1. PRODUCT NAME
VIKING Microfast
®
Model M-4
Small Orifice
Residential Pendent Sprinkler
2. MANUFACTURER
THE VIKING CORPORATION
210 N. Industrial Park Road
Hastings, Michigan 49058, USA
Telephone: (616)
945-9501
(800) 968-9501
Fax No:
(616) 945-9599
From outside the U.S.A.:
Telephone: +1 (616) 945-9501
Fax No:
+1 (616) 945-9599
e-mail: techsvcs@vikingcorp.com
3. PRODUCT DESCRIPTION
The Viking Microfast
®
Model M-4 Small
Orifice Residential Pendent Sprinkler is
a small, high-sensitivity, glass-bulb
spray sprinkler. The sprinkler is avail-
able in several finishes, with tempera-
ture ratings to meet design require-
ments. The sprinkler is listed for use
below smooth, flat, horizontal ceilings
and ceilings with slopes up to and in-
cluding a 6/12 pitch. (26.
6°) T
he small
orifice design, with a K Factor of 4.3,
allows efficient use of available water
supplies for the hydraulically designed
fire-protection system. The small, rug-
ged, 3mm glass-bulb and special deflec-
tor combine speed of operation and ar-
eas of coverage to meet residential
sprinkler standards. During fire condi-
tions, the heat-sensitive liquid in the
glass bulb expands, causing the glass to
shatter, releasing the pip cap and seal-
ing spring assembly. The water flowing
through the sprinkler orifice strikes the
sprinkler deflector, forming a uniform
spray pattern to extinguish or control the
fire.
4. TECHNICAL DATA
See chart for approvals.
See chart for minimum water supply re-
quirements and maximum areas of
coverage.
Glass-bulb fluid temperature rated to
-
65°F (-55°C).
Rated to 175 PSI (1 207 kPa) water
working pressure.
Factory tested hydrostatically to 500 PSI
(3 448 kPa).
Spring: USA Patent No. 4,167,974
Bulb: USA Patent No. 4,796,710
Testing: USA Patent No. 4,831,870
Thread Size: 1/2" (15 mm) NPT
K Factor: 4.3 (6,2 Metric*)
*See Footnote 8 on approval chart.
SPRINKLER MATERIALS:
Frame - Brass Castings UNS-C84400
Form No. F_082095
Sprinkler 140 a
June 4, 1998
TECHNICAL DATA
Replaces sprinkler page 140 a-c, dated August 25, 1997
(updated approved finish and escutcheon lists).
APPROVED
APPROVED FINISHES APPROVED ESCUTCHEONS
TEMPERATURES
1: Brass, Bright Brass, Chrome- X: Standard surface or F-1 Adjustable
A: 155° F (68°C) Enloy
®
, White (Paint), and Escutcheon, or recessed with
and 175° F (79° C)
Navajo White E-1 Recessed Escutcheon
3
Base part number shown. For complete part number, see price list.
4
This chart shows the listings and approvals available at the time of printing. Other approvals are
in process. Check with the manufacturer for any additional approvals.
5
Listing is for residential occupancies with smooth, flat, horizontal ceilings.
6
Listing is for residential occupancies with smooth ceilings with slopes up to and including a 6/12
(26.6°) pitch.
7
Listed by Underwriter’s Laboratories, Inc. for use in Canada.
8
Acceptance for use by City of New York Department of Buildings is pending.
9
For areas of coverage smaller than shown, use the "Minimum Water Supply Requirement" for the
next largest area listed with sprinklers of similar K factor.
10
Areas under sloped ceilings must be measured along the ceiling slope. Actual floor coverage under
sloped ceilings will be less than the listed Area of Coverage.
11
Metric K Factor shown is for use when pressure is measured in kPa. When pressure is measured in
BAR, multiply the metric K Factor shown by 10.0.
12
The Model F-1 Adjustable Escutcheon is considered a surface-mounted escutcheon because it does
not allow the fusible element of the sprinkler to be recessed behind the face of the wall or ceiling.
NOTE: Install residential pendent sprinklers with deflectors between 1" (3/4" for recessed) & 4" below
the ceiling.
Maximum Areas
Minimum Water Supply Requirements
of Coverage
9
Single Sprinkler
Two or More
UL
5
ULC
7
NYC
8
12’ X 12’
11.5 GPM @ 7.2 PSI
11.5 GPM @ 7.2 PSI
3.7m X 3.7m
43,5 L/Min @ 49,3 kPa
43,5 L/Min @ 49,3 kPa
A1X A1X
--
14’ x 14’
13 GPM @ 9.1 PSI
11.5 GPM @ 7.2 PSI
4.3m x 4.3m
49,2 L/Min @ 63,0 kPa
43,5 L/Min @ 49,3 kPa
A1X A1X
--
16’ x 16’
13 GPM @ 9.1 PSI
11.5 GPM @ 7.2 PSI
A1X A1X
--
4.9m x 4.9m
49,2 L/Min @ 63,0 kPa
43,5 L/Min @ 49,3 kPa
18’ x 18’
16 GPM @ 13.8 PSI
13.5 GPM @ 9.9 PSI
A1X A1X
--
5.5m x 5.5m
60,6 L/Min @ 95,6 kPa
51,1 L/Min @ 68,0 kPa
20’ x 20’
19 GPM @ 19.5 PSI
17 GPM @ 15.6 PSI
A1X A1X
--
6.1m x 6.1m
71,9 L/Min @ 134,6 kPa
64,4 L/Min @ 107,8 kPa
Sloped Ceiling Approvals
10
Maximum Area
Minimum Water Supply Requirements
of Coverage
9,10
Single Sprinkler
Two or More
UL
5
ULC
7
NYC
8
16’ X 16’
18 GPM @ 17.5 PSI
13 GPM @ 9.1 PSI
4.9m X 4.9m
68,1 L/Min @ 120,7 kPa
49,2 L/Min @ 63,0 kPa
A1X A1X
--
Deflector
Thread
Nominal
Overall
Style
Size NPT
K Factor
11
Length
Base Part Number
3
1/2 inch
4.3 US
2.25 inch
Pendent
(15mm)
(6,2 metric)
(57,2mm)
09530
AREAS OF COVERAGE
4
SAMPLE
Temperature
Finish
A1X
Escutcheon
Sprinkler
Nominal Sprinkler
Ceiling Temperature at Sprinkler
Temperature
Temperature
Rating
Max. Ambient Max. Recommended
Bulb
Classification (Fusing Point)
Temp. Allowed
1
Ambient Temp.
2
Color
Ordinary
155°F (68°C)
135°F (46°C)
100°F (38°C)
Red
Intermediate
175°F (79°C)
155°F (68°C)
150°F (65°C)
Yellow
Sprinkler Finishes: Brass, Bright Brass, Chrome-Enloy
®
(patents pending), White(Paint), and Navajo
White(Paint)
1
Based on National Fire Prevention and Control Administration, Contract No. 7-34860.
2
Based on NFPA-13. Other limits may apply depending on fire loading, sprinkler location, and other
Authority-Having-Jurisdiction requirements. Refer to specific installation standards.
MICROFAST
®
MODEL M-4
SMALL ORIFICE RESIDENTIAL
PENDENT SPRINKLER
OBSOLETE
