Heat Soaked Testing Glass EN 14179-1
REASONS FOR HEAT SOAK TESTING
By the nature of the product toughened glass can spontaneously break sometimes months or even years after installation. When it happens it can sometimes be upsetting for people if in close proximity and causes disruption in the location not at least the cost of replacement.
Although other reasons exist for breakage mainly vandalism or edge damage, a Nickel sulphide inclusion (Nis) in the glass is initially implicated. Considering there is no full proof method to detect Nis in the glass manufacture processing it is passed on to the processors. Nis is only consider to be a problem when the glass is toughened or heat strengthened. The only detection is displayed at the point of breakage when it occurs.
Nis is considered to be very rare one in every 400 tons however Toughglaze recommend for every glass to be heat soak tested which reduces the chances of this happening.