The Break Ability of Tempered Glasses

 Tempered glass is one of the preferred materials in buildings. It is used as a structural element in curtain walls, but we also find it in other more frequent places such as canopies at bus stops, shower enclosure glass in the bathroom as well as at doorways. In this article, we look at the strengths and fragility of tempered glasses.

The strengths

The tempered safety glass used in the shower enclosures is manufactured by heating the normal glass above 650º, then cooling it with cold air. This makes it five times more resistant to breakage than normal glass.

The tempered glass receives thermal treatment in its manufacture that gives it special mechanical properties such as high resistance to impact or resistance of a strong thermal gradient, among others.

But the characteristic that really distinguishes it and makes it preferable to other types of glass is that it is a safety glass. In case of breakage, the resulting fragments are small and their edges do not have sharp edges. It complies with the UNE-EN 12150 standard. It cannot cause serious injuries to people, in contrast to the slabs that form on other types of glass.

The drawback

Tempered glass presents a potentially serious problem – its spontaneous breakage. Due to the machinery itself, the fuels and the finishers used in its manufacture, a chemical compound, nickel sulfide (NiS) inclusions may appear in the glass.

Initially, these inclusions are in alpha phase; but during the cooling of the glass, they undergo a phase change that entails an increase in volume (of 2.8%, approximately), sufficient to produce the breakage of the glass in case the inclusion is in the area of ​​a tensile strain of the glass.

The problem is that this phase change occurs without prior notice and does not occur immediately during cooling, but may take between 5 and up to 10 years to occur, with the glass already in service. This phenomenon, studied since 1961 by Ballantyne, is still a problem today.

When does the tempered safety glass of the shower break?

In this part, we tell you what happens if the tempered safety glass of the shower screens breaks. To avoid breakage, you should always rest the doors very carefully on cardboard or blanket. Once the screen is installed, glass breakage is almost impossible. The tempered glass can not be cut or pierced, as it would produce its breakage.

The spontaneous breakage of tempered glass happens rarely and is due to the fact that the glass contains small particles of nickel sulfide that, over time, an increase in volume by 2 or 4%. This can cause stresses that lead to spontaneous breakage.

In the event that the glass is broken, it fragments into thousands of small pieces, but they are not dangerous. The chances of causing sharp or deep wounds are minimal. It is important that you know what glass protectors are. The screens of tempered glasses are difficult to break, except that it is hit on the edges. 99.99% of the breakage of tempered glass in the screens occurs at the time of installation. The cause of breakage during installation is usually because the glass door is hit against the ceramic floor or shower tray.

In the case where you have a shattered shower door and you need a replacement made, do call in trusted hands. Glass and Door MD runs a 24-hour service. Contact them and they will help you with a swift window or shower door glass replacement.