AS/NZS 2208, EN 12150, and ASTM C1048 are three widely used standards for tempered glass in Australia/New Zealand, Europe, and the United States, respectively. While all three standards cover similar requirements and testing methods, there are some differences in their specifications for flatness requirements in tempered glass.
In general, all three standards specify that tempered glass must meet certain dimensional tolerances for thickness, length, width, and flatness. They also specify that the position of any holes or cutouts in the glass must meet certain tolerances to ensure that they do not weaken the structural integrity of the glass.
However, there are some differences between AS/NZS 2208, EN 12150, and ASTM C1048 when it comes to the flatness requirements of tempered glass: