An internal floating roof tank suffers less evaporation loss and emissions than a comparable external floating roof tank. Emission and losses from roof seals are effected
by wind speed. Since the wind speed above the seals in an internal floating roof is almost zero, the emission of air pollutants is minimized.
Either a conventional steel roof or a dome roof will have the same effect on emissions. However, the geodesic dome has an advantage that is not available with a conventional
roof. Large steel roofs, on internal floating roof applications, must be supported by columns. These support columns must penetrate the roof.
At each penetration there are some emissions. Because the geodesic dome roof is a clear-span structure, or a structure that is supported entirely at the perimeter, there
is no internal roof penetration. See Figures