new microwave and every time we used it, it would kill the wireless connection to my laptop!

  • bstix@feddit.dk
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    1 year ago

    Well, you should definitely not microwave any kind of electronics, but it should be safe to use the convection oven though reception would be bad.

    Personally I prefer the simple non-digital roasting thermometers. That’s a cheaper option than getting a new oven.

    • NotSpez@lemm.eeOP
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      1 year ago

      Thanks! To be clear, I would never use the thermometer while microwaving food. Only when using the oven function. My concern was whether or not I had stumbled upon a safety issue lf the microwave function of the oven.

      Also, I can definitely recommend a precise and predictive thermometer. They’re awesome gadgets if you’re into that kind of stuff.