National electrical code article 760 – National Electrical Code (NEC) Article 760 serves as the cornerstone for ensuring the safety and effectiveness of fire alarm systems. This comprehensive guide delves into the intricate details of Article 760, providing a thorough understanding of its purpose, scope, and applications.

NEC Article 760 establishes stringent requirements for the design, installation, and maintenance of fire alarm systems, ensuring their reliability in detecting and alerting occupants to potential fire hazards. By adhering to these guidelines, professionals can ensure that fire alarm systems function optimally, safeguarding lives and property.

NEC Article 760 Overview

NEC Article 760, titled “Fire Pumps,” addresses the electrical requirements for fire pumps, which are essential for providing water to fire suppression systems. The article’s primary objective is to ensure the reliability and effectiveness of fire pumps during emergency situations.

Article 760 is applicable to electrical installations associated with fire pumps, including power sources, controllers, wiring, and other electrical components. It covers both new and existing installations, and it applies to all types of buildings and structures where fire pumps are required.

Typical Applications

Typical applications where Article 760 is relevant include:

• Commercial buildings (e.g., offices, shopping malls, hotels)
• Industrial facilities (e.g., factories, warehouses, power plants)
• Healthcare facilities (e.g., hospitals, clinics, nursing homes)
• Educational institutions (e.g., schools, universities, libraries)
• Residential buildings (e.g., apartment complexes, condominiums, townhouses)

Fire Alarm Systems

Fire alarm systems are an essential part of any building’s fire safety system. They provide early warning of a fire, giving occupants time to evacuate the building and firefighters time to respond. Fire alarm systems must be designed and installed in accordance with the National Electrical Code (NEC) Article 760.NEC

Article 760 provides detailed requirements for the design and installation of fire alarm systems. These requirements cover everything from the type of detectors to be used to the wiring and installation methods. The NEC also requires that fire alarm systems be inspected and tested on a regular basis to ensure that they are in good working order.There

are many different types of fire alarm systems available, each with its own advantages and disadvantages. The most common type of fire alarm system is the conventional system. Conventional systems use a single zone to monitor the entire building. If a fire is detected in any part of the building, the system will sound an alarm throughout the entire building.Addressable

systems are another type of fire alarm system. Addressable systems use a series of detectors that are each assigned a unique address. When a fire is detected, the system will sound an alarm and display the address of the detector that detected the fire.

This allows firefighters to quickly locate the fire and begin firefighting operations.Wireless fire alarm systems are a newer type of fire alarm system that uses wireless technology to transmit signals between the detectors and the control panel. Wireless systems are less expensive to install than wired systems, and they can be installed in buildings where it is difficult to run wires.When

selecting a fire alarm system, it is important to consider the size and layout of the building, the type of occupancy, and the budget. It is also important to consult with a qualified fire alarm contractor to ensure that the system is properly designed and installed.Fire

alarm systems are an important part of any building’s fire safety system. By following the requirements of NEC Article 760, building owners and managers can help to ensure that their buildings are protected from fire.

Types of Fire Alarm Systems

There are many different types of fire alarm systems available, each with its own advantages and disadvantages. The most common type of fire alarm system is the conventional system. Conventional systems use a single zone to monitor the entire building.

If a fire is detected in any part of the building, the system will sound an alarm throughout the entire building.Addressable systems are another type of fire alarm system. Addressable systems use a series of detectors that are each assigned a unique address.

When a fire is detected, the system will sound an alarm and display the address of the detector that detected the fire. This allows firefighters to quickly locate the fire and begin firefighting operations.Wireless fire alarm systems are a newer type of fire alarm system that uses wireless technology to transmit signals between the detectors and the control panel.

Wireless systems are less expensive to install than wired systems, and they can be installed in buildings where it is difficult to run wires.The type of fire alarm system that is best for a particular building will depend on the size and layout of the building, the type of occupancy, and the budget.

Fire Alarm System Components, National electrical code article 760

Fire alarm systems are made up of a number of different components, including:* Detectors: Detectors are the devices that detect the presence of fire. There are many different types of detectors available, including smoke detectors, heat detectors, and flame detectors.

Control panel

The control panel is the central brain of the fire alarm system. It receives signals from the detectors and activates the alarm when a fire is detected.

Alarm devices

Alarm devices are the devices that sound the alarm when a fire is detected. Alarm devices can include bells, sirens, and strobes.

Wiring

The wiring connects the detectors, control panel, and alarm devices.It is important to ensure that all of the components of a fire alarm system are properly installed and maintained. A properly installed and maintained fire alarm system can help to protect lives and property from fire.

Notification Appliances

Notification appliances are devices that alert occupants of a fire or other emergency. They can be used to evacuate buildings, direct people to safety, and provide information about the emergency. There are many different types of notification appliances, each with its own advantages and disadvantages.

The most common type of notification appliance is the audible alarm. Audible alarms produce a loud sound that can be heard from a distance. They are typically used in areas where people are likely to be present, such as hallways, stairwells, and common areas.

Audible alarms can be either continuous or intermittent. Continuous alarms produce a constant sound, while intermittent alarms produce a pulsed sound.

Visual alarms are another common type of notification appliance. Visual alarms produce a flashing light that can be seen from a distance. They are typically used in areas where people may not be able to hear an audible alarm, such as in noisy environments or in areas where people are deaf or hard of hearing.

Visual alarms can be either steady or flashing.

Tactile alarms are a type of notification appliance that produces a vibration. Tactile alarms are typically used in areas where people may not be able to hear an audible alarm or see a visual alarm, such as in areas where people are blind or deaf-blind.

Tactile alarms can be either continuous or intermittent.

Requirements for Installing and Testing Notification Appliances

The National Fire Protection Association (NFPA) has established requirements for the installation and testing of notification appliances. These requirements are designed to ensure that notification appliances are installed and tested in a way that will maximize their effectiveness in alerting occupants of a fire or other emergency.

The NFPA 72 National Fire Alarm and Signaling Code requires that notification appliances be installed in all areas of a building where people are likely to be present. The code also requires that notification appliances be tested on a regular basis to ensure that they are functioning properly.

Examples of Different Notification Appliances and Their Applications

There are many different types of notification appliances available, each with its own advantages and disadvantages. The following are some examples of different notification appliances and their applications:

• Audible alarmsare the most common type of notification appliance. They are typically used in areas where people are likely to be present, such as hallways, stairwells, and common areas.
• Visual alarmsare another common type of notification appliance. They are typically used in areas where people may not be able to hear an audible alarm, such as in noisy environments or in areas where people are deaf or hard of hearing.

• Tactile alarmsare a type of notification appliance that produces a vibration. Tactile alarms are typically used in areas where people may not be able to hear an audible alarm or see a visual alarm, such as in areas where people are blind or deaf-blind.

• Mass notification systemsare a type of notification appliance that can be used to send alerts to a large number of people. Mass notification systems are typically used in areas where there is a need to evacuate a large number of people quickly, such as in schools, hospitals, and office buildings.

Control Units

Fire alarm control units are the brains of a fire alarm system. They receive signals from fire detectors and other initiating devices, process the information, and activate the appropriate notification appliances and other system components. Control units also provide power to the system and monitor its operation.

There are two main types of fire alarm control units: conventional and addressable. Conventional control units are less expensive and easier to install than addressable control units, but they offer less flexibility and functionality. Addressable control units can be programmed to identify the specific location of a fire, which can be helpful in large buildings or complexes.

When selecting a fire alarm control unit, it is important to consider the size and complexity of the building, the number of fire detectors and other initiating devices that will be connected to the system, and the desired level of functionality.

It is also important to ensure that the control unit is compatible with the other components of the fire alarm system.

Installation

Fire alarm control units must be installed in accordance with the manufacturer’s instructions and the requirements of the local building code. The control unit should be located in a central location that is accessible to authorized personnel. It should also be protected from damage and tampering.

The control unit should be connected to the fire alarm system’s power supply and to the initiating devices and notification appliances. The control unit should also be connected to a telephone line so that it can report alarms to a central monitoring station.

Maintenance

Fire alarm control units should be inspected and tested regularly to ensure that they are operating properly. The inspection and testing should be performed by a qualified technician in accordance with the manufacturer’s instructions and the requirements of the local building code.

Initiating Devices

Initiating devices are crucial components of fire alarm systems, designed to detect the presence of fire or smoke and trigger the activation of the alarm system. These devices play a vital role in ensuring the timely detection and notification of a fire emergency.Initiating

devices can be classified into two main categories: manual and automatic. Manual initiating devices, such as pull stations and break-glass stations, require human activation to initiate the alarm. Automatic initiating devices, on the other hand, operate autonomously when they sense specific environmental conditions, such as smoke, heat, or flame.

Smoke Detectors

Smoke detectors are the most common type of automatic initiating device used in fire alarm systems. They operate by detecting the presence of smoke particles in the air, which can indicate the presence of a fire. Smoke detectors can be classified into two main types: ionization and photoelectric.*

Ionization smoke detectorsuse a radioactive source to ionize the air inside the detector chamber. When smoke particles enter the chamber, they disrupt the ionization process, causing a decrease in the electrical current. This decrease in current triggers the alarm. Photoelectric smoke detectorsuse a light source and a photocell to detect smoke particles.

When smoke particles enter the chamber, they scatter the light, causing less light to reach the photocell. This decrease in light intensity triggers the alarm.

Heat Detectors

Heat detectors are another common type of automatic initiating device used in fire alarm systems. They operate by detecting an increase in temperature, which can indicate the presence of a fire. Heat detectors can be classified into two main types: fixed-temperature and rate-of-rise.*

Fixed-temperature heat detectorsare designed to trigger the alarm when the temperature reaches a predetermined level.

Rate-of-rise heat detectorsare designed to trigger the alarm when the temperature rises at a predetermined rate.

Flame Detectors

Flame detectors are used to detect the presence of open flames. They operate by sensing the ultraviolet or infrared radiation emitted by flames. Flame detectors are often used in areas where there is a high risk of fire, such as industrial facilities and chemical plants.

Other Initiating Devices

In addition to smoke detectors, heat detectors, and flame detectors, there are a variety of other initiating devices that can be used in fire alarm systems. These devices include:* Manual pull stations: These devices are activated by pulling a lever or handle, which triggers the alarm.

Break-glass stations

These devices are activated by breaking a glass panel, which triggers the alarm.

Waterflow switches

These devices are activated when water flows through a sprinkler system, which triggers the alarm.

Carbon monoxide detectors

These devices detect the presence of carbon monoxide, which can be a byproduct of combustion.

Requirements for Installing and Testing Initiating Devices

The National Electrical Code (NEC) provides specific requirements for the installation and testing of initiating devices in fire alarm systems. These requirements are designed to ensure that the devices are properly installed and maintained, so that they will function reliably in the event of a fire.Some

of the key requirements for installing initiating devices include:* Initiating devices must be located in accordance with the manufacturer’s instructions.

• Initiating devices must be installed in a manner that will prevent accidental activation.
• Initiating devices must be tested regularly to ensure that they are functioning properly.

Examples of Different Initiating Devices and Their Applications

The following are some examples of different initiating devices and their applications:* Smoke detectorsare used in a wide variety of applications, including residential, commercial, and industrial buildings.

• Heat detectorsare often used in areas where there is a high risk of fire, such as kitchens, garages, and workshops.
• Flame detectorsare used in areas where there is a high risk of open flames, such as industrial facilities and chemical plants.
• Manual pull stationsare often used in areas where there is a high risk of human activity, such as schools, hospitals, and office buildings.
• Break-glass stationsare often used in areas where there is a high risk of vandalism, such as parking garages and public restrooms.

Power Sources

Fire alarm systems rely on reliable power sources to operate effectively. The National Electrical Code (NEC) provides specific requirements for power sources used in these systems to ensure their proper functioning during an emergency.

There are two primary types of power sources for fire alarm systems: primary and secondary.

Primary Power Sources

Primary power sources are the main source of power for fire alarm systems. They are typically connected to the building’s electrical system and provide continuous power to the system.

Primary power sources must be capable of providing the required voltage and current for the fire alarm system. They must also be able to maintain power for a minimum of 24 hours in the event of a power outage.

Secondary Power Sources

Secondary power sources provide backup power to fire alarm systems in the event of a primary power failure. They are typically batteries or generators.

Secondary power sources must be capable of providing the required voltage and current for the fire alarm system for a minimum of 24 hours. They must also be able to recharge automatically when primary power is restored.

Selecting and Installing Power Sources

When selecting and installing power sources for fire alarm systems, it is important to consider the following factors:

• The size and complexity of the fire alarm system
• The location of the fire alarm system
• The availability of reliable primary and secondary power sources

It is also important to follow the manufacturer’s instructions for installing and maintaining power sources for fire alarm systems.

Testing and Maintenance: National Electrical Code Article 760

Maintaining fire alarm systems in good working order is critical for ensuring they function properly in the event of a fire. The National Electrical Code (NEC) requires that fire alarm systems be tested and maintained regularly to ensure they are in good working order.

The frequency of testing and maintenance will vary depending on the type of fire alarm system and the environment in which it is installed. However, all fire alarm systems should be tested and maintained at least annually.

Types of Tests

There are several different types of tests that should be performed on fire alarm systems. These tests include:

• Functional tests: Functional tests verify that all components of the fire alarm system are working properly. This includes testing the power supply, the control unit, the initiating devices, and the notification appliances.
• Drill tests: Drill tests simulate a real fire by activating the fire alarm system and requiring occupants to evacuate the building. Drill tests help to ensure that occupants are familiar with the fire alarm system and that they know what to do in the event of a fire.

• Maintenance tests: Maintenance tests are performed to ensure that the fire alarm system is in good working order and that there are no problems that could prevent it from functioning properly. Maintenance tests include checking the power supply, the control unit, the initiating devices, and the notification appliances.

Developing a Testing and Maintenance Schedule

It is important to develop a testing and maintenance schedule for your fire alarm system. This schedule should be based on the type of fire alarm system and the environment in which it is installed. The schedule should include the following information:

• The frequency of testing and maintenance
• The type of tests that will be performed
• The person or company who will perform the testing and maintenance

By following these requirements, you can help to ensure that your fire alarm system is in good working order and that it will function properly in the event of a fire.

Questions Often Asked

What is the purpose of NEC Article 760?

NEC Article 760 establishes the minimum requirements for the design, installation, and maintenance of fire alarm systems, ensuring their effectiveness in detecting and alerting occupants to fire hazards.

What types of electrical installations are covered by NEC Article 760?

NEC Article 760 applies to all electrical installations that include fire alarm systems, regardless of the type of building or occupancy.

What are the key components of a fire alarm system?

Fire alarm systems typically consist of initiating devices (e.g., smoke detectors), notification appliances (e.g., horns and strobes), control units, and power sources.