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Safety Glass Glass can be dangerous if it breaks. It can make sharp pieces. For doors and some windows, engineers use safety glass. There are two main types. One type is tempered glass. When it breaks, it breaks into many small, dull pieces, like a car window. It does not make sharp pieces. The other type is laminated glass. It has a plastic layer inside. If it breaks, the glass sticks to the plastic. It does not fall apart. CONVERSATION 3: A Broken Window A site manager is talking to a wor