Testing of Electrical Equipment for Use in Hazardous Locations

The necessity of employing special electrical equipment in hazardous areas where gases, vapors, and dusts of an explosive nature are handled or encountered is explored. Tests conducted on such equipment to demonstrate that it can be operated safely in such hazardous areas are described. The general procedure for submitting the equipment to Underwriters´ Laboratories, Inc., for the investigations is described as well as the follow-up service conducted at the manufacturer´s plant on the production devices. Some of the questions which arise with respect to possible self-certification by a manufacturer are also discussed.