5.1 Photovoltaic modules are electrical dc sources. dc sources have unique considerations with regards to arc formation and interruption, as once formed, the arc is not automatically interrupted by an alternating current. Solar modules are energized whenever modules in the string are illuminated by sunlight, or during fault conditions.

5.2 With the rapid increase in the number of photovoltaic system installations, this guide attempts to increase awareness of methods to reduce the risk of fire from photovoltaic systems.

5.3 This guide is intended for use by module manufacturers, panel assemblers, system designers, installers, and specifiers.

5.4 This guide may be used to specify minimum requirements. It is not intended to capture all conditions or scenarios which could result in a fire.

1.1 This guide describes basic principles of photovoltaic module design, panel assembly, and system installation to reduce the risk of fire originating from the photovoltaic source circuit.

1.2 This guide is not intended to cover all scenarios which could lead to fire. It is intended to provide an assembly of generally-accepted practices.

1.3 This guide is intended for systems which contain photovoltaic modules and panels as dc source circuits, although the recommended practices may also apply to systems utilizing ac modules.

1.4 This guide does not cover fire suppression in the event of a fire involving a photovoltaic module or system.

1.5 This guide does not cover fire emanating from other sources.

1.6 This guide does not cover mechanical, structural, electrical, or other considerations key to photovoltaic module and system design and installation.

1.7 This guide does not cover disposal of modules damaged by a fire, or other material hazards related to such modules.

1.8 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.