Tempered Glass

Process and glass types

• Glass is heated to approximately 650 °C then rapidly cooled, creating surface compression and internal tension.
• Plate, sheet and float glass may be used, including clear, super-clear, tinted and suitable patterned glass.
• Satin, sandblasted, ceramic-coated, reflective, Low-E, self-cleaning and hydrophobic products require coating compatibility checks before tempering.
• Mirror and color-coated products must be tempered before their final coating is applied.

Advantages

• 4–5× mechanical strength and heat resistance vs. annealed glass
• Fractures into small honeycomb granules without sharp edges — safety glass per EN 12150
• Withstands heat up to 290 °C and sudden temperature changes up to 150 °C
• Used for spotlight fittings, fireguards, gas stove bases and hot-pot stands

Application

• High-impact or wind-exposed areas — squash courts, sports field barriers, ice hockey and skating rinks
• Mandatory safety glazing next to fittings: doors, low windows, balustrades
• Shower doors, staircase enclosures, glass fences and general decoration

Limitations and inspection

• Tempering can introduce controlled roller wave or bow.
• Nickel-sulfide inclusions can cause spontaneous breakage at roughly 8 panes per 1,000; a butterfly fracture may indicate NiS.
• Tempering can be verified by destructive testing, laser equipment or polarizing film.
• Minimum production size is 180 × 180 mm or a diagonal over 250 mm; site dimensions and installation clearances must be confirmed before production.

Caution in use

• Tempered glass is not fire-resistant — unsuitable as a fire barrier or an oven peephole above 290 °C
• Cannot be cut, drilled or edge-worked after tempering; all holes and edging must be specified before processing
• Avoid edge pressure, levering and direct contact with hard materials during installation.
• Do not use a single tempered pane for roofs, high-rise façades, floors or stairs; use an appropriately designed laminated construction

Specifications