Garages, cleaning plants and all other places where volatile wastes are produced need a garage basin unit to avoid the possibility of an explosion in the sewage system. Volatile liquids are lighter than water and they rise to the surface thus allowing evaporation to occur. The fumes are vented into the air, leaving the waste matter safe to pass into the sewer system. Each of the three basins has a gas-tight cover, 2 inch vent, and can be fitted with 4 inch or 6 inch standard hubs. Available in standard diameters: 18 inch, 24 inch, 30 inch, 36 inch, 42 inch, 48 inch, 60 inch, and 72 inch, depth is as specified