Mezzanine Understructure: Extruded aluminum C-Channels or I-Beams. Tubular Aluminum Columns.

Mezzanine Stairs, Gates, and Handrail: Common Stairs: OSHA and BOCA. Common Handrail: Horizontal 2 and 3 Rail.  Common Gates: Lift Out, Swing, and Sliding Gates.  For more info see Mezzanine Stairs, Mezzanine Gates, Mezzanine Guardrail.

Decking Options: Common varieties are: Aluminum Plank Grating, Fiberglass Bar Grating.  For more info see Mezzanine Decking.

Finishes: Anodized Aluminum.  For more info see Mezzanine Finishes.

Benefits: Aluminum, like fiberglass, is impervious to rust.  Aluminum mezzanine systems can be safely immersed in water without worry.  Aluminum is also very light so many smaller mobile work platforms are made from aluminum.

Drawbacks: Aluminum is not nearly as strong as steel so it is generally not used to support heavy loads.  The column spans are decreased to around 10' max.  Oh yeah, one more thing, Aluminum is about 3-5 times more expensive than steel!