How should buyers choose between 304 and 316L stainless steel plate for corrosive environments?

How should buyers choose between 304 and 316L stainless steel plate for corrosive environments?
The choice hinges on exposure. 304, with roughly 18% chromium and 8% nickel, resists atmospheric and fresh-water corrosion and suits kitchen equipment, indoor enclosures and general machinery. 316L adds molybdenum and a low-carbon design, sharply improving resistance to seawater, acids, alkalis and chemical media, making it the default for marine hardware, chemical piping and medical devices, at a higher cost. For 1-30mm plate, processing matters as much as grade: high-power laser cutting with nitrogen assist preserves corrosion resistance and holds tolerances near plus or minus 0.08mm, avoiding secondary pickling.