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Occupancy Determination: H-2 or H-3, Closed v. Open System

TheFirstRobyn

Registered User
Joined
Feb 20, 2024
Messages
3
Location
Topeka, KS
Hi All

Trying to make a determination on the building occupancy of structural metal painting facility. The differentiation between H-2 and H3 includes descriptions of either a closed or open system. I want to assume the system being used is closed (seems pretty closed to me) but I wondered if I might get some consensus from others with more experience. We've never done an H occupancy in our office.

The system being used is a Voortman VP. Additionally, there will be a smaller room with a pre-fabricated automotive paint booth in it. Not sure the exact model.

Please and thank you.
 
IBC definitions:

CLOSED SYSTEM. The use of a solid or liquid hazardous
material involving a closed vessel or system that remains
closed during normal operations where vapors emitted by the
product are not liberated outside of the vessel or system and the
product is not exposed to the atmosphere during normal operations;
and all uses of compressed gases. Examples of closed
systems for solids and liquids include product conveyed
through a piping system into a closed vessel, system or piece of
equipment.

OPEN SYSTEM. The use of a solid or liquid hazardous
material involving a vessel or system that is continuously open
to the atmosphere during normal operations and where vapors
are liberated, or the product is exposed to the atmosphere
during normal operations. Examples of open systems for solids
and liquids include dispensing from or into open beakers or
containers, dip tank and plating tank operations.

The following ICC commentary follows the definition of "Closed System," and the definition of "Open System" refers back to it:

The difference between a closed system and an open
system is whether the hazardous material involved in
the process is exposed to the atmosphere. While not
specific in the definition, certain gases are also
allowed in closed systems, as indicated in Tables
307.7(1) and 307.7(2). Materials in closed or open systems
are assumed to be “in use” as opposed to “in
storage.” Gases are always assumed to be in closed
systems, since they would be immediately dispersed
in an open system if exposed to the atmosphere without
some means of containment (see the definition of
“Open system”).

IMHO, there's no way that Voortman system is a closed system.

xx
 
The differentiation between H-2 and H-3 goes far beyond 'open' or 'closed.' You have quantities and hazardous materials classifications to deal with.
Its pretty complicated and generally takes reading through all of the MSDS sheets for the chemicals being stored and used on site to make the determination, taking into consideration their toxicity, flammability and hazardous ratings.
IIRC paint is particularly flammable.
 
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