This pocket guide provides an overview of the requirements for the installation of cables concealed in structures in accordance with regulation group 522. 6 of BS 7671:2018+A2:2022 (IET Wiring Regulations 18th Edition). According to the NEC (National Electrical Code), all wire splices and electrical connections must be enclosed within an approved electrical junction box to ensure safety, accessibility, and code compliance. Every state has adopted some version of the NEC, though the specific edition in force and any local amendments depend on your jurisdiction's. NEC Article 314 establishes requirements for the installation and use of electrical boxes, conduit bodies, fittings, and handhole enclosures. A conduit body is a removable-cover section of a conduit system that provides access at junctions or termination points. Non‑compliance risks safety or code violations. Junction boxes may be small, but they're critical for electrical safety.