I grew up around kerosene heaters used as both the heat source at the flea market inside my father's store and inside our home. So when my husband asked if we should get a kerosene heater the nostalgia was exciting.
We bought a brand new heater with the thought that is should run cleaner than a used one.
We only had it lit for a couple of hours when I realized my eyes were burning, lungs were tight and I felt dizzy with brain fog.
My husband had a thought, was the wick fiberglass? He looked it up and sure enough the top part of the wick where the flame burns was indeed fiberglass. We turned the heater off.
With some research my husband found an all cotton wick and ordered one. When it arrived in the mail he removed the fiberglass wick and installed the all cotton wick. This time I had no negative reaction when the heater was lit. When I was a kid the wicks were all made from cotton. Apparently now it's common for kerosene wicks to contain fiberglass at the top where the flame burns and be made of cotton at the bottom to soak up the kerosene.