Graham - I had never thought about this issue (since the early days of microwave ovens…late 70’s)…but I put the question to Grok AI. If you are reading 146 mW/m3, I would get rid of that unit and buy a new one. Use the google search to find forum threads from folks who have bought new microwaves to get ideas for brands and models that fit, and installation tips.
Here is Grok’s answer to “Do modern microwave ovens leak harmful amounts of RF waves?”
Modern microwave ovens are designed with safety in mind and are subject to strict regulations to minimize radiofrequency (RF) leakage. When functioning properly and used according to manufacturer instructions, they do not leak harmful levels of RF waves.
Here’s a breakdown of the key points:
Microwave ovens operate by emitting non-ionizing RF radiation at a frequency of about 2.45 GHz to heat food. This type of radiation doesn’t have enough energy to break chemical bonds or cause DNA damage, unlike ionizing radiation (e.g., X-rays or gamma rays). The primary concern with leakage would be potential thermal effects—essentially, heating of body tissue—if exposure were significant.
In the U.S., the FDA sets a safety standard that microwave ovens must not leak more than 5 milliwatts per square centimeter (mW/cm²) at 5 cm from the oven surface over the product’s lifetime. Most modern microwaves leak far less than this—typically under 1 mW/cm²—due to improved shielding, interlock systems (which shut off the microwave when the door is opened), and robust design. Studies and tests, including those by consumer safety organizations, consistently show that leakage from well-maintained microwaves is negligible and well below levels that could cause harm.
That said, damage or wear—like a cracked door, broken seal, or faulty latch—could increase leakage. Even then, the risk remains low because RF energy drops off rapidly with distance (following the inverse square law). Standing a foot or two away, as most people do, reduces exposure to virtually nothing. For context, international guidelines (e.g., ICNIRP) suggest safe exposure limits for the general public at 10 W/m² (1 mW/cm²) for prolonged periods, and microwave leakage is a tiny fraction of that.
There’s no credible evidence linking typical microwave oven use to health issues from RF leakage. Concerns sometimes arise from confusion with older models (pre-1970s), which had less stringent standards, or from misinformation online. If you’re worried, you can buy an inexpensive RF leakage detector to check your oven, but for a modern, undamaged unit, you’re almost certainly fine.
So, no, modern microwave ovens don’t leak harmful RF waves under normal conditions. Just don’t press your face against a cracked door while it’s running—common sense applies.
