Safety is the paramount concern for shower doors. You must prioritize Tempered Safety Glass that complies with international standards such as EN 12150-1 (EU) or ANSI Z97.1 (US). For standard residential use, a thickness of 6mm to 8mm is ideal, while high-end frameless designs often require 10mm glass for structural integrity. Additionally, look for glass with an Easy-Clean coating (Nano-coating), which reduces water spots and limescale buildup by up to 90%, significantly lowering maintenance costs for end-users.