Zones are classified by the by the International Electrochemical Commission (IEC) in Europe, Asia, Australia, Africa and other regions or the National Fire Protection Association (NFPA) National Electric Code (NEC) in the United States Class I Division 1 hazardous areas are locations that are defined within the NEC Handbook, articles 500, 501, 502, 503, 505, and 506.  Class I locations are those in which flammable gases or vapors are present in the air in quantities sufficient to produce explosive or ignitable mixtures (NEC 501).  Division 1 is a subset of Class I and is classified as an area where the explosive or flammable gases, vapors or liquids mentioned above can exist under normal, everyday operating conditions. One characteristic of Zone 2 areas is when ignitable concentrations of flammable gases or vapors are not normally present but could be present in certain cases that are clarified in the NEC standards.  Zones are also classified by ATEX 1999/92/EC Directive based on the frequency and duration of the occurrence of the explosive atmosphere.  Zone 2, according to ATEX 1992/92/EC Directive, is when an explosive atmosphere is likely to occur infrequently or for short periods of time. Explosion-proof floor scales are approved for Zone 1/21 Division 1 and Zone 2/22 Division 2 based on their ability to achieve the level of safety required in the above defined environments. For more information on selecting explosion-proof floor scales or explosion-proof area classification, download the
Hazardous Area Competence Guide.