The lack of marked anti-corrosion layer on cable trays and absence of standardized text descriptions is another common issue in engineering design. This shortcoming has resulted in real-world ramifications. For example, during a project in Indonesia that my country was contracted to undertake, the steel cable tray's surface anti-corrosion treatment hadn't undergone salt spray tests. Consequently, the bridge corroded significantly right after completion, necessitating replacement. The anti-corrosion layers on cable trays include hot-dip galvanizing, galvanized nickel, cold galvanizing, powder electrostatic spraying, and more. According to manufacturer's information, the hot-dip galvanizing process guarantees a service life of not less than 40 years, making it suitable for harsh outdoor corrosive environments. On the other hand, galvanized nickel will last for at least 30 years with a high cost and suitable for heavy outdoor corrosive conditions. Meanwhile, cold galvanizing will last for 12 years minimum, ideal for mild outdoor corrosive environments at an average cost. Lastly, the powder electrostatic spraying process has a life of 12 years minimum and is appropriate for indoor dry environments at room temperature, being moderately priced. The designer must choose the cable tray's surface anti-corrosion layer that matches the engineering environmental conditions, and explicitly state the selection in the design documents.
