Q: Can indoor optical cables be directly used outdoors as a substitute? What are the risks? A: Absolutely prohibited. Fiber optic cables are categorized based on their deployment environment: indoor fiber optic cables and outdoor fiber optic cables. Each type is designed with specific features to ensure optimal performance under varying conditions. UV Exposure: Prolonged sunlight degrades standard plastic jackets, making them brittle. These are the outdoor fiber optic cables you see strung along telephone poles (aerial), installed inside an underground duct, or even. Outdoor fiber optic cable is a type of communication cable specifically designed for harsh outdoor environments.