6 Environmental control enclosures and skids made of metal or composite materials, namely, modular structures used for environmental protection, separation and containment; modular buildings; Factory assembled metal or composite buildings, namely, equipment shelters for the protection of controls, relays, junctions, transformers, power distribution equipment, switchgear, motor controls and monitoring equipment primarily used in the electric utility and electric power generation and distribution industries; Preassembled modular buildings for the integration and protection of high value electrical and mechanical equipment