Any fruit or vegetable that occurs, grows naturally, and is sold in a specific region or locality.
Natural barrier
Any area where lack of flammable material obstructs the spread of wildfires.
Natural clay tile
A ceramic mosaic tile or a paver tile made by either the dust-pressed or the plastic method from clays which produce a dense body and a distinctive slightly textured appearance.
Natural cooling
Space cooling achieved by shading, natural (unassisted, as opposed to forced) ventilation, conduction control, radiation, and evaporation; also called passive cooling.
Natural draft
Draft that is caused by temperature differences in the air.
Natural draft cooling tower
A cooling tower using natural air circulation to cool water or another liquid. Used in power plants and chemical refineries.
Natural finish
A finish applied to wood that provides protection without masking the natural grain and color.
Natural gas
A naturally occurring gas used as a fuel in furnaces and power plants. Natural gas is commonly found in oil-producing areas.
Natural gas steam reforming production
A two step process where in the first step natural gas is exposed to a high-temperature steam to produce hydrogen, carbon monoxide, and carbon dioxide. The second step is to convert the carbon monoxide with steam to produce additional hydrogen and carbon dioxide.
