Introduction To Fire Protection System (Theory)

Prioritize safety on the job site to prevent accidents and protect workers and families; major injuries trigger investigations and can pause work for days or months.

Follow safety guides to protect workers. Ensure PPE is provided and worn at all times, stay aware of surroundings, watch for moving parts, hazards, and use tools per manufacturers' guidelines.

Define PPE and explain how protective equipment minimizes exposure to hazards that cause injuries or illness. Examples include gloves, glasses, vest, shoes, helmet, and harness.

Identify common fire symbols in layout drawings, including extinguisher (CO2), hose reel and cabinet, fire pump, risers, breathing inlets, alarm panels, detectors, manual call points, and sprinkler heads.

Explore layout drawings that show the floor plan, room locations, sprinkler placements, and piping connections in fire protection systems.

Examine the dry riser schematic and its breathing inlet to understand how fire protection systems interconnect; the drawing shows interconnections, not layout, and is produced in early design.

Analyze fire behavior using the fire tetrahedron, showing four building blocks: oxygen, heat, fuel, chemical reaction, and how removing any stops combustion. Note the products: flames, heat, and smoke.

Outline the four fire extinguishing methods: cooling, smothering, starvation, and breaking. Explain how each removes a factor of the fire tetrahedron—heat, oxygen, fuel, and chemical reaction.

Explore the four stages of fire—initial, burning, flashover, and decay—and the roles of heat, oxygen, fuel, and chemical reaction in fire progression.

Identify fire classifications by class A, B, C, and D, including ordinary combustibles, flammable liquids, flammable gases, and combustible metals.

Monitor and notify occupants 24 hours a day with a fire alarm system composed of sensors, a fire alarm panel, a voice communication system, and a centralized alarm monitoring station.

Explore fire detection using heat, smoke, and radiation sensors to detect fires before and after ignition, and learn when to combine smoke, heat, and radiation detectors in high risk areas.

Decentralized alarm monitoring relays verified signals from the main fire alarm panel to the EMS station before notifying the fire department, reducing false alarms.

The fire alarm panel receives information from sensors across the building, controls and transmits it, and uses a dedicated primary power supply with a secondary backup capable of 24 hours.

Explore the supervised fire alarm circuit, including end-of-line resistors and current paths under normal and fire conditions. Understand how short and open circuits affect signaling.

Explore class a and class b fire alarm wiring. Class a maintains detector connectivity to panel through a loop, while class b is cheaper and limits monitoring after a break.

Compare main and sub alarm panels, main in the fcc room and sub in its zones, and how the SAP alarm panel collects signals from sensors and call points.

Explore the addressable alarm panel and its intelligence over conventional systems, showing how addressable detectors are numbered and provide data such as smoke density or heat-detector temperature.

Compare addressable and conventional alarm panels: addressable panels report on individual detectors and cost more, suited to large buildings; conventional panels report on zones and are cheaper for small buildings.

Explore conventional and addressable fire alarm panel catalogs, detailing 230v mains, battery backup, zone options (2–8), addressable loops (1–8), fire-resistant cabling, detectors, and an RS485 connector.

Learn how heat detectors detect heat from a fire and why they are reliable yet slower than smoke detectors, making them less suitable for early detection in computer rooms.

Explain fixed temperature heat detectors, which sense heat at a set threshold (such as 55°C) and trigger an alarm once exceeded, with slower response than rate-of-rise detectors.

Explore how the rate of rise heat detector detects temperature rising at about 7–8 degrees per minute to trigger an alarm, delivering a faster response than fixed temperature detectors.

Learn to test and inspect heat detectors, ensuring at least 20 percent are tested yearly and units within five years, not exceeding 40 detectors per zone, using a hair dryer.

Explore the Demko heat detector, a combined rate-of-rise and fixed-temperature device with an led indicator, that triggers at 6°C in four seconds and is factory calibrated for 12–28 v dc.

Explore how smoke detectors provide early fire warnings with faster response than heat detectors, discuss two types, photoelectric and ionization, and note their potential for false alarms.

Explain how photoelectric smoke detectors use a light beam and smoke to trigger alarms, covering light obscuring and light scattering types.

Light obscuring smoke detectors use a light beam and receiver; smoke blocks the beam, triggering an alarm, often installed in high ceiling areas such as atriums and warehouses.

Explain how a light scattering smoke detector uses refracted light to trigger an alarm when smoke is present, contrasting with normal conditions where no light reaches the receiver.

Explore how ionization smoke detectors use two electrodes and a radioactive material to ionize air, create a current between plates, and trigger an alarm when smoke lowers the current.

Explore the disadvantages of smoke detectors, including false alarms from smoking and cooking, and how ventilation can blow smoke away, delaying alarm response times.

Learn to test and inspect smoke detectors according to country standards, targeting at least 20% inspections and ensuring that after five years all detectors have been inspected.

Explore a Demko photoelectric smoke detector with 360-degree sensing, easy installation, and a pulsing LED, and learn how UL and CE certifications verify safety and European compliance.

Explains how flame detectors trigger alarms by detecting radiation from flames, not smoke or temperature changes. Introduces two types, UV and IR detectors.

Examine the disadvantages of ultraviolet and infrared detectors, including false alarms from welding and sunlight, and the effects of smoke and air on detection capabilities.

Explore infrared detectors that use a photo electric cell to sense infrared radiation, with a built-in timer to prevent false alarms.

Explore ultraviolet detectors that use a gas-filled tube to detect ultraviolet radiation. These detectors differentiate flame radiation from sunlight by responding to specific wavelengths.

the lesson explains the disadvantages of uv and ir detectors in fire protection, including false alarms from welding and sunlight, and interference from smoke and air.

Explore the flame detector catalog for a combined UV and IR detector, indoor and outdoor use, with three LED indicators, a test lab accessory, and UV wavelength specs.

Learn how a manual call point, also called a pull box or pull station, triggers an alarm by breaking the glass and pressing a button to notify occupants.

Explore how alarm bells emit audible signals and strobe lights provide visual signals to notify occupants, with 65 dba above normal noise levels, and synchronized flashing for accessibility.

Explore a sample Demko fire alarm bell catalog and strobe lights, highlighting outdoor weatherproof designs, corrosion resistance, decibel ranges from 83–95 and 68–100, and four alarm tones.

Discover how the hose reel acts as immediate fire response equipment for occupants during the initial stage, highlighting ease of use and the rule to escape, not fight, large fires.

Explore the two hose reel types: swinging hose reels that swing left or right, and fixed hose reels that stay stationary.

Describe hose reel characteristics, including a 30 m length, nozzle options of 4 or 6 m, and the ability to shoot water to at least 10 m.

Learn how a hose reel water supply can source water from a cistern, at low or high level, and tap into the sprinkler system’s supply side.

Assess hose reel testing and inspection, ensuring drum rotation is under 200 newtons, no leaks, and no damage; conduct flow rate and pressure tests at the highest and furthest point.

Explore the swing type hose reel catalog from Demko, noting 30 m length, 11.2 m throw range, and 6 mm nozzle, with cabinet dimensions and epoxy-coated mild or stainless steel.