Class III Hazardous Areas

The National Electrical Code, or NEC, classifies hazardous areas into three different categories; Class I, Class II, and Class III.  To use equipment in or around these types of areas, caution has to be taken in order to not cause an explosion or fire.  In the U.S., the Underwriter’s Laboratory, UL, can certify products that can be used safely in these hazardous areas.  EXAIR received our UL Classification for our new product line; the HazLoc Cabinet Cooler Systems.  Under certain guidelines, the HazLoc Cabinet Coolers can be used in Class I for gases and vapors, Class II for flammable dust, and Class III for ignitable fibers and flyings.  In this blog, I will be discussing the Class III classified area.

For a fire or an explosion to occur, we need three things as described in the fire triangle; oxygen, fuel, and an ignition source.  For Class III areas, that fuel is a build-up of material like fabric lint and fine wood shavings.  These small fibers can float and collect on equipment in the surrounding areas.  This collection of material can easily ignite and cause a fire from a spark or a heat source, like kindling.  These fibrous materials and flyings are not explosive, but as a collection, they are a fire hazard; the reason for the Class III designation.  This newest hazardous classification is generally located within the textile and woodworking industries.

The ignition source (the second leg of the fire triangle) is generally from electrical equipment, heat, and static.  Arcs and sparks from motors, contactors, and switches can easily ignite Class III materials; as well as high temperatures from equipment.  NEC and UL segregate this hazardous location into two divisions.  Class III Division 1 is in an area where fibers/flyings are handled, manufactured, or used.  Class III Division 2 is where the fibers/flyings are stored or handled other than in the process of manufacturing.  In both divisions, it is important to protect your electrical systems from these small fibers floating in the surrounding air.

EXAIR's Hazardous Location Cabinet Cooler

The EXAIR HazLoc Cabinet Cooler Systems are designed to keep your electrical panels cool within hazardous areas like Class III because system shutdowns from electrical overheating are costly and potentially dangerous.  If you would like to discuss the details about the EXAIR HazLoc Cabinet Coolers, an Application Engineer at EXAIR will be happy to help you.

 

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

NEW From EXAIR! The Hazardous Location Cabinet Cooler – For Use In Classified Areas

EXAIR is always focused on releasing new products and improving on existing product lines, and 2018 has been no different! Earlier on this year we introduced the New Super Air Scraper as an accessory to our 2” Flat Nozzles and Safety Air Guns. Just last month, EXAIR has also introduced a new line of products to the Cabinet Cooler family: The Hazardous Location Cabinet Cooler.

hazloc_illLsr-800w

EXAIR’s Hazardous Location Cabinet Coolers are engineered for use with purged (not included) electrical enclosures. The HazLoc Cabinet Coolers are not purged and pressurized control systems and should not be relied upon nor used in place of a purged and pressurized controller. They are meant for use in conjunction with a purged and pressurized control system. These systems have been approved and tested by UL for use in the following areas:

Class I Div 1&2 – Groups A, B, C, and D

  • Class I Areas refer to the presence of flammable gases or vapors in quantities sufficient to produce explosive or ignitable mixtures. Class I Div 1 will have ignitable concentrations of flammable gases present during the course of normal operations. This is level of approval is one that differentiates the EXAIR Hazardous Location Cabinet Coolers from much of the competition. Class 1 Div 2 areas will have flammable gasses or vapors present only in the event of an accident or during unusual operating conditions.

Class II Div 1&2 – Groups E, F, and G

  • Class II areas are locations in which combustible dust may exist. The end user shall avoid installation of the device in a Class II environment where dust may be readily disturbed from the exhausts of the Hazardous Location Cabinet Cooler. Any dust formed in the vicinity of the cooler must be cleaned regularly.

Class III

  • Class III areas are locations that will have ignitable fibers or flyings present. This is common within the textile industry.

The Cabinet Cooler also carries a temperature rating of T3C, meaning it cannot be installed near any materials that could auto-ignite at temperatures in excess of 320°F. For a comprehensive list and description of all of the various Classified areas, check out the UL website.

The Hazardous Location Cabinet Cooler is available in (8) different cooling capacities ranging from 1,000 Btu/hr – 5,600 Btu/hr. The Cabinet Cooler is the best solution for protecting your sensitive electronics from heat, dirt, and moisture. With Nema 4/4X systems available, the Hazardous Location Cabinet Coolers will keep the cabinet cool without compromising the integrity of the enclosure.

If you’ve got an electrical cabinet installed within a hazardous location, fill out the Cabinet Cooler Sizing Guide and allow an EXAIR Application Engineer to determine the most suitable model for you.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@exair.com
Twitter: @EXAIR_TD