Our guild enjoyed a wonderful presentation on flammability of various battings. Using a 10-second test, samples of various batting fibers were tested. 4X4" batts were placed on corelle-type saucers. Demonstration was performed by a long-arm quilter using a BIC pistol lighter, and she touched the flame to the batting as an assistant started the timer countdown.
Polyesters flame up quickly and melt potentially creating terrible burns. Cotton is a much slower burn. Many flame-retardant cotton bats lose that feature after repeated launderings. 80/20 Hobbs burned faster than 100% cotton. Wool put itself out. Some of the new flame retardant batting did well in the test.
The quickest burn was the bamboo. Flash fire is how I would describe it. The lapsed time was less than 3 seconds, as I recall. Even the polyesters took longer than that. I would caution anyone to avoid bamboo use in a child's quilt, or lap throws for the elderly.
After reading earlier responses about the manufacturing process, I can see why the bamboo burn test had that result.
I love the drape and feel of bamboo, but the test I witnessed was so shocking, I felt I needed to pass the information on. I will still occasionally bamboo, but likely use it in wall hangings and table toppers.
I love wool, and since I remove bed quilts from the bed entirely before getting under the covers, I don't experience sensitivity to wool than I might if I slept under it. It's very expensive, however, so I don't use it often, but I do prefer it.
The demo was eye-opening. The long-armer has refused to use poly in a baby quilt, and said she will not use bamboo either after seeing the results of her test. Before that, she had believed bamboo was like cotton. The audiences she'd shared this information with were all as surprised as she had been.