The South African National Standards clearly state that frameless glass balustrade systems must be designed and tested in consultation with a professional structural engineer according to the SANS deemed to satisfy rules.
After engineers calculations have been done, one of the many physical tests that are performed on a frameless glass balustrade design is a 400 Joule Soft Body Impact Test. This test will be set up according to the testing specifications indicated by SANS and ultimately, this physical test will confirm whether a frameless glass balustrade system is safe for its intended use or not. It must be noted that the balustrade will be struck at its weakest point during the impact test, which normally would be where the stainless steel fitting fits through the glass in order to fix the glass to the system.
The below image shows how the fixing point is the weakest point of the system:
Here is an example of a 400 Joule Soft Body Impact Test as per SANS testing requirements. In this test the frameless glass balustrade has failed the impact test due to the exclusion of a handrail that is supposed to stabilize the system and spread the load upon impact.
Three reasons why a frameless glass balustrade will fail an impact test:
1. When the balustrade system is not designed and tested in consultation with a professional structural engineer, there could be questionable differences in material thicknesses, fixing components and material quality which could result in a balustrade system that is not safe for its intended use and will not protect those utilising the home, should any accidents occur.
2. When the balustrade system has not been fixed to the surface as per SANS deemed to satisfy rules, there is no guarantee that the balustrade system will remain intact in the fixing surface for the remainder of its life cycle. This is also true for any noticeable unstable or deteriorated surface that has not been taken into account when a balustrade is being fixed to it.
3. When designing and testing a frameless glass balustrade in consultation with a professional structural engineer, it will be evident that a frameless glass panel that is not fixed into a permanent steel or concrete channel to the specified depths, will require a handrail in order to withstand the load that is being impacted upon the system. Unfortunately, unscrupulous balustrade contractors will deliberately leave out the handrail in order to save on costs and win the job. This conduct is negligent and could impact on the safety of those utilising the building as seen in the impact test video above.