Why should glass cookware with a hairline crack be avoided in high-heat ovens?

• A. It can fracture under extreme heat
• B. It cooks faster
• C. It becomes nonstick
• D. It cleans itself

Answer: (A)

Glass cookware is brittle and can fail under high heat because of thermal stress. A hairline crack creates a weak point where heat energy concentrates, and as the pan warms, that crack can propagate, leading to sudden fracture or shattering. This poses a serious burn hazard from hot glass and food being ejected. The safety concern isn’t about cooking speed, nonstick properties, or self-cleaning ability—it's about the cookware's compromised integrity in extreme heat. So, any cracked glass pan should be avoided in high-heat ovens.