I tested one last week. A soup bowl of water in a 1000w microwave. The water, if it was soup, would be too hot to consume. I think the time was 2 min. 15 sec. I will now do several more timed test in an older microwave outside to see what it would take to light one off??? I used only 100% cotton, I repeat 100% cotton fabric, batting and thread in my projects. I also noted that these bowl liners are readily available for sale on the net. Not sure why some have ignited, but I hope to find out.
Soman2
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