Sodium hydroxide 100% Physical / chemical hazards: Non-combustible. Contact with moisture or water can generate enough heat to ignite flammable substances. Reacts with certain metals (eg aluminum) to produce flammable hydrogen gas.
Storage: Moisture absorbing. Store in a cool, dry place. Protect packaging from physical breakage. Follow all warnings and precautions for this substance. Store in an acid-proof concrete floor area. Incompatible materials: strong acids, especially nitric, hydrochloric, sulfuric, etc. acids, strong oxidants, strong reducing agents, some metals (zinc, aluminum, tin, lead), flammable liquids. Packaging requirements: tightly closed plastic bags made of polyethylene-treated paper with inner bags made of polyethylene or polypropylene. Do not use metal containers.