Thursday, February 29, 2024

Smoke Control for Dummies

The Basics of Smoke Control Made Simple

Do you struggle to understand smoke control for fire alarm systems? No need to stress out as you are not alone. Let's break it down so it is easier to digest.

Smoke control is a vital aspect of fire protection engineering that aims to prevent the spread of smoke and toxic gases in buildings during a fire. Smoke control systems use various strategies, such as mechanical ventilation, pressurization, and compartmentation, to limit the movement of smoke and protect the occupants and property from its harmful effects. In this blog post, you will learn about the principles, design, and applications of smoke control systems, as well as the relevant codes and standards that govern their performance. You will also find some useful resources and references to help you further explore this topic. Whether you are a fire protection engineer, a building owner, an installer, or a curious reader, this blog post will provide you with valuable insights into the science and practice of smoke control.

Fire alarm systems are essential for the activation and operation of smoke control systems. Fire alarm systems can detect the presence of fire and smoke, alert the occupants and the fire department, and initiate the appropriate smoke control actions. Fire alarm systems can also monitor the status and performance of smoke control systems and provide feedback and control signals to the building management system. Fire alarm systems should be listed, compatible and integrated with the smoke control systems to ensure coordinated and effective response to fire emergencies.

Smoke control systems are complex and require careful design, installation, and maintenance. Smoke control systems should be based on a thorough analysis of the fire hazards, the building characteristics, the occupant needs, and the fire department operations. This approach is referred to as a smoke control report or rational analysis and is required to be completed by a registered fire protection engineer (FPE) per the International Building Code 2021 Section 909.4. The rational analysis or smoke control report will cover which type of smoke control system will be employed (passive vs. mechanical), which smoke control method will be utilized (pressure, exhaust, or air flow), construction methods, sequence of operation and inspection and testing procedures. There are other items covered within the report such as but not limited to stack effect, temperature effect of fire, wind effect, climate and duration of operation. 

What Codes and Standards Dictate Smoke Control Systems?

Smoke control systems are required and regulated by codes and standards that specify the performance requirements, design criteria, installation methods, and testing procedures for different types of buildings and occupancies. Some of the codes and standards that address smoke control systems are as follows:

- 2021 International Building Code (IBC) Chapter 9: Fire Protection and Life Safety    Systems
- ASHRAE Handbook of Smoke Control Engineering
- NFPA 92: Standard for Smoke Control Systems
- NFPA 101: Life Safety Code
- NFPA 72: National Fire Alarm and Signaling Code
- Underwriters Laboratories, UUKL, Smoke Control Equipment (ANSI/864 units for     fire protective signaling systems)

Where are Smoke Control Systems Required per Code?

  • Atriums (three stories or more) within covered malls - IBC 2021 Section 402.7.2.
  • High-Rise Buildings - IBC 2021 Section 403.4.7.
  • Atriums (three stories or more) - IBC 2021 Section 404.5.
  • Underground Buildings - IBC 2021 Section 405.5.
  • Mechanical Access Enclosed Parking Garage -IBC 2021 Section 406.6.4.2.
  • Windowless Buildings Group I-3 - IBC 2021 Section 408.9
  • Large Stages (Greater than 1,000sq' in Area or 50' in Height) - IBC 2021 Section 410.2.7.
Smoke Control Underground Structures
Smoke Control Underground Structures

Smoke control systems can be classified into two main types: passive and mechanical.

Passive smoke control systems rely on the buoyancy and pressure differences of smoke and air to create ventilation openings that allow smoke to escape and fresh air to enter. Examples of natural smoke control systems are automatic opening vents (AOVs), atrium exhausts, opposed airflow, and smoke reservoirs.

  • Openings are protected by automatic closing equipment or devices.
    • Fire Dampers and Combination Fire Smoke Dampers
    • Fire Rated Doors with Magnetic Hold Open Devices (Door Holders)
  • Activation - Consult the Approved Rational Analysis / Smoke Control Report.
    • Smoke Detectors / Heat Detectors located at fire rated doors and combination fire smoke dampers.
    • Duct Smoke Detectors located at HVAC units for shutdown and combination fire smoke dampers. 
  • Verification NOT required.
    • Positive status of fan shutdown, door closure or damper activation is not required per IBC 2021 Section 909.12.1. Consult the rational analysis as it may supersede this code section. 
  • Wiring
    • In addition to the requirements of NFPA 70, all wiring regardless of voltage shall be fully enclosed within a continuous raceway.

Mechanical smoke control systems use fans, dampers, ducts, and other devices to create pressure differences and airflow patterns that control the direction and speed of smoke movement. Examples of mechanical smoke control systems are pressurization method, exhaust method, and air flow method systems.

  • Pressurization Method - IBC 2021 Section 909.6. This approach utilizes pressure differences across smoke barriers to maintain a tenable environment zones adjacent to the smoke control zone of origin. 
    • Per IBC 2021 section 909.6.1, the minimum pressure across the smoke barriers is 0.05" water gauge
    • The maximum pressure differential is dependent upon the opening force of exit doors. Per IBC 2021 section 1010.1.3 #2, the door shall not require more than 30 pounds of force to set in motion and 15 pounds to fully open. 
    • Required to have complete automatic control 2021 IBC section 909.12.3.1.
    • In addition to the requirements of NFPA 70, all wiring regardless of voltage shall be fully enclosed within a continuous raceway.
Smoke Control Pressurization Method Detail
Smoke Control Pressurization Method Detail
Smoke Control Stairwell Pressurization
Smoke Control Stairwell Pressurization

  • Exhaust Method - IBC 2021 Section 909.8. Where approved by the AHJ, the exhaust method may be utilized in large areas such as atriums or malls. Large smoke exhaust fans are utilized to evacuate smoke from the area. Makeup air (MAU) fans, automatic windows or doors may be used to replace air removed from the space by process of the smoke exhaust fan. When the smoke control exhaust method is utilized, the system must keep the smoke layer at least six feet above the highest level meant for egress within the smoke zone. Smoke Control Systems utilizing the exhaust method shall be designed in accordance with NFPA 92.
    • Required to have complete automatic control 2021 IBC section 909.12.3.1.
    • In addition to the requirements of NFPA 70, all wiring regardless of voltage shall be fully enclosed within a continuous raceway.
Smoke Control Exhaust Method Detail
Smoke Control Exhaust Method Detail

Smoke Control Exhaust Method Atrium
Smoke Control Exhaust Method Atrium

  • Air Flow Method - IBC 2021 Section 909.7. Where approved by the AHJ, the air low method is used for facilities with smoke migration through openings that are in the permanently open position. Airflow shall be directed to limit smoke migration from the zone. Airflow shall not exceed 200 feet per minute. Smoke Control Systems utilizing the air flow method shall be designed in accordance with NFPA 92.
  • This method shall not be employed where either the quantity of air or the velocity of the airflow will adversely affect other portions of the smoke control system, intensify the fire, disrupt smoke plume dynamics or interfere with exiting. Airflow towards the fire shall not exceed 200 feet per minute. Where the calculated airflow exceeds this limit, the airflow method shall NOT be used. 909.7.1.
    • Required to have complete automatic control 2021 IBC section 909.12.3.1.
    • In addition to the requirements of NFPA 70, all wiring regardless of voltage shall be fully enclosed within a continuous raceway.
Smoke Control Airflow Method Detail
Smoke Control Airflow Method Detail

Duration of Operation

2021 IBC Section 909.4.6 states that all portions of active or engineered smoke control systems shall be capable of continued operation after detection of the fire event for a period of not less than either 20 minutes or 1.5 times the calculated egress time, whichever is greater. 

What is Verification or Positive Status?

Smoke control equipment utilized in a mechanical smoke control system will be required to comply with IBC 2021 Section 909.12.1 "Verification". This is also known as positive status. This is the process of utilizing fire alarm monitoring modules to supervise the activation of fans, dampers and doors in a smoke control event. The fire alarm monitor modules can be connected to variable frequency drives (VFDs), end switches, pressure differential switches, and current switches. These components provide contact closure to trip the associated fire alarm monitoring module to prove the fan, damper, or doors activated as intended per the approved rational analysis or smoke control port.  
Smoke Control Positive Status Equipment
Smoke Control Positive Status Equipment

Examples of how positive status for smoke control system can be wired to a fire alarm monitoring module. In these examples, a Notifier FDM-1 addressable dual monitor module is used to show how to wire up a damper actuator end switch for normally open and normally closed conditions. 
Fire Smoke Damper Status Monitoring Open Detail
Fire Smoke Damper Status Monitoring Open Detail
Fire Smoke Damper Status Monitoring Closed Detail
Fire Smoke Damper Status Monitoring Open Detail

There is more to smoke control verification.

Another requirement for verification is a preprogrammed weekly self test sequence that shall report abnormal conditions audibly, visually, and by printed report. The pre-programmed weekly test shall operate ALL devices equipment and components used for the smoke control system.

  • Where verification of individual components tested through the preprogrammed weekly testing sequence will interfere with, and produce unwanted effects to, normal building operation, such individual components are permitted to be bypassed from the preprogrammed weekly testing, when approved by the AHJ and in accordance with BOTH of the following:
    1. Where the operation of components is bypassed from the preprogrammed weekly test, presence of power downstream of all disconnects shall be verified weakly by a listed control unit.
    2. Testing of all components bypassed from the preprogrammed weekly test shall be in accordance with section 909.20.6 of the International Fire Code IFC.

Smoke Control System Printer
Example of a UL Listed Smoke Control Printer for Weekly Testing Reports

Fire Fighter's Smoke Control Panel

A fire fighter's smoke control panel for first responder purposes ONLY shall be provided and include manual control or override of automatic control for mechanical smoke control systems. If the facility is a high-rise structure or equipped with smoke protected assembly seating, the fire fighter's smoke control panel shall be installed with the fire command center (FCC). For all other buildings that may require a smoke control system, the fire fighter's smoke control panel shall be installed in an area approved by the AHJ adjacent to the fire alarm control panel. 2021 IBC Section 909.16.

Smoke Control Indication LEDs

All fans, dampers and other operating equipment shall be depicted on the fire fighter's smoke control panel along with clear indication of the airflow. Status indicators shall be included for all smoke control equipment annunciated by fan, damper and or zone. 2021 IBC Section 909.16.1.
  1. Fans, Dampers and Other Operating Equipment NORMAL status = WHITE
  2. Fans, Dampers and Other Operating Equipment OFF or CLOSED status = RED
  3. Fans, Dampers and Other Operating Equipment ON or OPEN status = GREEN
  4. Fans, Dampers and Other Operating Equipment FAULT status = AMBER/YELLOW

Smoke Control Switches

The following switches shall be provided on the smoke control panel to provide control capability over the complete smoke control equipment with the building: 2021 IBC Section 909.16.2
  • ON-AUTO-OFF control over each individual piece of operating smoke control equipment that can be controlled from other sources within the building. This can include: stair pressure fans, smoke exhaust fans, supply fans, return fans, exhaust fans, elevator shaft fans, and other operating equipment used or intended for smoke control purposes. 
Smoke Control On-Auto-Off FAN Switch
Smoke Control On-Auto-Off FAN Switch
  • ON-AUTO-OFF control over individual dampers relating to smoke control and that are controlled from other sources within the building.
Smoke Control On-Auto-Off DAMPER Switch
Smoke Control On-Auto-Off DAMPER Switch
  • ON-OFF or OPEN-CLOSED control over smoke control and other critical equipment associated with a fire or smoke emergency and that can only be controlled from the fire fighters smoke control panel. 
Smoke Control On-Off DOOR Switch
Smoke Control On-Off DOOR Switch

  1. For complex systems (where approved), controls and indicators can be combined to control and indicate all components of a single smoke zone as a single unit. This allows for one switch to control multiple doors, dampers or fans within a single smoke zone. Example: Five dampers on the 10th floor that are all required to close upon smoke mode activation could be controlled and indicated on a single switch with LEDs on the 10th floor of the fire fighter's smoke control panel. 2021 IBC Section 909.16.2

The ON-OFF and OPEN-CLOSE switches shall have the highest priority over any control point within the building. Once automatic or manual control has been initiated from the fire fighter's smoke control panel, any other point in the building shall NOT contradict the control action. The only exception is power disconnects required by NFPA 70 is the only exception.

The AUTO position on three-position switches shall allow automatic or manual control action from other control points within the building. The AUTO position is the normal nonemergency position. 

Fire Fighter's Smoke Control Example

Fire Fighter's Smoke Control Panel
Fire Fighter's Smoke Control Panel

Smoke Control System Response Time

Per 2021 IBC section 909.17, upon receipt of an alarm condition at the fire alarm control panel fans, dampers, and automatic doors shall have achieved their proper operating state and the final status shall be indicated at the smoke control panel within 90 seconds. 

Power Requirements

  • Standby Power Requirements per section 2702.2.17 of the 2021 IBC states that standby power shall be required for smoke control systems per sections 404.7, 909.20.7.2, and 909.21.5.
  • Per section 909.12.1 the smoke control system shall monitor for the presence of power downstream of all disconnects. This will require a monitor module as well as an isolation relay (PR-1 or MR-101) at each power source. Make sure to pay attention to DAMPERS. A lot of the systems today will have a light switch adjacent to the damper actuator for the purpose of dropping power to the unit for service. If this is the case, you will need a monitor module and relay at each of these locations. Pay attention to this when bidding a project as this could potential add quite a few more modules than you may have accounted for.

How are smoke control systems commissioned and tested? 

Per the 2021 International Building Code Section 909.3, smoke control systems shall undergo special inspections and testing in place to verify the proper commissioning of the smoke control design in its final installed condition. As noted above, the rational analysis or smoke control report is required to include procedures that shall be used during the testing and commissioning process. 
  • Per the 2021 IBC, Section 1705.19, Smoke Control Systems shall be tested by a special inspector. 
    • As defined by the 2021 IBC Definitions, a special inspector is a qualified person employed or retained by an approved agency and approved by the building official as having the competence necessary to inspect a particular type of construction requiring special inspection. 
  • Per the 2021 IBC, Section 1705.19.1, the Smoke Control Testing Procedure shall include:
    1. During erection of ductwork and prior to concealment for the purpose of leakage testing and recording of device and equipment locations. This includes but not limited to fans, dampers, smoke detectors, waterflow switches, and verification equipment as outlined above.
    2. Prior to occupancy and after sufficient completion for the purpose of pressure differential testing, air flow measurements and detection and control verification. 
  • Per 2021 IBC, Section 1705.19.2, approved agencies for smoke control testing shall have expertise in fire protection engineering, mechanical engineering, and certification in air balancing. 
  • Per 2021 IBC Section 909.18.8.3, A complete report of testing shall be prepared by the approved agency. The report shall include identification of all devices by manufacturer, nameplate data, design values, measured values, and identification tags. Your hope shall be reviewed by the responsible registered design professional and, when satisfied that the design intent has been achieved the responsible registered design professional shall sign seal and date the reporter.
  • A copy of the final report shall be given to the fire code official along with an identical copy to be filed in an approved location at the facility. 2021 IBC 909.18.3.1.
  • Charts drawings and other documents identifying and locating each component of the small control system as well as describing its proper function and maintenance requirements shall be maintained on file at the building and accompany the report required by section 909.18.8.3. Devices shall have an approved identifying tag on them consistent with the other required documentation and shall be dated indicating the last time they were successfully tested and by whom.
System Acceptance
  • 2021 IBC Section 909.19 states, buildings that are required by this code to employ a smoke control system shall not be issued a certificate of occupancy until such time that the AHJ determines the provisions of chapter 909 have been fully complied with and that the fire department has received ample instruction on the operation both automatic and manual operation of the smoke control system. In addition, a written maintenance program complying with the requirements of section 909.20.1 of the International Fire Code (IFC) has been submitted and approved by the AHJ.

Plan on at least three inspections to commission a smoke control system.

  • Pre-Test the system. Just like a fire alarm system, the sequence and equipment must be ran through prior to calling out the AHJ. The pre-test shall be conducted once all of the power is present, doors are installed, and all fire alarm/smoke control components are in place and programmed per the rational analysis, sequence of operations and approved documentation. Verify all indicators on the fire fighter's smoke control panel as well as manual and automatic operation. 
  • Test with the third-party fire protection firm. Please note this can be the same firm that performed the rational analysis pending they have sufficient training and expertise in testing and commissioning smoke control systems. Depending on the individual conducting the third-party test you may have different requirements. However, you should still run through everything you tested during the pre-test as well as the pre-programmed weekly self-test. At the end of this test, the third party testing firm will issue a report per section 909.18.8.3 and give it to the Fire Code Official. 
  • Final inspection with the AHJ / Fire Code Official. Once the third-party testing firm has issued their report, the AHJ will want to run through a final test. It is up to the AHJ on what will be tested. In my experience, some AHJs will trust the third-party testing firm and perform minimal testing to satisfy their needs. However, some AHJs will want to run through a complete test of all components. Keep this in mind when bidding projects as these tests can take quite a while depending on their complexity. 

Tuesday, February 13, 2024

Duct Smoke Detectors for Supply vs Return - CALIFORNIA

Does California require Duct Smoke Detectors on the Return Side?

Since this question comes up so often, I felt it would be beneficial to put an article together with the answers and applicable code/standard references. Please note that the below information is pertinent to CA and may be altered by individual jurisdictions if they have formally adopted a local ordinance to supersede the state level requirements.

 There are two items to cover with this topic:

  1. In California, are we required to install the duct smoke detector on the supply or return side of HVAC units GREATER than 2,000 cfm?
  2. In California, are we required to install a duct smoke detector on both the supply and return side of and HVAC unit GREATER than 15,000 cfm? 

Before we can answer these questions, we need to know what codes and standards California has adopted. 

Chapter 35 of the California Building Code 2022 edition is dedicated to clarifying which codes and standards are adopted by the State Fire Marshal. The code/standard references are on the left with vertical columns signifying which agencies have adopted them. The third column from the left with the “Xs” is for the State Fire Marshal. From here we can tell that based on the 2022 CBC, the applicable standard for Fire Alarm is the 2022 edition of NFPA 72. Please also note that the IMC or International Mechanical Code is not found within this document.  This lets us know this code not valid in California and therefore its individual language does not apply.

2022 CBC Matrix Adoption Table

Duct Smoke Detectors based on NPFA 72 2022 Edition

 NFPA 72 2022 Section States “To prevent the recirculation of dangerous quantities of smoke, a detector approved for air duct use shall be installed on the supply side of air handing systems as required by NFPA 90A and”

Duct Smoke Detectors based on NFPA 90A

 Since NFPA 90A is referenced in the above NFPA 72 standard, it shall apply. The language for this standard is found in section and reads as follows:

 “Smoke detectors listed for use in air distribution systems shall be located as follows:

  1. Downstream of the air filters and ahead of any ranch connections in air supply systems having a capacity greater than 2000 cfm.
  2. At each story prior to the connection to a common return and prior to any recirculation or fresh air inlet connection in air return systems having a capacity greater than 15,000 cfm and serving more than one story.”

Duct Smoke Detectors based on the International Mechanical Code (IMC)

NO Duct Smoke Detector on Return for units greater than 2,000 cfm in California

 The code that requires a duct smoke detector in the return side of a unit greater than 2,000 cfm is the International Mechanical Code. Keep in mind since this code is not a referenced standard in the California Building Code, it does not apply.

 Section 606.2.1 of the International Mechanical Code states a duct smoke detector shall be installed in return air systems with a deign capacity greater than 2,000 cfm.


  • NFPA 72 2022 - In California we are required to provide a duct smoke detector on the SUPPLY side of HVAC units per NFPA 90A.
  • NFPA 90A - In California we are required to provide a duct smoke detector on the SUPPLY side of HVAC units greater than 2,000 cfm
  • NFPA 90A – In California we are required to provide a duct smoke detector on each return inlet prior to a common return for HVAC units greater than 15,000 which serve more than one floor (below is a simple diagram showing this setup.)
  • IMC 2021 606.2.1 – Requires a duct smoke detector in the return of HVAC units greater than 2,000 cfm. THIS DOES NOT APPLY IN CALIFORNIA
Duct Detectors in Common Return NFPA 90A

Saturday, February 18, 2023

520 Hz Low Frequency for 120VAC Smoke Alarms IFC 2021

How is the new 2021 International Fire Code going to impact your fire alarm design and costs for Group R-1 and R-2 occupancies?

If you install fire alarm system in the residential vertical market, you need to keep reading.

When designing and pricing a new fire alarm system for group R-1 (hotels and motels) and R-2 (apartments, townhomes, and condos) you need to factor in 520Hz low frequency sounders for sleeping rooms. this is found in the 2021 International Fire Code (IFC) and 2022 NFPA 72 standard as follows:

2021 IFC Section 907.
Audible signal frequency in Group R-1 and R-2 occupancies shall be in accordance with Sections 907. and 907.

2021 IFC Section 907.
In sleeping rooms of Group R-1 and R-2 occupancies, the audible alarm activated by the fire alarm system shall be 520-Hz low frequency signal complying with NFPA 72. 

2022 NFPA 72 Section*
Audible appliances provided for the sleeping areas to awaken occupants shall produce a low frequency alarm signal that complies with the following:

(1) The waveform shall have a fundamental frequency of 520 Hz +/- 10 percent.
(2) The notification equipment shall be listed for producing the low frequency waveform.

What does NFPA 72 consider a sleeping area?

To answer this question, you need to consult NFPA 72 2022 Annex A.

"The intent of this section is to require the use of the low frequency signal in areas intended for sleeping and in areas that might reasonably be used for sleeping. For example this section requires a low frequency audible signal in a bedroom of an apartment and also in the living room area of an apartment as it might have sleeping occupants. However, it would not be required to use low frequency signal in the hallways, lobby, an other tenantless spaces. In hotels, the quest rooms would require audible signals could use any listed audible appliances regardless of the frequency content of the signal being produced. This chapter of the code addresses notification appliances connected to and controlled by a fire alarm or emergency communications system. This chapter does not address dwelling unit protection such as smoke alarms and their audible signal characteristics. Requirements for single and multiple station alarms and household fire alarm systems can be found in chapter 29.  

To sum this up, NFPA 72 considers sleeping areas as bedrooms and living rooms.

Up to point, nothing has changed in the way we design and price new fire alarm systems in group R-1 occupancies and group R-2 occupancies. With that being said, lets get to the important code change noted above.

Here is where we get to the update!

2021 International Fire Code (IFC) Section 907.
In sleeping rooms of Group R-1 and R-2 occupancies that are required by Section 907.2.8 or 907.2.9 to have a fire alarm system, the audible alarm signal activated by single or multiple-station smoke alarms in the dwelling unit or sleeping units shall be a 520-Hz signal complying with NFPA 72.

Where a sleeping room smoke alarm is unable to produce a 520-Hz signal, the 520-Hz alarm signal shall be provided by a listed notification appliance or a smoke detector with an integral 520-Hz sounder.

Here is the kicker. There are NO listed 120 VAC single or multiple station smoke alarms on the market with an integral 520 Hz sounder.

We all knew this was coming and surprise, here it is! If we simply the above code language, it states that the 120 VAC single and multiple station smoke alarms of group R-1 and Group R-2 occupancies must now produce a 520 Hz low frequency audible tone


Based on the second paragraph of Section 907., there are two ways to tackle this new requirement:


(1) Use a listed 520 Hz low frequency notification appliance

If this option is selected, you can utilize the wall or ceiling mounted 520 Hz low frequency notification appliances required by the 2021 IFC section 907. for occupant notification in group R-1 and and Group R-2 occupancies. These should already be captured by your minimum code design. However, with a standard design in mind, these appliances will only activate via a general alarm signal. This new 2021 code section 907. is requiring the single and multiple smoke alarms to sound these low frequency appliances. To accomplish this an addressable monitor module could be connected to a contact on the residential unit smoke alarms. This has been done for quite some time in Group R-2 occupancies used for university dorms or specific design criteria such a Marriott's Module 14.  In these cases, the addressable monitor module is in lace to supervise the in room smoke alarms. If these alarms activate, the fire alarm control unit (FACU) would receive a non-latching supervisory alarm without the activation of any occupant notification appliances. To insure the low frequency notification appliances activate via general alarm in addition to in-unit smoke alarm activation,  you would need an addressable control module to isolate each residential units notification appliance circuit (NAC). This way the system can be programmed to activate the in-unit NAC control module upon general alarm (corridor, smoke detectors, elevator lobby smoke detectorss, manual pull stations, waterflow, etc.) or the addressable monitor module connected to the 120 VAC single and multiple station smoke alarms. Remember to program the control module for latching upon general alarm activation and non-latching for the in-unit residential single and multiple station smoke alarms. 

Another scenario that will come up with this approach is audible tones synchroning as well as conflicting tones. If this method is used, an activated smoke alarm would sound it's internal sounder as well as the in room 520 Hz low frequency sounders. This would produce both the standard 3 KHz and 520 Hz tones in the space. Not sure if it is possible to disable the local piezo or sounder on a 120 VAC smoke alarm as this would rectify the conflicting tone issue. To top this off the new 2022 NFPA 72 standard requires audible tones to be synchronized. See section We feel as though this could definitely produce an issue as the audible tones are produced from two different sources. Synchronizing the audible tones may be difficult or impossible.  

Key takeaways for option number one:
  • Requires at least one addressable monitor module for each residential unit.
  • Requires one addressable control module for each residential unit
  • Requires a signaling line circuit (SLC) ran to each residential unit monitor module and control module.
  • Requires a 24VDC power circuit to the addressable control module.
  • Design the system so that each residential unit receives a separate isolated notification appliance circuit (NAC) fed from the control module noted above. 
  • Confirm the electrical contractor is providing 120VAC single and multiple smoke alarms with dry contacts for the the capability to trip the addressable monitor module noted above. 
  • Possible need for additional power supplies and signaling line circuit (SLC) cards depending on the base system.
  • Ensure the audible tones from the single and multiple stations smoke alarm internal piezo and the fire alarm system low frequency Sounders are synchronized. Per 2022 NFPA 72 section
  • Look into the issue of conflicting audible tones. As stated above there may be a method to disable the local piezo or sounder on the single or multiple stations smoke alarms. 

(1) Use an addressable system smoke detector with an integral 520 Hz low frequency sounder base.

If this option is selected for your design, you can replace the standard ceiling or wall mounted 520 Hz low frequency notification appliances with a low frequency sounder base connected to an addressable system smoke detector. As noted above per 2022 NFPA 72 Section A., these smoke detectors and 520 Hz low frequency sounder bases will be required in all sleeping areas which are considered bedrooms and living rooms. Like any other sounder base installation, make sure to account for the addition of a signaling line circuit (SLC) and sounder base notification appliance circuit. With this option, the electrical contractor can remove all power wiring, back boxes and single or multiple smoke alarms from their bid and installation. 

Key takeaways for option number two:
  • Requires at least one addressable smoke detector with integral low frequency sounder base in each bedroom and Livingroom.
  • Requires a signaling line circuit (SLC) ran to each residential unit smoke detector.
  • Requires a 24VDC power circuit or notification appliance circuit (NAC) to the integral low frequency sounder base.
  • Depending on your fire alarm system, you may need end of line power supervision modules to supervise the loss of sounder base power. 
  • Confirm the electrical contractor is NOT providing 120VAC single and multiple smoke alarms, 120 VAC power circuits and back boxes as this will be covered in your fire alarm design. 
  • Possible need for additional power supplies and signaling line circuit (SLC) cards depending on the base system.

Author note: Make sure if option number two is selected for you redesign, you still incorporate the necessary 110CD or 177CD visual appliances in the ADA (Americans with Disabilities Act) units. 

Strobes for ADA residential units

This is a HUGE change to the code and we suggest you start the conversation with your architects, general contractors and electrical contractors so everyone is on the same page moving forward. 

Friday, October 14, 2022

NICET FAS Certifications by State

If you are certified by the National Institute for Certification in Engineering Technologies (NICET) in Fire Alarm Systems (FAS), you may be interested to see how your state ranks up. The cart below has been provided to me by NICET to help show the country how you stack up. I was surprised to see which state came out on top in the most NICET FAS certified technicians. Its also great to see the tail number is up to 17,046 certifier individuals. Keep it up!

Thursday, March 31, 2022

Bluebeam for Fire Alarm Design

 What is Bluebeam?

Bluebeam is a glorified PDF editing software that reaches beyond your expectations. At least in the world of fire alarm design. This software is much like Adobe or Foxit but way more in depth. If setup correctly, Bluebeam can work wonders for your fire alarm take accuracy and efficiency.  

What is different with Bluebeam?

Bluebeam offers and mazing platform that can be setup for quick navigation and access of toolkits, templates, scales and layers. This software allows you to scale a drawing and work with accuracy much like AutoCAD. When laying out a fire alarm system, it is crucial to to make sure your automatic detection initiating devices and notification appliances are spaced properly. When working in scale with custom fire alarm device and notification appliance spacing templates, you can rip though a design in no time at all. 

Did you know the 2021 International Fire Code now requires 120 VAC single and multiple station smoke alarms to produce a 520 Hz low frequency audible tone? 

Bluebeam Software Demonstration

If you are interested in using Bluebeam, I highly recommend watching our YouTube video linked below. This is a quick run through of all the features specific to fire alarm designs and take-offs. 

Bluebeam Profiles and Toolkits

Bluebeam is great in the sense that you can create your own custom profiles and toolkits. Profiles allow you to setup the interface in a way that suits your specific needs Toolkits, allow you to compartmentalize different device and equipment symbols for use in performing take-offs or fire alarm design. If you want to save your self the headache, time and trouble, of creating your own toolkits, we have you covered. The very same setup you saw in our YouTube video are now available for sale right her on our site. 

Bluebeam Profile/Toolkits

Bluebeam Demonstration Video

Wednesday, July 21, 2021

Fire Service Access Elevator FSAE Training Class

Fire Protection Education is hosting a 2 day online virtual seminar covering the new code revisions pertaining to fire service access elevators and occupant evacuation elevators. Read below for a quick overview of the class, pricing, contact info and how to signup.

Fire Service Access Elevator Introduction 

Fire Service Access Elevators or FSAEs were first required in the 2009 edition of the International Building Code or IBC Section 403.6 for all high-rise buildings over 120 feet. At that time only one Fire Service Access Elevator FSAE was required with 3,500lb capacity, serving all floors and sized to accommodate an ambulance stretcher per IBC Section 3002. This was just a standard electric passenger elevator (could not be hydraulic or freight) which was required to serve all floors of the building. This fire service access elevator could have a simplex operation or be a part of a group automatic operation and it required significant building protection around the elevator hoistway and the FSAE car per IBC Section 3007. The building protection features included: large lobbies (150SF in size with a minimum 8 feet dimension), protection of the hoistway and lobbies from Smoke, Heat, Fire and Water, hoistway lighting activated upon fire service activation, pathway survivability for control wires and a monitoring system to monitor the smoke and temperature conditions in the FSAE lobbies and Elevator Machine Room (EMR) or Elevator Control Room (ECR)

This one traction FSAE was just a regular passenger elevator or a service passenger elevator which could be used by the building occupants during the normal operation of the building. 

During fire and non-fire emergencies, the trained firefighters had the ability to choose this elevator for their firefighting emergency operation using Phase II in-car emergency operation. The responding firefighters had available information about the lobbies and EMR/ECR from the FCC and they could make a decision if they want to use this elevator or not to conduct their emergency firefighting and rescue operation. This one elevator had a much greater level of protection than all other elevators in the building and the firefighters were trained to select this specific elevator which was identified with a Fire Helmet symbol on the hoistway door jambs of the FSAE car.

Within the following 4 Code cycles of the IBC (2012, 2015, 2018 and 2021) another FSAE was added and since the 2012 IBC - TWO FSAEs are required in each high-rise building over 120 feet.  This additional FSAE was required for redundancy (in case the other FSAE was out of service or on inspection, etc.) but not for additional firefighting operation. Both FSAEs are required to be sized to accommodate an ambulance stretcher  per Section 3002 and both are required to have 3,500lb capacity.

What is changing with Fire Service Access Elevators?

There are many requirements included in the International Building Code (IBC) regarding these elevators however, no requirements are included for FSAEs in the A17.1/B44 Elevator Safety Code (current edition is 2019). 

The new 2022 edition of the A17.1/B44 will include provisions for the Fire Service Access Elevator FSAE controllers to provide a signal to the building electrical system to activate the FSAE hoistway lights upon Elevator Fire Service (FEO) activation. 

Significant changes are included in the 2021 edition of the IBC and detailed information about the FSAE Lobbies EMR/ECR temperature monitoring system via the building FA system is included in the 2019 edition of NFPA 72 Section 21.5 and A.21.5.

What is changing with Occupant Evacuation Elevators? 

A very significant change regarding the interface between the building fire alarm system and the Occupant Evacuation Elevators (OEE) is included in the 2022 edition of NFPA 72 Section 21.6 which will greatly affect the Fire Alarm system design and interface with the building elevator system.

Class Information

Class is a covered over two sessions as follows:

  • Session #1 (4 Hours): Thursday August 12, 2021 from 9:00am - 1:00pm PST
  • Session #2 (4 Hours): Friday August 13, 2021 from 9:00am - 1:00pm PST
  • Be sure to log in at 8:30am each day to verify connection
  • Course includes PDF color copy of class slides, completion certificate, color PDF flow chart for occupant evacuation elevator and fire alarm sequencing.
ICC Preferred Education Provider
  • ICC Course No 19708
  • Approved for 8 Hours - 0.8 ICC-CEUs
Course cost
  • General Public = $400.00
  • Active AHJs = $350.00
How to enroll

Monday, September 16, 2019

Fire Alarm Wiring Based on NEC Article 760

A common topic for discussion in the fire alarm industry involves fire alarm wiring. This article will cover all aspects of fire alarm wiring including but not limited to separation, conduit fill, strapping, mechanical protection and marking.

Fire Alarm Circuits

Did you know the 2021 International Fire Code now requires 120 VAC single and multiple station smoke alarms to produce a 520 Hz low frequency audible tone? 

The definition of a fire alarm circuit is as follows: "The portion of the wiring system and connected equipment powered and controlled by the fire alarm system. Fire alarm circuits are classified as either nonpower-limited or power-limited."

I'm sure you have heard these two terms in the industry before so let's break them down.

Non-Power Limited Fire Alarm Circuits

A non-power-limited fire alarm circuit commonly referred to as NPLFA, can operate at up to 600V and the power output isn't limited.

Power-Limited Fire Alarm Circuits

A power-limited fire alarm circuit commonly referred to as PLFA, must have the voltage and power limited by a listed power supply that complies with NEC 760.121. Based on this section, a power source can be either (1) a listed PLFA or Class 3 transformer, (2) a listed PLFA or Class 3 power supply or (3) listed equipment marked to identify the PLFA power source. A few examples of listed equipment would be fire alarm control panels with integral power sources and circuit cards listed for use with PLFA sources.

The two tables below provide the listing requirements for power-limited fire alarm circuit sources:

NEC Table 12a and 12b Power Source Limitations

Power Sources for Power-Limited Fire Alarm Circuits

Power-Limited fire alarm equipment must be supplied by a branch circuit that supplies no other load and is NOT GFCI or AFCI protected. The branch circuit overcurrent device (breaker) must be identified in red, accessible only to qualified personnel, and identified as "FIRE ALARM CIRCUIT". The red markings cannot damage the overcurrent protective device or cover any manufacturer's markings. The lock pictured below is available from Space-Age Electronics.

Fire Alarm Circuit Breaker Lock

Equipment Marking for Power-Limited Fire Alarm Circuits

The fire alarm equipment that supplies power-limited fire alarm cable circuits must be marked to indicate each circuit that is a power-limited fire alarm circuit. Per NEC article 760.30, the fire alarm circuits must be marked at terminal and junction locations.

Wiring Methods for Power-Limited Fire Alarm Circuits

Power-limited fire alarm circuits shall be installed in accordance with NEC article 760.46 and conductors shall be solid or stranded copper.

Cable splices or terminations shall be made in listed fittings, boxes, enclosures, fire alarm devices, or utilization equipment. If the circuits are installed exposed, the cables shall be adequately supported and installed in such a manner that maximum protection against physical damage is afforded by building construction. The thought here is that nails from baseboards, door frames, drywall, etc. may penetrate deep enough to damage the wire. To avoid this, make sure to install your fire alarm cables no closer than 1 1/4" from the edge or the framing.  If this is not possible, use 1/16" thick steel plate for protection [NEC 760.24(A)]. Where cables are installed within 7 feet of the floor, said cables shall be fastened in an approved manner at intervals of not more than 18 inches.

steel plate to protect cables in framing

Power-limited fire alarm cables are NOT permitted to be strapped to the exterior of any raceway as a means of support. Exposed cables must be supported by the structural components of a building so that the cable will not be damaged by normal building use. Cables must be supported by straps, staples, hangers, cable ties, or similar fittings designed and installed in a manner that will not dame said cable. If the calves or raceways are installed above a suspended ceiling, they must be supported by independent support wires attached to the suspended ceiling.

Cables passing through a wall or floor. Both Power-Limited and Non Power-Limited Fire Alarm Cables shall be installed in metal raceways or rigid nonmetallic conduit where passing through a floor or wall to a height of 7' above the floor, unless adequate protection an be afforded by building construction. Keep in mind if the cables pass through a fire barrier, you must provide fire caulking to insure the integrity of the barrier.

fire caulk penetration with metal raceway
Fire Caulk Plugs for Cables

Power-Limited Fire Alarm Circuit Separation

This is a topic that a lot of designers and technicians constantly go back and forth on.  To better understand the separation requirements, I believe it is important to know what the 3 different circuit classification are.

Class 1 Circuits. 

Class 1 remote-control and signaling circuits typically operate at 120V, but the NEC permits them to operate at up to 600V [725.21(B)]. You must install these circuits within a wiring method listed in Chapter 3 of the NEC, which includes raceways, cables, and enclosures for splices and terminations [725.25]. Remote-control circuit. These circuits, which control other circuits through relays or equivalent devices, are commonly used to operate motor controllers in moving equipment, mechanical processes, elevators, and conveyors.

Class 2 Circuits.

Class 2 circuits typically include wiring for low-energy (100VA or less), low-voltage (under 30V) loads such as low-voltage lighting, thermostats, PLCs, security systems, and limited-energy voice, intercom, sound, and public address systems. You can also use them for twisted-pair or coaxial local area networks (LAN) [725.41(A)(4)]. Class 2 circuits protect against electrical fires by limiting the power to 100VA for circuits that operate at 30V or less, and 0.5VA for circuits between 30V and 150V.

Class 3 Circuits. 

Class 3 circuits are used when the power demand for circuits over 30V exceeds 0.5VA, but is not more than 100VA [Chapter 9, Table 11]. We often see Class 3 signaling circuits for security systems and public address systems; voice, intercom, and sound systems; and some nurse call systems.
Higher levels of voltage and current are permitted for Class 3 circuits (in contrast to Class 2 circuits).

Fire Alarm Cable Separation based on Circuit Classifications

PLFA with Class 1 Circuits

NEC 760.136 (A) Power-limited fire alarm circuits must not be placed in any enclosure, raceway or cable with conductors of electric light, power or class 1 circuits.

NEC 760.136 (B) If the circuits are separated by a barrier, power-limited fire alarm circuits are permitted with electric power conductors.

NEC 760.136 (D) Power-limited fire alarm circuits can be mixed with electric light, power and class 1 circuits in enclosures where these other conductors are introduced solely for connection to the same equipment and a minimum of 1/4" separation is maintained from the power-limited fire alarm cables.

Power-limited fire alarm circuits shall be separated by not less than 2" from insulated conductors of electric light, power or Class 1 circuits. Exception: If the electric light, power, class 1 circuit or power-limited fire alarm circuits are installed in a raceway, metal-sheathed, metal-clad, nonmetallic-sheathed or underground feeders.

PLFA with Class 2 and Class 3 Circuits

NEC 760.139 (A) Two or more PLFA Circuits. Power-limited fire alarm circuits, communications circuits or Class 3 circuits can be installed in the same cable enclosure, cable tray, raceway or cable routing assembly.

NEC 760.139 (B) PLFA and Class 2 Circuits. Power-limited fire alarm circuits and Class 2 circuits can be within the same cable, cable tray, cable routing assembly, enclosure, or raceway provided the Class 2 circuit insulation is not less than that required for the power-limited fire alarm circuits.

NEC.139 (C) PLFA and Low Power Network Communication. Low-powered network powered broadband communication circuits hall be permitted in the same enclosure, raceway, cable assembly, or cable tray.

NEC 760.139 (D) PLFA and Audio System Circuits. Power-limited fire alarm circuits and audio system circuits using Class 2 and Class 3 wiring methods shall not be installed in the same raceway, enclosure, cable routing assembly or cable tray. Please not this does not apply to voice evacuation and mass notification speaker circuits controlled by a fire alarm control unit or amplifier.

Fire Alarm Cable Substitutions

NEC 760.154(A) The following fire alarm cable substitutions are permitted as long as the wiring requirements of NEC Article 760 Parts I and III apply.

FPLP (Fire Power-Limited Plenum) ------------> CMP
FPLR (Fire Power-Limited Riser) --------------> CMP, FPLP, CMR
FPL (Fire Power-Limited) -----------------------> CMP, FPLP, CMR, FPLR, CMG, CM

Fire Alarm Conductor Size

NEC 760.142. Conductors of 26 AWG shall be permitted only where spliced with a conductor listed as suitable for 26 AWG to 24 AWG or larger conductors that are terminated on equipment or where the 26 AWG conductors are terminated on equipment listed as suitable for 26 AWG conductors.

Single conductors shall NOT be smaller than 18 AWG.

How to Figure Conduit Fill

Conduit fill requirements can be found in the NEC Annex Table C.  This is toward the back of the book and is broken up into different sections based on the type of raceway being used.  In this example, we will use table C.1 for EMT (Electrical Metallic Tubing).  Take a look at the table below and try to locate the maximum number of 14 AWG THHN conductors permitted in 2 1/2" EMT raceway. The answer is 241.