Explosion proof refrigerators and freezers

A hazardous location is any area where flammable gases or vapors, combustible dust, or ignitable fibers may be present in sufficient concentrations to create a risk of fire or explosion. Standard refrigeration equipment contains electrical components that can spark during normal operation, making it unsafe in these environments. The National Electrical Code (NEC) classifies these locations by the type of hazard and the likelihood of exposure, and equipment used within them must be specifically designed to eliminate both internal and external ignition sources. A purpose-built explosion proof refrigerator or freezer provides safe cold storage where conventional units simply cannot be used.

The term “explosion proof” is widely used in our industry, but it has a precise technical meaning. According to Article 100 of the National Electrical Code, explosion proof apparatus must be enclosed in a case capable of withstanding an internal explosion and preventing sparks, flashes, or internal gases from igniting the surrounding atmosphere. In practice, our explosion proof walk in units are built without internal electrical components and feature sealed, spark-proof construction both inside and out, so they cannot serve as an ignition source for hazardous gases or vapors in the surrounding area. All units comply with Chapter 5 of the National Electric Code.

Our explosion proof walk in units are built without any internal electrical components. All exterior electrical components, including lights, fans, thermostats, and compressors, are specifically selected or modified to meet the applicable hazardous location classification and are sealed to NFPA and OSHA guidelines. The seamless one-piece fiberglass construction provides a corrosion-resistant, airtight enclosure that prevents the escape or entry of hazardous vapors. Each unit is also engineered to withstand the pressures generated by an internal explosion, which is a core requirement of the NEC’s definition of explosion proof apparatus.

Both types share a spark-free interior design, but the key distinction is how each unit handles the environment outside the unit itself. A flammable storage refrigerator is built to prevent ignition of volatile substances stored inside the unit, making it appropriate for standard lab or storage settings where the surrounding area is not itself flammable. An explosion proof refrigerator goes further by also eliminating sparking components on the exterior of the unit, so it cannot ignite hazardous vapors or gases present in the surrounding atmosphere. If your workspace contains a flammable atmosphere, such as a Class I, Division 1 or 2 environment, an explosion proof unit is required. A flammable storage unit alone is not sufficient for those conditions.

Hazardous locations in North America are classified by Class, Division, and Zone. Classes describe the type of hazard present: Class I covers flammable gases or vapors, Class II covers combustible or conductive dusts, and Class III covers ignitable fibers or flyings. Divisions describe the likelihood that those hazards are present in ignitable concentrations, with Division 1 meaning ignitable concentrations exist under normal operating conditions and Division 2 meaning they are present only under abnormal conditions such as equipment failure.

Our explosion proof walk in units are rated for Class I, II, and III, Division 1 and 2, as well as Zones 0, 1, and 2, covering a wide range of industrial hazardous location requirements.

Any operation that requires cold storage in or adjacent to a classified hazardous location needs an explosion proof unit rather than standard refrigeration. Typical industries include petroleum refining, chemical manufacturing, pharmaceutical production, spray-coating or finishing operations, grain milling, and any facility where flammable solvents, gases, or combustible dusts are handled or processed.

If your site has been classified under NFPA or NEC hazardous location standards, our team can help you identify the correct Class, Division, and Zone rating for your specific application and configure a unit that meets those requirements.

In addition to the standard explosion proof construction, our units can be configured with a gas detection system (LEL monitor) to provide early warning of hazardous vapor concentrations before they reach ignitable levels. We also offer an integrated 500-gallon containment sump for operations that require spill containment as part of their environmental or regulatory compliance plan. All units can be fully customized to your site’s specific hazard classification, layout, temperature requirements.

Our explosion proof walk in units are designed and built to comply with Chapter 5 of the National Electrical Code, which governs wiring and equipment in classified hazardous locations. NFPA model codes form the basis for how hazardous locations are defined and enforced, and OSHA requirements apply to workplace safety in environments where flammable or ignitable materials are present. All explosion proof components are listed, labeled, and sealed to match the applicable area classification, and units are fully assembled and tested at our facility before delivery.