Which zones are classified in Article 505?

Article 505 of the National Electrical Code (NEC) pertains to locations that are classified as hazardous due to the presence of flammable gases or vapors. In this article, zones are categorized specifically by the potential for explosive atmospheres, with Zone 0, Zone 1, and Zone 2 identified as the critical categories.

Zone 0 refers to areas where an explosive gas atmosphere is present continuously or for long periods. Zone 1 is where such atmospheres are likely to occur in normal operation, while Zone 2 is where these atmospheres are not expected to occur in normal operation and, if they do occur, they will only exist for a short time. This classification system helps to determine the appropriate electrical equipment and installation methods required to ensure safety in environments where flammable substances are handled or stored.

The classification not only facilitates compliance with safety regulations but also aids in minimizing the risks associated with electrical installations in these zones. Understanding these zone designs is crucial for electricians and engineers working in hazardous locations, as selecting the correct equipment significantly impacts overall safety and functionality in these environments.