UL Question Corner: New Understanding HazLoc App

I rarely deal with hazardous location installations and find it difficult to grasp the concepts each time I have to inspect one.  Does UL have any information that will help to understand hazardous location installations?

Yes, UL has several tools available to de-mystify hazardous locations.  UL has been certifying hazardous location equipment for over 100 years, and has launched a smart device application explaining the different hazardous locations classification systems, the Class and Division as well as Zone Systems. The smart device app, titled “Understanding HazLoc,” covers hazardous location principles such as explosive atmospheres, likelihood of presence, ignition-related properties, temperature classifications, protection techniques and standards.  It also includes a “Find Your Standard” feature that tells users which standard applies to an installation for the United States, Canada, Australia, Brazil, China, Europe, India, Japan, Korea, New Zealand, Russia and South Africa.

In addition, the app explains markings, IP (ingress protection) and enclosure type ratings and offers links to where users can find haz loc training from UL as well as a link to verify UL certifications (Listings).

The app is free and available for download from the Apple App store or Google Play. Please search for “UL Haz Loc” to access it.

UL also offers complimentary hazardous location educational posters or binder inserts explaining the Class and Division, and Zone Systems.  To request these, please go to www.ul.com/hazloc .


Last year I saw UL Listed dual function arc fault circuit interrupter (AFCI) and ground fault circuit interrupter (GFCI) circuit breakers introduced into the market place.  Are there any UL Listed dual function GFCI and OBC AFCI receptacles?

Yes, there are dual function GFCI and OBC AFCI receptacles.  UL certifies (Lists) these dual function receptacles under the product category Ground-fault Circuit Interrupters and Arc-fault Circuit Interrupters, Outlet Branch Circuit Type (KCXX).

This category covers Class A ground-fault circuit interrupters (GFCI) that provide protection when the ground fault current has a value in the range of 4 through 6 mA and outlet branch circuit arc-fault circuit interrupters (OBC AFCI) that provide protection to downstream branch-circuit wiring, cord sets and power-supply cords against the unwanted effects of arcing. These devices also provide series arc fault protection to upstream branch-circuit wiring. These devices have feed-through connections for wiring and protection to downstream receptacles.  These dual function devices are intended for use where GFCI and/or OBC AFCI protection device is required by ANSI/NFPA 70, National Electrical Code (NEC).

See the UL Guide information and certifications (Listings) on UL Product Spec at www.ul.com/productspec and enter KCXX at the UL category code search field.  As of this writing, UL has certified (Listed) at least one manufacturer’s products in this category.

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