UL 268
Smoke Detectors for Fire Alarm Systems

DETAILS
Edition Number:6SCC Approved:--
Edition Date:2009-08-14DOD Approved: --
Price Code:CANSI Approved: 2009-08-14
Type:ululc

  • SCOPE

    1 Scope

    1.1 This Standard sets forth requirements for smoke detectors and mechanical guards to be employed in ordinary indoor locations in accordance with the following:

    In the United States:

    a)     National Fire Alarm Code, NFPA 72.

    In Canada:

    b)     Standard for the Installation of Fire Alarm Systems, CAN/ULC-S524;

    c)     National Building Code of Canada; and

    d)     National Fire Code of Canada.

    1.2 A smoke detector (e.g. ionization-type, photoelectric-type and the like) as covered by this Standard consists of an assembly of electrical components arranged to detect one or more products of combustion. The products of combustion may consist of gases, water vapor, and visible as well as invisible smoke particles. The detector includes provision for the connection to a source of power, signaling, and optional remote control circuits. Additional functionality, such as a heat detector, or audible signaling appliance/device, or both, is permitted to be incorporated as part of the smoke detector assembly.

    1.3 This standard covers the following types of detectors:

    a)    Detectors intended for open area protection and for connection to a compatible power supply or control unit for operation as part of a fire alarm system.

    b)    Detectors intended solely for control of releasing devices such as electromagnetic door holders, fire dampers or smoke dampers.

    c)    Detectors intended for both applications described in (a) and (b) above, and

    d)    In Canada, duct detectors.

    1.4 This standard does not cover the following:

    In the United States (a – f):

    a)    Control units to which the detectors are intended to be connected that are covered by the Standard for Control Units for Fire-Protective Signaling Systems, UL 864;

    b)     Self-contained single and multiple station smoke alarms, not intended for connection to a system control unit, that are covered by the Standard for Single and Multiple Station Smoke Alarms, UL 217;

    c)    A heat detector incorporated as a part of a smoke detector assembly, and covered by the Standard for Heat Detectors for Fire Protective Signaling Systems, UL 521; except for the requirements of the Fire Test (Heat Detector);

    d)    Fire tests for smoke detectors integral with combination door closers and holders that are covered by the Standard for Door Closers-Holders, With or Without Integral Smoke Detectors, UL 228;

    e)    Commercial-residential detectors not intended for connection to a system control unit that are covered by the Standard for Smoke Detector Monitors and Accessories for Individual Living Units of Multifamily Residences and Hotel/Motel Rooms, UL 1730;

    f)    Detectors for monitoring the smoke density within flues or stacks;

    In Canada (g – k):

    g)    Control units that are covered by the Standard for Control Units for Fire Alarm Systems, ULC-S527;

    h)    Self-contained single and multiple station smoke alarms that are covered by the Standard For Smoke-Alarms, CAN/ULC-S531;

    i)    A heat detector incorporated as a part of a smoke detector assembly, and covered by the Standard For Heat Actuated Fire Detectors for Fire Alarm Systems, CAN/ULC-S530;

    j)    Fire tests for smoke detectors integral with combination door closers and holders that are covered by the ULC/ORD-C228,  Door Closers and Holders;

    k)    Detectors for monitoring the smoke density within flues or stacks; and

    l)    Wireless Smoke Detectors.

    1.5 These requirements also cover all remote accessories that are intended to be connected to a smoke detector.

  • TABLE OF CONTENTS
    Expand All

    • Cover
    • Transmittal
    • UL Harmonized Standard Title Page
    • Table of Contents
      • SMOKE DETECTORS FOR FIRE ALARM SYSTEMS
        • INTRODUCTION
          • 1 Scope
          • 2 General
            • 2.1 Assembly
            • 2.2 Components
            • 2.3 Units of measurement
            • 2.4 Reference publications
          • 3 Glossary
          • 4 Detector reliability prediction
          • 5 Installation and operating instructions
        • CONSTRUCTION
          • Assembly
          • 6 General
            • 6.1 Remote accessories
            • 6.2 Sensitivity indicating means
            • 6.3 Radioactive materials
            • 6.4 Insect guards
            • 6.5 Supplementary heat detector
            • 6.6 Alarm verification feature
            • 6.7 Maintenance (cleanability)
          • 7 Compatibility information
            • 7.1 General
            • 7.2 Method of evaluation
            • 7.3 Changes affecting compatibility
          • 8 Servicing and Maintenance Protection
            • 8.1 General
          • 9 Enclosure
            • 9.1 General
            • 9.2 Cast metal enclosures
            • 9.3 Sheet metal enclosures
            • 9.4 Nonmetallic enclosures
            • 9.5 Ventilating openings
            • 9.6 Covers
            • 9.7 Glass panels
          • 10 Corrosion protection
          • 11 Field Wiring Connections
            • 11.1 General
            • 11.2 Field wiring compartment
            • 11.3 Field wiring terminals and leads
            • 11.4 Field wiring leads
            • 11.5 Grounding terminals and leads
            • 11.6 Grounded supply terminals and leads
            • 11.7 Isolated (nongrounded) detectors
          • 12 Internal Wiring
            • 12.1 General
            • 12.2 Wireways
            • 12.3 Splices
            • 12.4 Barriers
            • 12.5 Strain relief
          • 13 Bonding for Grounding
          • COMPONENTS
          • 14 General
            • 14.1 Mounting of components
            • 14.2 Operating components
            • 14.3 Current-carrying parts
          • 15 Bushings
          • 16 Electrical Insulating Material
          • 17 Lampholders and Lamps
          • 18 Photocell Illuminating Lamps and Light Emitting Diodes (LEDs)
            • 18.1 General
            • 18.2 Quality assurance program
          • 19 Motors
          • 20 Protective Devices
          • 21 Printed Wiring Boards
          • 22 Switches
          • 23 Transformers and Coils
          • 24 Dropping Resistors
          • 25 Batteries (United States Only)
            • 25.1 General
            • 25.2 Battery connections
          • 26 Spacings
        • PERFORMANCE
          • 27 General
            • 27.1 Test units
            • 27.2 Test voltages
            • 27.3 Test samples and data
            • 27.4 Component reliability data
            • 27.5 Remote accessories
            • 27.6 Detector guards (United States only)
          • 28 Normal Operation Test
            • 28.1 General
            • 28.2 Standardized alarm signal (United States only)
            • 28.3 Sensitivity shift criteria
          • 29 Electrical Supervision Test
            • 29.1 General
            • 29.2 Component Failure
            • 29.3 Photocell illuminating lamps and light emitting diodes (LEDs)
            • 29.4 Battery powered units (United States only)
            • 29.5 Chamber monitoring
          • 30 Sensitivity Test
            • 30.1 General
            • 30.2 Combustibles
            • 30.3 Aerosol generation equipment (alternate method)
            • 30.4 Test equipment
            • 30.5 Test method
            • 30.6 Uniformity of operation
            • 30.7 Sensitivity test feature
          • 31 Directionality Test
          • 32 Velocity-sensitivity Test
          • 33 Smoke Entry (Stack Effect) Test
          • 34 Lamp Interchangeability Test (Photoelectric)
          • 35 Reduction in Light Output Test
          • 36 Stability Test
          • 37 Test for Effect of Air Velocity
          • 38 Fire Tests
            • 38.1 General
            • 38.2 Paper fire
            • 38.3 Wood fire (United States only)
            • 38.4 Flammable liquid fire
            • 38.5 Igniter assembly
            • 38.6 Test method
          • 39 Smoldering Smoke Test
          • 40 Smoldering Smoke Test – Maximum Obscuration Without Alarm
          • 41 Circuit Measure Test
            • 41.1 General
            • 41.2 Battery trouble voltage determination (United States only)
          • 42 Overvoltage and Undervoltage Tests
            • 42.1 Overvoltage test
            • 42.2 Undervoltage test
            • 42.3 Two-wire smoke detectors
          • 43 Temperature Test
          • 44 Vibration Test
          • 45 Replacement Test, Head and Covers
          • 46 Jarring Test
          • 47 Variable Ambient Temperature Tests
            • 47.1 Operation in high and low ambients
            • 47.2 Effect of shipping and storage
          • 48 Humidity Test
          • 49 Corrosion Tests
          • 50 Transient Tests
            • 50.1 General
            • 50.2 Internally induced transients
            • 50.3 Extraneous transients
            • 50.4 Supply line (hazardous-voltage) transients
            • 50.5 Supply line (extra-low-voltage circuit) transients
          • 51 Static Discharge Test
          • 52 Dust Test
          • 53 Overload Tests
            • 53.1 Detector
            • 53.2 Separately energized circuits
          • 54 Endurance Test
          • 55 Fire Test – Heat Detector
          • 56 Abnormal Operation Test
          • 57 Locked Rotor Test
            • 57.1 Motors
            • 57.2 Thermal or overcurrent protection (United States only)
            • 57.3 Impedance protection (United States only)
          • 58 Dielectric Voltage-Withstand Test
          • 59 Polarity Reversal Test
          • 60 Tests on Polymeric Materials
            • 60.1 General
            • 60.2 Temperature test
            • 60.3 Flame test – 19 mm (3/4-inch)
            • 60.4 Flame test – 127 mm (5-inch)
          • 61 Strain Relief Test
          • 62 Non-compulsory Fire and Smoldering Smoke Tests (United States Only)
          • 63 Survivability Test
          • 64 Audibility Test
            • 64.1 General
            • 64.2 Sound output measurement (United States only)
            • 64.3 Sound output measurement (Canada only)
          • 65 Field Service Tests
            • 65.1 Go/no-go field test (United States only)
            • 65.2 Maintenance (cleanability)
          • 66 Battery Tests (United States only)
          • 67 Conformal Coatings on Printed Wiring Boards
            • 67.1 Low voltage printed wiring boards
            • 67.2 High voltage printed wiring boards
          • 68 In Canada only – air duct detectors
        • MANUFACTURING AND PRODUCTION
          • 69 General
          • 70 Sensitivity Calibration Tests
          • 71 Smoke Tests
          • 72 Photocell Illuminating Lamp Test
          • 73 Production-Line Dielectric Voltage-Withstand Test
        • MARKING
          • 74 General
          • 75 Packaging Marking (United States Only)
        • INSTRUCTIONS
          • 76 Installation Instructions – Wiring Diagram
            • 76.1 All detectors
            • 76.2 Four-wire detectors
            • 76.3 Two-wire detectors
          • 77 Technical Bulletin
        • FIGURES
    • ANNEX A – TYPICAL CANADIAN SENSITIVITY SMOKE TEST CHAMBER CONSTRUCTION
    • ANNEX B – TYPICAL UNITED STATES SENSITIVITY SMOKE TEST CHAMBER CONSTRUCTION
    • ANNEX C – OBSCURATION CALCULATIONS
    • ANNEX D – RELIABILITY PREDICTION AND CRITERIA FOR ACCEPTANCE
    • ANNEX E – STANDARDS FOR COMPONENTS
    • ANNEX F – TYPICAL AIR DUCT DETECTOR TEST FACILITY (CANADA ONLY)
    • ANNEX G – FRENCH TRANSLATIONS OF REQUIRED MARKINGS