4
Explosion-Proof
Refrigerators and Freezers
Overview
Conventional refrigerators and freezers are not suitable for storing flammable
materials. Such units have components in their electrical and refrigeration
systems that can trigger explosions of flammable air-vapor mixtures inside the
unit and/or in the immediate surrounding area.
The Authority having Jurisdiction (AHJ) determines if work areas are
designated as a hazardous location with respect to the presence of flammable
gases or vapors. Such locations are defined in (National Fire Protection
Agency) NFPA 70 Articles 500-501 and OSHA 29 CFR1910.307. Some of
these classified areas are expected to experience concentrations of flammable
gases and/or vapors at or above their lower flammability limits for extended
periods of time.
The construction of our explosion-proof units has been evaluated by
Underwriters Laboratories (UL)
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are suitable for use in classified areas
requiring Class I, Groups C and D* protected equipment. The electrical
components such as thermostats, wiring, splices, relays and compressor
motors on explosion-proof units are safely housed within explosion-proof
enclosures and conduit. Compressor surface temperatures have been
evaluated and determined to remain below the flash point of materials found in
Class I, Groups C and D. All models have heavy-gauge, rigid, steel
construction with a durable enamel finish. Interiors have epoxy coated steel
construction. Each unit is insulated throughout for energy-efficient operation.
These units are ideal for storing ethyl ether, acetone, alcohol, benzene,
gasoline, hexane, lacquer solvent vapors, naphtha, along with many other
potentially hazardous materials.
WARNING
:
For FMS and EXP units where flammable materials are stored in
the cooling chamber, the cooling chamber is considered a Class I Div1 or Class
I Zone 1 hazardous location. Any monitoring devices placed in the cooling
chamber must have an intrinsically safe rating from an appropriate certification
body, such as UL, CSA, FM etc. (this includes battery or solar powered
devices).
Thermocouples for building monitoring systems must be wired through an
electrical barrier designed to provide isolation against voltage and current
spikes, which could cause a spark resulting in fire or explosion. It is the end
user's responsibility to meet these requirements.
Thermo Fisher Scientific
cannot assist with the selection of devices, recommend, approve or design any
device or monitoring circuit.
*The notation Class 1, Groups C and D is an accepted abbreviation for Class 1
Div 1, Groups C and D; Class I Zone 1 Group IIB.
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20xxxxTSV models are not evaluated or certified by UL.
