DSC MXBase, MX916, MX926, MX936 - Application & Design Document

*29011152R001*
MXBASE AND MX916/926/936 PRODUCT
APPLICATION AND DESIGN DOCUMENT
29011152R001 2
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Contents
Contents
Cautions, warnings, and regulatory information.........................................................................................5
Introduction...................................................................................................................................................... 5
Detector overview............................................................................................................................................ 5
Detector operation modes................................................................................................................... 6
Detector specifications
..........................................................................................................................7
Detector functions
.................................................................................................................................7
Self-monitoring
.............................................................................................................................................7
Self-test
..........................................................................................................................................................8
LED Status indicator
.....................................................................................................................................8
Remote LED
...................................................................................................................................................8
Short-circuit line isolator............................................................................................................................. 8
Detector Address..........................................................................................................................................8
Threshold compensation............................................................................................................................ 8
Detector mode selection
................................................................................................................................. 9
Selection guidelines
...............................................................................................................................9
Detector selection and placement guidelines
............................................................................................ 11
General considerations.......................................................................................................................11
Code compliance rules
........................................................................................................................11
Detector spacing rules
........................................................................................................................ 12
Correct detector locations.................................................................................................................. 12
Incorrect detector locations............................................................................................................... 15
Maintenance, testing and cleaning
..............................................................................................................16
Maintenance
.........................................................................................................................................16
Testing...................................................................................................................................................16
Detector testing method
.................................................................................................................... 16
Cleaning
................................................................................................................................................ 17
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
3 4
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Cautions, warnings, and regulatory information
READ AND SAVE THESE INSTRUCTIONS
Follow the instructions in this installation manual. These
instructions must be followed to avoid damage to this product and associated equipment. Product
operation and reliability depend upon proper installation.
DO NOT INSTALL ANY PRODUCT THAT APPEARS DAMAGED
Upon unpacking your Tyco
product, inspect the contents of the carton for shipping damage. If damage is apparent,
immediately file a claim with the carrier and notify an authorized product supplier.
ELECTRICAL HAZARD
Disconnect electrical field power when making any internal
adjustments or repairs. All repairs should be performed by a representative or an
authorized agent of your local Tyco product supplier.
STATIC HAZARD
Static electricity can damage components. Handle as follows:
• Ground yourself before opening or installing components.
• Prior to installation, keep components wrapped in anti-static material at all times.
Introduction
Use this guide when designing a fire detection system using addressable detectors, or replacing

addressable detectors in an existing system. This document includes information about detector

features, choosing detectors, and choosing detector locations. It is an overall guide to the Photo-
Heat, Photo, Heat, and Photo-Heat-CO addressable detectors, and includes only information

that
is common to all of them. Refer to document 29011151: MX916/926/936 FIRE DEVICES

INSTALLATION INSTRUCTIONS for information about ordering and installing the detectors.
Note:
There are a number of system level guides available for download from the DSC
website: www.dsc.com. These support the design, installation and use of fire alarm systems.
Detector overview
The function of the detector is to quantify environmental variables and provide the resulting
numerical value to the fire alarm control panel (FACP). The FACP then processes the detector
values and assesses whether an alarm needs to be issued. Depending on the detector variant, the
environmental variables monitored are combinations of the following:
• Temperature
• Smoke density
5
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Figure 1:
Detector communications
Detector operation modes
Table 1 lists the operation modes that are applicable to each detector type.
Table 1:
Detector operation modes
PID
Detector name
UL-listed smoke
sensitivity
Modes of operation*
MX916
Photo-Heat
2.26 ± 0.42%/ft
1. Optical
2. Heat enhanced optical (HPO)
3. Fixed alarm level temperature 200
°F (93.4 °C)
MX926
Photo
2.26 ± 0.42%/ft
Optical
MX936
Heat
1. Fixed alarm level temperature 135
°F (57 °C)
2. Fixed alarm level temperature 200
°F (93.4 °C)
3. Rate of rise 15 °F (8.4 °C)
* The modes are configured using the ES Panel Programmer. Refer to document 574-849: ES Panel
Programmer's Manual for information about configuring the devices.
Table 2:
Documents list
Detector type
Document
MX916
Photo-Heat
MX926
Photo
MX936
Heat
29011151:
MXBASE & MX916/926/936 FIRE DEVICES INSTALLATION

INSTRUCTIONS ENG
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
6 Detector specifications
Table 3 displays the specifications for each of the detectors.
Table 3:
Detector specifications
MX916 Photo-Heat
MX926 Photo
MX936 Heat
Environment
Indoor application only
Relative humidity
93% non-condensing
Dimensions
Height: 42 mm (1.653 in.)
Diameter: 108 mm (4.252 in.)
Weight
76 g
81 g
Operating temperature
-25°C to +70°C (-13°F to
+158°F)
+1°C to +49°C (+33.8°F
to +120.2°F)
-25°C to +70°C (short
term to +90°C) (-13°F
to +158°F (short term
to 194°F))
Storage temperature
-30°C to +70°C (-22°F to
+158°F)
-30°C to +70°C (-22°F
to +158°F)
-30°C to +70°C (-22°F
to +158°F)
Operating voltage
20 VDC to 40 VDC maximum
Stand-by current
350 uA
Alarm current
4 mA
Detector functions
Table 4 displays the detector functions that are provided with the types of detectors.
Self-monitoring
Self-monitoring refers to the design features of the detector to detect problems. The features for
each detector type follow:
• For the heat (temperature) sensor, a normal output level around ambient temperature is
expected.
• For the optical (smoke) sensors, the optical chamber is periodically stimulated.
Note:
When the Photo detector is dirty, you must replace it.
Table 4:
Detector functions
Detector types
Function
MX916
Photo-Heat
MX926
Photo
MX936
Heat
Self-monitoring
X
X
X
Self-test
X
X
X
LED Status indicator
X
X
X
Remote LED
X
X
X
Threshold compensation
X
X
7
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Note:
Please refer to 29011151: MXBASE & MX916/926/936 FIRE DEVICES INSTALLATION

INSTRUCTIONS ENG for more details on the configuration options for the detector features.
Self-te st
The self-test feature simulates a fi
re condition within the detector. The detector then re acts as if
there is an actual fire.
LED Status indicato r
The LED status indicator is configura ble by t he installer (ON/OFF). The LED has the followi ng
variations:
• A
flashing yellow LED indicates a detector fault or isolation.
• A
flashing re d LED indicates normal operat ion (flashes on detector poll).
• A
continuous re d LED indicates the detector is in alarm.
Remote LED
The detectors are capable of driving a remote LED. Please refer to
29011151: MXBASE &

MX916/926/936 FIRE DEVICES INSTALLATION INSTRUCTIONS ENG for remote LED wiring details.
Short-circuit line isolator
A detector with a built-in short-circuit line isolator continues to operate when a single short circuit

fault occurs in a loop.
Detector Address
Each detector will be assigned an address automatically during the MX devices enrollment process.
Note:
The detectors should be wired into the MX loop before the start of the auto-enroll
process.
Threshold compensation
The detectors support the ability to compensate for the effects of contamination due to dust and
dirt. This prevents an increase of false alarms and extends the operational life of the detector.
Threshold compensation applies only to detectors with smoke (photo) sensors.
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
8 Detector mode selection
Selection guidelines
Choose detectors based on the demands of the application.
The tables below are guidelines. Specific situations are likely to require variations on the suggested
detector types. Real-life situations may require detector combinations to cover all likely risks. The
chief difference is a higher resistance to false alarms and slower response to aerosol test gas.
Consider customer knowledge of relative impact of false alarm versus undetected fires.
The Night and Day columns represent low false alarm risk and high false alarm risk. Although this
usually follows a day/night pattern, it may be configured for any time. For example, the car deck of
a ferry would be configured for day during vehicle loading and night after all the passengers had
left the car deck, thus achieving optimum protection for that area.
Detector key
Mode key
PH
= MX916
HPO
= Heat enhanced optical
P
= MX926
P
= Optical (Photoelectric)
H
= MX936
135F
= 135F Fixed temperature
200F
= 200F Fixed temperature
Ror
= 15F Rate of rise of temperature
X
= Use manual call point
9
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Note:
Bold text indicates most likely detector and mode to meet user's requirements.
Sensitivity settings may require adjustment depending on the environment.
Table 5:
Variations on suggested detector types
Variations
Environment
Very clean and dry
Benign, moderately
clean, regulated
temperature
Dirty or smoking
during the day
Dusty or humid
Hot and smoky when
in use
Open areas
For example
Clean room, data
processing suite
Offices, hospitals,
light industrial,
residential, passenger
cabin
Warehouse with
diesel fork-lifts or
similar vehicles, heavy
industrial, ferry car
deck
Livestock pen, mill,
laundry, changing
room
Kitchen, engine room,
test beds
Atrium, theatre,
hanger, oil rigs, turbine
hall
Type
Mode
Type
Mode
Type
Mode
Type
Mode
Type
Mode
Type
Mode
Fire loading
Night
Day
Night
Day
Night
Day
Night
Day
Night
Day
Night
Day
Electronic equipment,
electrical switchgear,
electric motors, cable
conduit
PH
P
HPO
H
PH
P
HPO
H
PH
HPO
H
PH
HPO
H
PH
H
HPO
Ror
X
200F
Flame
Fabrics, clothes, soft
furnishings, paper,
cardboard, plastic
foams, animal bedding,
wood shavings
PH
P
HPO
H
PH
HPO
H
PH
HPO
H
PH
HPO
H
Flammable liquids,
paints, solvents,
flammable gasses,
unstable chemicals
PH
P
HPO
HPO
PH
HPO
HPO
H
Ror
135F
H
Ror
135F
H
Flame
Ror
200F
X
Flame
X
Food stuffs, general
organic waste, animal
fodder, wooden
structures, solid fuels
PH
P
H
HPO
Ror
H
Ror
PH
HPO
HPO
PH
H
HPO
Ror
H
Ror
PH
H
HPO
Ror
H
Ror
H
Ror
200F
Plastic, chemicals,
machinery, building
materials, unknown
contents
PH
HPO
H
PH
P
H
HPO
Ror
H
Ror
PH
P
H
HPO
Ror
H
Ror
P
P
P
H
Ror
200F
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
10 Detector selection and placement guidelines
Important:
The sections that follow provide information in accordance with NFPA 72. Use the
standards applicable to your location if you are not in NFPA jurisdiction.
General considerations
Before installing the detectors, survey the area to be covered in accordance with information
provided in NFPA 72 (an excerpt is provided in the note of Table 6). For additional information, refer
to NFPA 72 and the NEMA Guide for Proper Use of System Smoke Detectors.
See Table 6 for various considerations when choosing detector locations and types:
Table 6:
Detector selection considerations
Considerations
Possibility of human occupancy
Contents to be protected
Type of construction and use
Contents fire characteristics
Air movement - stratification
Deflections and obstructions
Ceiling heights
Ceiling surface conditions
Ceiling construction types
Total area
Vent locations - velocities -
dilution
Note:
Each detector is capable of providing up to 900 sq. ft. (84 m²) of coverage, depending
on the local code requirements and engineering evaluation results.
Code compliance rules
Underwriters Laboratories (UL) has three smoke detector standards. Use the detectors only in
applications for which they are specifically listed. The three standards are as follows:
1.
UL 268A standard for duct detectors
2.
UL 217 standard for single and multiple station detectors
3.
UL 268 standard for system-type detectors
The NFPA 101 Life Safety Code states that single station detectors shall sound an alarm only within
an individual living unit or similar area and shall not actuate the building fire alarm system. It
also states, “All systems and components shall be approved for the purpose for which they are
installed”.
In addition to possible code noncompliance, the following deficiencies would exist in a series of
residential detectors connected in a fire alarm system mode:
•
Because the fire alarm system is not supervised, vandals or others could disconnect a detector
or the entire system, leaving a building without protection. The residents would be unaware of
the serious life threatening condition.
•
Residential detectors do not latch in alarm. In other words, the detector self-resets. One
detector in alarm sounds all the detectors connected together. It would be difficult to identify
or locate a specific detector that initially put the system into alarm after the alarm condition
was cleared.
System detectors latch in alarm. They do not reset until power is momentarily disconnected. This
makes it convenient to identify the location of the detector that caused the control panel to alarm.
In addition, system detectors are specifically designed to connect to a supervised control panel.
Twowire detectors require a UL compatibility review to verify that the detector and panel properly
operate together. A typical life safety fire alarm system for an apartment complex would be to use
system detectors and manual fire alarm stations in the hallways and common areas of the complex
and residential single station type detectors and heat detectors in the individual apartments. The
11
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT system detectors, manual stations and heat detectors would be connected to a supervised control
panel, sound a general alarm and automatically notify the proper authorities that a fire condition
exists. The residential detectors located in the apartments would be interconnected only within the
individual living quarters of each apartment. These residential units would sound an alarm only in
the apartment unit.
Detector spacing rules
Table 7 lists the detector spacings required:
Table 7:
Detector spacing requirements
Agency
Program selection
Spacing
UL
135ºF / 200ºF (57ºC / 93ºC)
50 ft. x 50 ft. (15.24 m x 15.24
m) ceiling
30 ft. x 30 ft. (9.15 m x 9.15 m)
wall
Correct detector locations
Important:
The guidelines in this section are adapted from standards published by the
National Fire Protection Association, Quincy, Massachusetts, U.S.A. These standards include
NFPA 72, “National Fire Alarm and Signaling Code”; NFPA 70, “National Electrical Code”, Article
760; and NFPA 90A, “Standard for the Installation of Air Conditioning and Ventilating Systems".
To provide effective early warning of a developing fire situation, detectors should be installed
in all areas of the protected premises. Total coverage as defined by NFPA 72 should include
all rooms, halls, storage areas, basements, attics, lofts, and spaces above suspended ceilings
(including plenum areas utilized as part of the HVAC system). In addition, this should include all
closets, elevator shafts, enclosed stairways, dumbwaiter shafts, chutes and other subdivisions and
accessible spaces.
Fire detection systems installed to meet local codes or ordinances may not be adequate for
early warning of the fire. Some codes or ordinances have minimum objectives such as capturing
elevators or preventing circulation of smoke through HVAC systems, instead of early detection of
fire.
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
12 You should weigh the costs against the benefits of installing a complete fire detection system when
any detection system is being installed. The location, quantity and zoning of detectors should be
determined by what objectives are needed rather than the minimum requirements of any local
codes or ordinances. Detectors may be omitted from combustible blind spaces when any of the
conditions in Table 8 prevail.
Table 8:
Conditions for when detectors can be omitted from combustible blind spaces
Ommission from compustible blind spaces
The ceiling is attached directly to the underside of the supporting beams of a combustible roof or
floor deck.
The concealed space is entirely filled with noncombustible insulation. In solid joist construction,
the insulation need fill only the space from the ceiling to the bottom edge of the joist of the roof or
floor deck.
There are small concealed spaces over rooms, provided the space in question does not exceed 50
sq. ft. (4.6 m²).
The spaces formed by sets of facing studs or solid joists in walls, floors, or ceilings where the
distance between the facing studs or solid joists does not
exceed 6 in. (15 cm).
The space is not accessible for storage purposes. It is protected against the entrance of
unauthorized persons and against the accumulation of windblown debris.
The space contains no equipment or structures (such as steam pipes, electrical wiring, ducts,
shafts, or conveyors) that could potentially ignite or conduct the spread of fire.
The floor over the space is tight.
Non flammable liquids are processed, handled, or stored on the floor above the space.
Detectors are usually required or recommended underneath open loading docks or platforms and
their covers, and in accessible under-floor areas in buildings without basements. Detectors can also
be omitted from below open grid ceilings where all of the conditions in Table 9 are met.
Table 9: Conditions for detector omissions
Conditions for detector ommissions
The openings of the grid are at least 1/4 in. (6 mm) in the smallest dimension.
The thickness of the material does not exceed the smallest of the grid openings.
The openings constitute at least 70% of the area of the ceiling material.
“Total coverage” as described in NFPA 72 is the definition of a complete fire detection system.
In some of the specified areas of coverage, such as attics, closets, under open loading docks
or platforms, a heat detector may be more appropriate than a smoke detector. Give careful
consideration to the detector manufacturer’s instructions, and the recommendations in this guide.
Generally, when only one detector is required in a room or space, place it as close to the center of
the ceiling as possible. Central location of the detector is best for sensing smoke and/or fire in any
part of the room. If a center location is not possible, it may be placed no closer than 4 in. (10 cm)
from the wall, or if listed for wall mounting, it may be mounted on the wall. Wall mounted detectors
must have a distance between 4 in. and 12 in. (10 cm to 30 cm) from the ceiling to the top of the
detector, and at least 4 in. (10 cm) from any corner wall junction, see Figure 2.
13
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Figure 2:
Wall and ceiling-mounted detector
When an air supply and/or an air return duct opening is present in a room or space, place the
detectors in the path of the air flow toward the return air duct opening, see Figure 3.
Figure 3:
Detector placement - air supply and/or return ducts
Use smoke tests to determine correct detector placement. Give special attention to smoke velocity
and travel direction because either can affect detector performance.
Placing a detector near air conditioning or incoming air vents can lead to excessive accumulation of
dust and dirt on the detector causing it to malfunction and trigger nuisance alarms. Do not locate
detectors closer than 3 ft. (0.9 m) from an air supply diffuser.
Spot-type detectors in properly engineered systems may also be placed in return air ducts, or in
approved duct detector housings designed for this application. Although duct detectors are not a
substitute for open area detectors, they provide an effective method of initiating building control
functions to prevent smoke from being transported from the fire area to other parts of a building.
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
14 Incorrect detector locations
One of the major causes of nuisance alarms is incorrect detector placement. The best way to avoid
nuisance alarms is to avoid installing detectors in environments that cause them to malfunction.
See Table 10 for examples of unsuitable detector locations, Table 11 for environmental conditions
that affect the detectors.
Table 10:
Examples of improper detector locations
Examples of improper detector locations
Excessively dusty or dirty areas, such as feed rooms and steel mills. Dust and dirt can accumulate on the detector’s sensing
chamber and make it overly sensitive. It can also block the air entrances to the sensing chamber and make the detector less
sensitive to smoke.
Important:
Avoid areas where fumigants, fog or mist-producing materials, or sweeping and cleaning compounds are
used. These substances may cause nuisance alarms.
Outdoors, in stables, open storage sheds, or other open structures affected by dust, air currents, or excessive humidity and
temperature.
Damp or excessively humid areas, such as next to bathrooms with showers. The moisture entering the sensing chamber can
cool and condense into water droplets, making the detector overly sensitive and causing a nuisance alarm.
In elevator lobbies over ashtrays or where people smoke while waiting for the elevator.
Very cold or hot environments, such as in unheated buildings and rooms where the temperature can fall below or exceed
the operating temperature range of the detector. At temperatures below 32 °F (0 °C), ice crystals or condensation can
appear inside the sensing chamber, make it overly sensitive, and cause a nuisance alarm. The internal components of the
detectors may not function properly at temperatures above the maximum value of the operating range.
In or near areas where combustion particles are normally present. Examples include:
•
Kitchens or other areas with ovens and burners.
•
Garages, where particles of combustion are present in vehicle exhausts.
•
Within 5 ft. (1.5 m) of any cooking appliance.
•
Within 15 ft. (4.5 m) of any type of furnace, hot water heater, or gas space heater.
•
Welding shops or other types of work areas where some form of combustion is used in the activity normally
conducted in that area.
Note:
When a detector must be located in or adjacent to such an area, a fixed temperature heat detector may be
appropriate.
In air streams passing by or through kitchens. Air often enters a residence or a residential unit of an apartment building
through cracks around the front and/or back doors. If the air return is in the bedroom hallway or in the bathroom, and if air
from the kitchen easily enters the air stream going from the door to the air return, combustion particles from cooking can
cause nuisance alarms.
Note:
Install detectors so that they protect the bedrooms, but so they are out of the air stream.
In or near manufacturing areas, battery rooms, or other areas where substantial quantities of vapors, gases or fumes may
be present. Strong vapors, like excessive humidity, can make detectors overly sensitive or less sensitive than normal. In
very large concentrations, gases heavier than air, such as carbon dioxide, can make detectors more sensitive, while gases
lighter than air, such as helium, may make them less sensitive. Aerosol particles can collect on chamber surfaces and cause
nuisance alarms.
Insect-infested areas. If insects enter a detector’s sensing chamber, they can cause a nuisance alarm. Take appropriate
pest control actions prior to installing detectors in such locations. If spraying is done, do not allow insect spray to enter the
detectors.
Near fluorescent light fixtures. Electrical noise generated by fluorescent light fixtures can cause nuisance alarms.
Note:
Install detectors at least 1 ft. (0.3 m) away from such light fixtures.
15
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT Table 11:
Environmental conditions influencing detector response*
Detector
protection
Air velocity
>300 ft. (91.4
m)/min
Atm. pressure
300 ft. (914 m)
above sea level
Humidity
>93% RH
Temp. <32 °F
(0 °C) >100 °F
(38 °C)
Smoke color
Ion
X
X
X
X
O
Photo
O
O
O
X
X
Beam
O
O
X
X
O
Air sampling
O
O
X
X
O
*Refer to Table A-5-3.6.1.1 in NFPA 72.
X = May affect detector response
O = Generally does not affect detector response
Maintenance, testing and cleaning
Maintenance
The minimal requirement for detector and sensor maintenance consists of clearing surface dust
b y using a vacuum cleaner. Ensure cleaning programs comply with NFPA and local environments.
Cleaning of the internal chamber must be done only by a qualified technical representative. For
service, contact your local branch office.
Testing
Smoke sensor sensitivities are set and continuously monitored by the FACP. Dirty or out-of-range
sensors are annunciated by the FACP. This functionality complies with NFPA 72.
Note:
When testing detectors or sensors, refer to NFPA 72, or contact your local branch office.
CAUTION:
Before functionally testing the detectors, be sure to disconnect the city connection,
releasing devices, extinguishing systems, and place the detectors in Walktest mode using the
HSM3105MX panels.
Detector testing method
NFPA minimally requires annual functional testing of smoke detectors/sensors at their installed
location. To perform this annual test, see Table 12 for a list of available equipment.
Table 12:
Test equipment
Product
Function
Solo 336 Aerosol Smoke Dispenser
Attached to either the Solo 100 (15 ft. (4.572 m))
telescopic fiberglass pole or the Solo 101 (4 ft.
(1.219 m)) fiberglass pole.
Testifire 2000-024
Smoke, Heat and CO Detector Tester.
Testifire 2001-024
Smoke, Heat and CO Detector Test Kit (includes
two battery batons and AC/DC charger).
TS3-024 Smoke Capsule
For use with Testifire Smoke, Heat and CO
Detector Tester.
Note:
Refer to the user’s manual provided with each device for user instructions.
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT
16 Cleaning
No user serviceable parts inside. If the device’s sensitivity is other than what is marked on the
device’s label, replace the device.
CAUTION:
Notify appropriate building personnel before removing any detectors.
Important:
After replacement, test the detector or sensor with smoke in accordance with
NFPA 72.
17
MXBASE AND MX916/926/936 PRODUCT APPLICATION AND DESIGN DOCUMENT © 2022 Johnson Controls. All rights reserved. All specifications and other information shown were current as of document
revision and are subject to change without notice. Additional listings may be applicable, contact your local Tyco product
supplier for the latest status. Listings and approvals under Tyco and the product names listed in this material are marks
and/or registered marks. Unauthorized use is strictly prohibited. NFPA 72 and National Fire Alarm Code are registered
trademarks of the National Fire Protection Association (NFPA).