These requirements cover electrically- and electronically-operated amplifiers that provide speech communication and distinctive sounds in conjunction with fire protective signaling systems for indoor location in accordance with the following standards: a) National Electrical Code, NFPA 70. b) National Fire Alarm Code, NFPA 72. These requirements do not cover amplifiers for use in hazardous locations, as defined in the National Electrical Code, NFPA 70. These requirements do not cover commercial equipment for institutional and industrial use or theater equipment. Commercial sound equipment is covered by the Standard for Commercial Audio Equipment, UL 813. These requirements do not include determination of compliance with regulations of the Federal Communications Commission (FCC). Should products covered by these requirements be required to comply with FCC regulations, a report of verification from the manufacturer is required as evidence of such compliance. A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire, electric shock, or injury to persons shall be evaluated using the appropriate additional component and end-product requirements to determine that the level of safety as originally anticipated by the intent of this standard is maintained. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this standard shall not be judged to comply with this standard. Where appropriate, revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard.