These requirements cover the construction and operation of halogenated agent fire extinguishing system units intended to be installed, inspected, tested, and maintained in accordance with the Standard for Halon 1301 Fir e Extinguishing Systems, NFPA 12A and with the Standard for Halon 1211 Fire Extinguishing Systems, NFPA 12B.

These requirements also cover halogenated automatic extinguisher units that do not have a manual means of operation, and are intended to be used in accordance with the manufacturer's installation instructions. Automati c extinguisher units are not intended:

a) For use as a general substitute for preengineered or engineered halon extinguishing system units; or

b) For protection of fire risks larger than those specified in the manufacturer's instructions for a single unit by using multiple units.

A product that contains features, characteristics, components, materials, or systems new or different from those in use when the Standard was developed, 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 as determined necessary to maintain the level of safety for the user of the product as originally anticipated by the intent of this Standard.