Codes, Standards, and Project Documentation
Know the hierarchy before you answer
NFPA 72 (National Fire Alarm and Signaling Code) governs system performance, installation, testing, and maintenance. NFPA 70 (NEC), mainly Article 760, governs wiring methods and power sources. NFPA 101 and the locally adopted building code establish when a system is required and which features it needs. Manufacturer's published installation instructions are part of the product listing (UL 864); a listed device installed contrary to its instructions is not a compliant installation. Local AHJ amendments override the model codes.
Documentation is tested heavily because it preserves design intent. Distinguish design/shop drawings (device locations, riser, wiring) from the sequence-of-operations matrix (what each input causes), battery and voltage-drop calculations, and the Record of Completion (NFPA 72 Chapter 7), which documents that the system was installed per plans and tested. The Record of Inspection and Testing is a separate ITM document.
Traps: "listed" vs "approved" (listing is a laboratory finding; approval belongs to the AHJ); confusing a code with a standard; asking which document controls conduit fill (NEC Chapter 9) vs detector spacing (NFPA 72); and assuming as-built drawings replace the Record of Completion. When documents conflict, the more stringent requirement generally governs, and the AHJ decides.
Worked example: if plans show a detector spacing that conflicts with NFPA 72, you do not simply "build the plans" - submit an RFI and resolve it before installation. Rule of thumb: the code says what must be achieved; the listing says how the device must be installed.