LABO VEN S.IN S.7-18.wpd
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07/18
3-3.3
Do not store material on top of oven. The oven is not designed to carry exterior
loads. Also, material may get hot, ignite and cause a fire.
3-3.4
The oven doors have spring loaded latches which will allow the doors to open if
pressure develops in the oven. The door travel must not be restricted and should
face away from main aisles, work areas and automatic sprinkler risers, feeds and
cross mains.
3-4
VENTILATION
3-4.1
W here ovens are located in basements or enclosed areas, sufficient room
ventilation shall be supplied to prevent the hazardous accumulation of vapors from
processing.
3-4.2
Fresh air inlets and exhaust outlets must never be restricted.
3-5
EXHAUST DUCTW ORK
3-5.1
The oven has vent holes in the top. If the oven vented air is to be collected and
ducted from the area, it must be in accordance with local codes and requirements.
Exhaust gas temperature is the same as internal oven temperature. Caution must
be taken to protect combustible building materials from coming in contact with the
hot exhaust stack.
3-5.2
W herever oven ducts or stacks pass through combustible walls, floors or roof, non-
combustible insulation or clearance, or both, shall be provided to prevent
combustible surface temperatures from exceeding 160
E
F (71
E
C).
3-5.3
W here ducts pass through non-combustible walls, floors or partitions, the space
around the duct shall be sealed with non-combustible material to maintain the fire
resistance rating of the barrier. Ducts that pass through fire walls should be
avoided.
3-5.4
Ducts shall be constructed entirely of sheet steel or other non-combustible material
capable of meeting the intended installation and conditions of service. The
installation shall be of adequate strength and rigidity and shall be protected where
subject to physical damage.
3-5.5
Ducts handling fumes that leave a combustible deposit shall be provided with
clean-out doors and such doors should be equipped with tight fitting doors or
covers. It is important that ovens and ducts be kept clean if they are subjected to a
build-up of flammable deposits of dust or other combustible debris. The build-up of
condensed vapors or combustible debris is a major cause of fires. Frequency of
cleaning should be based on never allowing build-up to exceed 1/8" thickness in
any location.
3-5.6
No portions of the building shall be used as an integral part of the duct.
3-5.7
Ducts handling combustible solids shall be designed to minimize the accumulation
of solids within the ducts.
3-5.8
Exhaust ducts that will contain combustible deposits of any type require automatic
sprinklers.
3-5.9
Clearance between m etal ducts and stored combustible material should be at least
2-1/2 feet. Guards should be installed to assure this clearance.
