The law came about when they started using a lot of synthetics in children's wear and believe me those went up in seconds when held near a flame. Always the best to use is 100 percent cotton. So if you haven't checked it beware of polar fleece boy does it melt and flame fast. Every where you look they use it in baby and children's blankets and clothing. I no longer use it for grand kids things when I saw what happened to hubby's shirt at work. He leaned against his hot roller and was on fire! fortunately he was not hurt just singed but that would have been a different matter for a child.