IFC Chapter 27 regulates hazardous materials including flammable liquids, compressed gases, oxidizers, unstable (reactive) materials, and toxic substances. Maximum allowable quantities are specified for each hazard class. Flammable liquids in aggregate not exceeding 120 gallons can be stored in approved cabinets without additional protection. Compressed gases in cylinders must be secured and protected from physical damage. Outdoor storage of hazardous materials requires specific setbacks from buildings and property lines. Indoor storage requires fire-resistance-rated rooms with proper ventilation. Incompatible materials must be separated to prevent reactions if containers leak. Emergency response information must be provided through labels and safety data sheets.