SECTION 4 – SYSTEM DESIGN
UL EX3470 ULC EX3470
2014-SEP-01 REV. 11 PAGE 4-53
R-102 Restaurant Fire Suppression Manual
OVERLAPPING NOZZLE COVERAGE
Overlapping Coverage – Option 1
For each group of protected appliances under a common
hood(s), the overlapping nozzles must be located from right
to left so that each end nozzle is located a maximum of 6 in.
(152 mm) inside the outside edge of the cooking hazard of each
end appliance, and the inside overlapping nozzles must be
located between the two end nozzles at a maximum spacing of
12 in. (304 mm).
Hazard Zone
The hazard zone is defined as a theoretical, flat and level, rect
-
angular surface, that includes all of the cooking hazards of the
protected appliances under a common hood(s). The purpose of
the hazard zone is to provide a means of locating the appliances
and the overlapping nozzles, as well as aiming the overlapping
nozzles. The hazard zone measures 28 in. (711 mm) deep by
the length of the cooking hazard(s). The centerline of the hazard
zone must bisect the 28 in. (711 mm) depth (from front to back)
and run from right-to-left for the full width of the hazard zone.
Overlapping Nozzle Appliance Protection
Overlapping Nozzle Appliance Protection is defined as protec
-
tion of cooking appliances by nozzles spaced uniformly at
uniform elevations under a common hood(s). Overlapping
protection of appliances is continuous for the full length of the
hood or divided when group(s) of protected appliances are
separated by counters or appliances not requiring protection.
Full hood continuous protection
is defined as overlapping
nozzle appliance protection that covers the appliance line-up
located under the total hood length. All appliances requiring
protection are the appliances under the hood that can be an igni-
tion source of grease in the hood, grease removal device or the
duct.
Group protection
is defined as overlapping nozzle appliance
protection that protects individual hazard zones located under a
common hood. These “groups” of appliances may be separated
by appliances not requiring protection, such as steam equipment
or work tables, or by dedicated appliance protection, such as
salamander broilers.
See Figure 4-108 (full hood continuous protection) and Figure
4-109 (multiple group protection).
Dedicated Nozzle Appliance Protection
Appliance protection using dedicated nozzle coverage is defined
as protection of cooking appliances with enclosed cooking
hazards, such as upright broilers, which cannot be protected
with overlapping nozzles and therefore must be protected with
nozzles dedicated to the appliance.
General Design Limitations
• Maximum depth of zone is 28 in. (711 mm).
• The 245 nozzle is the only approved nozzle for overlapping
(zone) protection.
• Nozzle must be located 0 in. to 6 in. (0 mm to 152 mm) forward
of zone centerline, aimed back at the zone centerline.
• Nozzles must be spaced a maximum of 6 in. (152 mm) from
each end of hazard and then a maximum of 12 in. (304 mm)
on center for the remaining overlapping nozzles until the
complete hazard is covered.
• For appliance hazard surfaces
with listed protection exceed-
ing the standard hazard zone of 28 in. (711 mm) in depth, the
hazard surface(s) must be aligned with the back edge of the
hazard zone, with the front edge overhanging the front edge
of the zone. See Appliance Chart, Table 4-1.
• For appliance hazard surfaces that
exceed the listed protec-
tion
sizes, multiple zones must be utilized. Align entire hazard
surface area within the multiple zones.
• All hood, duct, individual appliance, piping, and flow limitations
are as specified in the R-102 Design, Installation, Recharge
and Maintenance Manual (Part No. 418087).
• All appliance protection currently listed in the R-102 Design
Manual (Part No. 418087) is also approved protection. Zone
protection can be considered optional protection.
TABLE 4-1
Overlapping Nozzle Coverage (Zone Protection)
Appliance Type
Maximum Cooking Hazard
Fryer
34 in. (863 mm) Deep x 5.8 ft
2
(0.5 m
2
)
Griddle
30 in. (762 mm) Deep x Unlimited Length
Range
28 in. (711 mm) Deep x Unlimited Length
Wok, Maximum
30 in. (762 mm) Diameter x 8 in.
(203 mm) Deep
Wok, Minimum
11 in. (279 mm) Diameter x 3 in.
(76 mm) Deep
Braising Pan/Tilt
34 in. (863 mm) Deep x Unlimited
Skillet*
Length
Lava Rock
32 in. (812 mm) Deep x Unlimited
Char-Broiler
Length
Charcoal Broiler
32 in. (813 mm) Deep x Unlimited Length
(4 in. (102 mm) Maximum Fuel Depth)
Mesquite Wood
32 in. (812 mm) Deep x Unlimited Length
Broiler
(12 in. (304 mm) Maximum Fuel Depth)
Gas Radiant
36 in. (914 mm) Deep x Unlimited
Char-Broiler
Length
Electric Char-Broiler 34 in. (863 mm) Deep x 20 in. (508 mm)
* See Figure 4-105 for nozzle location
FIGURE 4-105
COVER MUST NOT
INTERFERE WITH
EDGE OF
DISCHARGE
PATTERN
0-6 IN. (0-152 mm)
40-45 IN.
(1016-1143 mm)
ZONE CENTER LINE
ZONE
006927