Bird protection glass: Contrasts in the visible and UV spectrum
Glas Marte has developed bird protection glass that combines bird collision prevention, transparency and design freedom. The partially applied GM LIGHT CHROME® coating creates distinct contrasts both in the visible spectrum and in the ultraviolet (UV) spectrum, which is invisible to humans. The UV reflectance is 34.87% on coated areas, compared with 4.69% on uncoated areas. The values in the visible spectrum are also comparable to those of bird protection glass products that have achieved positive test results.
The technology has already been used with positive practical experience in numerous demanding projects, including the Bregenz Festival Hall, the Frauenfeld Military Training Area Casino and the Seekarhaus in the Obertauern–Hundsfeldmoor nature and European conservation area. The Swiss Ornithological Institute in Sempach highlighted the Frauenfeld project as an exemplary implementation in the 2020/6 issue of its publication Bird-Friendly Building with Glass. Samples are currently undergoing flight tunnel testing at the American Bird Conservancy (ABC). Results are not yet available.
A second exhibit, for which a patent application has been filed, investigates whether different sizes, spike shapes, rotational orientations and positions can additionally create a spatially perceived hazard zone. Scientific indications supporting this approach can be found in studies by Cavoto and Cook (2006) on monocular depth perception in pigeons, Eckmeier et al. (2008/2013) on motion parallax in zebra finches, and Endler et al. (2010) on size-distance arrangements in bowerbirds. Whether these mechanisms can further enhance protection against bird collisions remains an open question and is the subject of ongoing research.
Serviceability: Safety throughout the entire service life
In this test, an all-glass railing is subjected to cyclic loading of 1 kN/m along the upper edge of the glass. After each unloading cycle, the system must reliably return to its original position. High-quality systems are characterised by maintaining their essential performance characteristics not only during initial testing but throughout their entire service life.
Even during installation, wedges, clamping mechanisms and profile deformations can introduce additional stresses, referred to as the Installation Fixation Load Case (IFL). During use, the system is subjected to thousands of load cycles, creep and relaxation, as well as the ageing and embrittlement of rubber and plastic components. Temperature fluctuations, UV radiation, water, ice, freeze-thaw cycles, dust, sand, particle accumulation and biofilm formation can further affect clamping forces, friction and the system's ability to return to its original position.
As a result, preload, contact conditions and ultimately the structural behaviour of the system may change without immediate glass breakage. Load-bearing capacity in the as-new condition alone is therefore not sufficient proof of long-term serviceability.
Our commitment to greater safety: For everyone who considers safety in glass construction a priority, the ability to return to the original position, cyclic loading and the installation fixation load case, as well as ageing and environmental influences, must form part of comprehensive system testing. What ultimately matters is that the system's performance characteristics are maintained under real-life conditions throughout its service life – ensuring safe glass railings in the long term.
