Understanding Class 1 Division 2 HVAC

class 1 division 2

Understanding Class 1 Division 2 HVAC

Understanding Class 1 Division 2 HVAC

Chances are if you’re not a manufacturer, “Explosion Proofing” to Class 1 Division 2 standards is a term that sounds overwhelming and maybe a little dangerous. In this article, we’ll strip off the engineering jargon and help you understand what it is, how it fits in with other explosion proof classifications, where to find them and even some prices for equipment. (Pricing is at the bottom of the page)


“Explosion Proof” is a term for HVAC equipment built for Hazardous or classified environments. These air conditioners are not bombproof; instead, an explosion proof air conditioner is one that’s constructed or modified so it does not become an ignition source through arch or spark in a hazardous location where gases, dust or fibers are or may be present in combustible concentrations.

Technically speaking, the Class 1 Division 2 classification, also know with a roman numeral Class i division 2, identifies a specific hazardous location in which volatile flammable liquids, gases or vapors, or combustible vapors are:


  1. Generally confined within closed containers or closed systems, but only escape in case of accident or abnormal operating of equipment.
  2. Prevented by positive mechanical ventilation.
  3. Adjacent to a division 1 location.

In other words, under ordinary circumstances, ignitable flammable gas or vapors will not exist in this space unless there are abnormal circumstances, like a failure of a system. Most of our customers requesting Class 1 Division 2 air conditioners use them in storage settings. It’s the most common form of explosion proofing we’re asked perform.


class 1 division 2


It’s the responsibility of those who understand the dangers of the
products and manufacturing environments, such as the fire marshal, plant facility engineer, or insurance underwriter, to identify the classification of a hazardous area. Many items that are generally regarded as harmless such as grains, metals, and dusts become a fire or explosion hazard when particles are less than 500 microns and dispersed in the air.

What makes Class 1 Division 2 different from other Classifications


To understand how Class 1 Div 2 units are different from other specifications, we need to know the rating system. North America specifies hazardous locations in classes, divisions, and groups. “Classes” define the general nature of the hazardous material in the surrounding atmosphere in three distinctions. Gasses (class I), Dusts (class II), and fibers (class III). Divisions represent the probability of the hazardous material in quantities sufficient for ignition. Division 1 is a high probability in normal conditions and division 2 being a low probability in abnormal conditions. Class 1 (Gasses) Division 2 (low probability in normal conditions). To learn more about how the explosion proof classifications visit our page “What is an Explosion Proof Air Conditioner.


Other Posts on North American hazardous locations
Class I Division 1
Class II Division 1
Class II Division 2
Class III Division 1


From a manufacturers perspective, Class 1 Division 2 has more flexibility than a Class 1 Division 1. Some items like heaters will still need a Class 1 Division 1 rating, but many general-purpose motors can be used in division 2 environments with little or no modifications. Explosion proof enclosures are not mandatory if criteria are met in preventing arching sparking. Fire retardant braided sleeve or rigid and intermediate metal conduit with listed threadless fittings are fine to use as well.

Can I use Class 1 Division 1 for C1D2

Equipment manufactured for Class I Division 1 locations may be installed in Class I Division 2 location of the same class, group, and temperature class. Although, it’s generally not advised as the rating ads extra cost to the equipment. To avoid the added expense of classified location equipment, it’s recommended to locate as much of the electrical equipment as possible to outside the classified hazardous location. Fortunately, air conditioners come in two separate sections…an Indoor (Evaporator) section and outdoor (condenser) section. These different parts of the unit can be classified differently to minimize costs. For example, If the inside of your structure is classified, a wall mounted unit would only need its evaporator (indoor) section classified because it’s the only part of the unit that will come on contact with the interior space.

Class 1 Division 2 HVAC For Sale, Rent, and Order

Your options for C1D2 equipment is as varied as your options for Air Conditioners. We can modify and certify any existing equipment to the standards you need. Most of our customers utilize Window Units (0.5 Tons – 3.0 Tons) Wall Mounted Bard or Marvair equipment (1.0-6.0 Tons) or request a custom build for larger sizes.

Pricing on Window Units

Pricing for pricing on Wall or Custom units please reach out to us at (844) 925-5668 or [email protected] do discuss your project in more detail.

XP Climate Controls is a custom HVAC manufacturer that builds industrial air conditioners to exacting explosion proof and hazardous location specifications.

HVAC equipment comes in many shapes, sizes, functions, and classifications so if we don’t have your exact unit in stock, we will build it for you.

We currently stock Class 1 Division 2 window unit or have several rental C1D2 rental units available to hold you over until we can build your unit.