True or False: Non-metallic boxes are only to be used with cable wiring methods that utilize non-metallic sheathed flexible cords and non-metallic raceways.

The statement is true because non-metallic boxes are specifically designed to be used with non-metallic wiring methods. These boxes are intended for use with non-metallic sheathed cable, which includes flexible cords and certain types of raceways. This compatibility ensures that the electrical connections are safe and effective while preventing issues that could arise from using non-metallic boxes with metal conduits or wiring methods that require grounding, which is essential for metal boxes.

Using non-metallic boxes in conjunction with non-metallic cables helps in maintaining insulation and reducing the risk of electrical shock. Additionally, these materials can be more resistant to corrosion compared to their metallic counterparts and are generally lighter and easier to work with.

The other options create some ambiguity, as "false," "sometimes," and "conditional" suggest that there could be exceptions or alternative applications for non-metallic boxes that do not align with the standard practices outlined in electrical codes and guidelines. Therefore, affirming that non-metallic boxes are indeed limited to specific wiring methods reflects a clear understanding of their intended use in electrical installations.