Which of the following is a common material used for marine wiring insulation?

Polyvinyl Chloride (PVC) is commonly used for marine wiring insulation due to its excellent balance of flexibility, durability, and resistance to moisture, chemicals, and UV radiation. In the marine environment, where exposure to harsh weather conditions, saltwater, and potential abrasion is prevalent, PVC provides a reliable insulating property that protects the wiring from damage and electrical faults.

Additionally, PVC insulation has good fire-retardant qualities and is less likely to support combustion, which is a critical factor in marine applications where safety is a top priority. Its lightweight nature also contributes to its usage in wiring, making installations easier and more efficient without adding excessive weight to the vessel.

Other materials like rubber and polyethylene have specific benefits, but PVC's overall properties make it the preferred choice for marine wiring insulation, ensuring both safety and longevity in challenging conditions. Steel, while strong, is not suitable for insulation purposes due to its conductivity and susceptibility to corrosion in a marine environment.