- Heavy-Duty Galvanizing: Specify a thicker zinc coating (e., G235) for increased sacrificial material. This protective layer ensures the longevity and safety of cable trays, making them more resilient in challenging environments. Why Choose Hot-Dip. Hot dipped galvanized cable tray with a 65-micron coating is well-suited for outdoor installations where the trunking is exposed to weather elements such as rain, humidity, and UV radiation. Hot-Dip Galvanizing is an anti-corrosion treatment process in which steel is immersed in molten zinc at about. This white paper compares the High Resistance (HR) and Hot-Dip Galvanising (HDG) solutions and highlights the new High Resistance range, ZnAl wiremesh, ZnMg metal cable trays and accessories and ZnNi screws and bolts. However, exposure to harsh environments can lead to corrosion, compromising their structural integrity and safety.