I agree with LadyElisabeth for the very same reasons. Synthetic fabrics MELT onto the skin. I've known people that were wearing synthetic clothing during fires and suffered terrible burns as a result. It's not something that we ever want to think about but it does happen. DH is a firefighter and we are both hot air balloon pilots. We only ever wear cotton clothing while ballooning and it is what we recommend to all of our passengers. We've never had an issue, thank God, but there's always a first time. It's all I ever wear responding to fire calls even just as an auxiliary member.