Type NM-B (Non-metallic sheathed cable) has a broad range of usage as defined in Article 334 of the National Electrical Code (NEC). Type NM-B cable is commonly used for residential fixtures, switches, and loads rated for at least 90°C. Type NM-B ampacity limitation shall be in accordance with the 60°C conductor temperature rating, as specified in the National Electrical Code. Type NM-B is rated for 600 volts for both exposed and concealed work in normally dry locations. Type NM-B may be installed or fished in air voids and joints and in masonry block or tile walls where such walls are not exposed to, nor subject to, excessive moisture or dampness.