Serta® takes bedroom fire safety very seriously. None of us wants to consider a home fire, but they do happen. Just as you have taken precautions with installing fire alarms, fire extinguishers and other home safety products, you now have the choice to buy a Serta® mattress with an advanced open-flame resistance system. FireBlocker® is a blend of fibers that slows the spread of an open-flame into a flame into a mattress.