Protein foams contain natural proteins as the foaming agents. Unlike synthetic foams, protein foams are bio-degradable. They flow and spread slower, but provide a foam blanket that is more heat-resistant and more durable. Protein foams include regular protein foam (P), fluoroprotein foam (FP), film-forming fluoroprotein (FFFP), alcohol-resistant fluoroprotein foam (AR-FP), and alcohol-resistant film-forming fluoroprotein (AR-FFFP). Protein Foam from non-animal sources is preferred because of the possible threats of biological contaminants like prions