Regular glass, also called annealed glass, is basic float glass that is cooled slowly after production without any strengthening treatment. It is widely used due to its low cost and clear finish, but it has a major safety limitation. When it breaks, it shatters into large, sharp, jagged shards that can cause serious injuries. In bathroom areas with wet and slippery floors, this type of breakage poses a higher risk of cuts and accidents. Because of this, regular glass is generally not recommended for shower screens or wet bathroom environments where safety is a priority. It may still be used in low-risk applications such as picture frames or decorative panels where impact risk is minimal. Always consider safety film. It is not ideal for shower use.

Tempered glass begins as regular annealed glass but undergoes a thermal strengthening process: heated to approximately 620°C and then rapidly cooled. This creates compressive stress on the surfaces and tension in the core, making the glass about 4 to 5 times stronger than annealed glass of the same thickness. When it breaks, tempered glass dices into small, pebble-like fragments with blunted edges instead of dangerous shards. This is why it is the standard (and often code-required) material for shower screens, glass doors, and frameless enclosures in Singapore It is widely used in modern bathroom design across residential and commercial buildings due to its safety performance and durability for shower use only.

Regular glass:
• Lower impact resistance
• Breaks into large, sharp shards
• Higher risk of deep lacerations
• Generally not permitted for shower screens under modern safety standards

For this reason, regular annealed glass is rarely used in new shower screen installations in Singapore.

Tempered glass:
• Significantly stronger than regular glass
•  Breaks into small, rounded fragments
•  Required by safety standards for high-impact areas like bathrooms
•  Safer overall, but not immune to sudden failure

Tempered glass greatly reduces the severity of breakage but does not eliminate all risks.

Yes, and this surprises many homeowners.

Tempered glass can fail due to edge damage, impact, installation stress, frame pressure, or long-term wear. One of the least-understood causes is nickel sulphide inclusion (NiS).

During manufacturing, microscopic nickel sulphide particles can become trapped in the glass. These particles can slowly expand at room temperature over months or years due to a phase change. In the highly stressed tempered glass, this tiny expansion can trigger a sudden, spontaneous fracture with no external impact.

This is an inherent characteristic of the tempering process and can occur even in high-quality glass from reputable manufacturers. Spontaneous breakage due to NiS is relatively rare (industry estimates often place the risk in the range of 1 in several hundred to several thousand panels, depending on conditions and whether heat-soak testing was performed), but when it happens, the entire panel can shatter almost instantly.

• Edge chips or damage during installation/renovation
• Stress from misaligned frames or fittings
• Impacts from hard objects (showerheads, taps, etc.)
• Thermal stress from extreme water temperatures
• Long-term fatigue in daily-use enclosures

In a small Singapore bathroom, a sudden full-panel collapse can still pose risks of cuts, shock, or slips — even with the safer fragment pattern.

Shower screens face unique conditions: daily heavy use by children and elderly family members, constant moisture, slippery floors, and very close proximity to users.
Tempered glass improves the type of fragments produced, but it does not prevent the pieces from scattering across the bathroom floor.
This is where protective window film (also called anti-shatter or safety film) fills the gap.

• Tempered glass cannot shatter on its own: It can — due to nickel sulphide inclusion or other stresses.
• Small pieces mean it is completely safe: The fragments are less likely to cause deep cuts, but a sudden collapse can still create hazards on a wet floor.
• Protective film is only for exterior windows: High-quality safety film like LLumar works effectively on interior glass, including shower screens.
• Tempered glass is enough by itself: It addresses fracture pattern; film adds crucial containment.
• Only cheap glass fails: NiS-related issues can affect glass from any manufacturer — it is a known characteristic of tempering, not always a quality defect.

Combining both is the most reassuring approach:

1). Tempered glass provides superior strength and safer breakage characteristics.

2). Protective safety film manages the fragments after breakage.

This combination is particularly valuable in Singapore homes, where bathrooms in HDB flats, condominiums, and landed properties are often compact and shared across generations. Older installations (5–10+ years) may also benefit from assessment, as they have had more time for potential stress factors to develop.

At Window-Cool, we specialise in LLumar anti-shatter protective film for shower screens and bathroom glass across Singapore. Our team can assess your existing setup and recommend the best solution for your family’s needs.