|A customer recently brought his microwave into our shop reporting that it was leaking microwaves. I had asked him on the phone how he knew this and he said the leakage meter that he had bought online was reporting leakage. He brought that tester with him and sure enough, in our workshop the meter reported leakage. However, we then immediately tested for leakage with our professional test meter and found no leakage at all. Upon close inspection we found that at very best the cheap meter just monitored the prescence of electrical noise, the result of any electrical motor operating will generate. It had nothing to do with measuring the prescence of microwaves.
We looked on ebay and found his meter and another both available for less than £10. Bought them both and of course in the workshop report leakage. In fact we found anything that had a transformer would show as a reading.
In our opinion these testers are completely rubbish and certainly not to be used as microwave testers. Our advice would be that if you have any concerns about microwave leakage to contact us (or your local microwave engineer) and we can test your microwave for leakage using a professional, calibrated test meter.
Incidentally, we always test a microwave for leakage after any repair as part of our workshop procedure and only very rarely find any leakage so it isnt something that should concern domestic customers. Commercial customers will have microwaves tested regularly anyway as part of their employees Heath and Safety commitment.