Fire Detection and Suppression Chapter 1 Fire Extinguishing

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Fire Detection and Suppression Chapter 1 Fire Extinguishing Agents and Portable Fire Extinguishers

Fire Detection and Suppression Chapter 1 Fire Extinguishing Agents and Portable Fire Extinguishers

Portable Fire Extinguishers • First line of defense against incipient fires of limited size

Portable Fire Extinguishers • First line of defense against incipient fires of limited size • For a portable extinguisher to be effective, the following requirements must be met: — Extinguisher must be readily accessible. — Extinguisher must be in working order. — Extinguisher must be suitable for the hazard — Operator must know how to use extinguisher. 1 Fire Extinguishing Agents and Portable Fire Extinguishers

Classification of Fires by Burning Characteristics • Class A: ordinary combustibles • Class B:

Classification of Fires by Burning Characteristics • Class A: ordinary combustibles • Class B: flammable and combustible liquids and gases • Class C: energized electrical equipment • Class D: combustible metals • Class K: cooking devices that contain or use combustible vegetable or animal oils and fats 2 Fire Extinguishing Agents and Portable Fire Extinguishers

Extinguisher Symbols • Pictorial system (Fig. 1. 2) • Letter system (Table 1. 1)

Extinguisher Symbols • Pictorial system (Fig. 1. 2) • Letter system (Table 1. 1) 3 Fire Extinguishing Agents and Portable Fire Extinguishers

How Extinguishers Are Rated • UL 711, Standard For Rating and Fire Testing Fire

How Extinguishers Are Rated • UL 711, Standard For Rating and Fire Testing Fire Extinguishers • Rating criteria — Intended use (fire class) — Fire fighting capability – Volume and duration of agent discharge – Range of discharge – Hydrostatic testing of the agent vessel and discharge hose 4 Fire Extinguishing Agents and Portable Fire Extinguishers

Extinguisher Rating Tests • Class A — Wood crib test — Wood panel test

Extinguisher Rating Tests • Class A — Wood crib test — Wood panel test — Excelsior test • Class B: 2 -inch (50 mm) layer of flammable liquid • Class C: nonconductivity (Continued) 5 Fire Extinguishing Agents and Portable Fire Extinguishers

Extinguisher Rating Tests (cont. ) • Class D: tested for specific types of metals

Extinguisher Rating Tests (cont. ) • Class D: tested for specific types of metals — Magnesium fire tests — Sodium And Potassium Fire Tests • Class K: UL Standard 300 6 Fire Extinguishing Agents and Portable Fire Extinguishers

Extinguishing Agents • Water • Antifreeze agents • Alkaline mixtures • Carbon dioxide (CO

Extinguishing Agents • Water • Antifreeze agents • Alkaline mixtures • Carbon dioxide (CO 2) • Aqueous film forming foam (AFFF) • Film forming fluoroprotein (FFFP) (Continued) 7 Fire Extinguishing Agents and Portable Fire Extinguishers

Extinguishing Agents (cont. ) • Halogenated agents • Halotron and other replacement agents •

Extinguishing Agents (cont. ) • Halogenated agents • Halotron and other replacement agents • Dry chemical agents — Ordinary – Sodium bicarbonate – Potassium bicarbonate — Multipurpose: monoammonium phosphate — Class D dry powders: NA-X; Met-L-X; Lith-X 8 Fire Extinguishing Agents and Portable Fire Extinguishers

Types of Fire Extinguishers • Stored-pressure • Cartridge-operated • Pump-operated • Obsolete types —

Types of Fire Extinguishers • Stored-pressure • Cartridge-operated • Pump-operated • Obsolete types — Inverting — Soldered or riveted shell — Loaded stream 9 Fire Extinguishing Agents and Portable Fire Extinguishers

Selection and Distribution of Extinguishers (cont. ) • General considerations — Nature of the

Selection and Distribution of Extinguishers (cont. ) • General considerations — Nature of the hazard — Size of the extinguisher – Light hazard occupancy – Ordinary hazard occupancy – Extra hazard occupancy (Continued) 10 Fire Extinguishing Agents and Portable Fire Extinguishers

Selection and Distribution of Extinguishers (cont. ) • Specific considerations — Chemical and physical

Selection and Distribution of Extinguishers (cont. ) • Specific considerations — Chemical and physical characteristics of combustibles — Potential severity of fire — Location of extinguisher — Effectiveness of the extinguisher for the hazard — Personnel available to operate the extinguisher — Environmental conditions (Continued) 11 Fire Extinguishing Agents and Portable Fire Extinguishers

Selection and Distribution of Extinguishers • Specific considerations (cont. ) — Anticipated adverse chemical

Selection and Distribution of Extinguishers • Specific considerations (cont. ) — Anticipated adverse chemical reactions between the extinguishing agent and the burning material — Any health and occupational safety concerns — Inspection and service required (Continued) 12 Fire Extinguishing Agents and Portable Fire Extinguishers

Selection and Distribution of Extinguishers (cont. ) • Class A extinguisher distribution factors; substitutions

Selection and Distribution of Extinguishers (cont. ) • Class A extinguisher distribution factors; substitutions in ordinary- and low-hazard occupancies • Class B extinguisher distribution factors — Distance to hazard — Depth of hazard – Flammable liquid fires without depth – Flammable liquid fires with depth (Continued) 13 Fire Extinguishing Agents and Portable Fire Extinguishers

Selection and Distribution of Extinguishers (cont. ) • Class C extinguisher distribution factors :

Selection and Distribution of Extinguishers (cont. ) • Class C extinguisher distribution factors : — No special rules — Usually involve Class A or Class B fuels • Class D extinguisher distribution factors : — Requires analysis of specific metal present — Travel distance should not exceed 75 feet (25 m) (Continued) 14 Fire Extinguishing Agents and Portable Fire Extinguishers

Selection and Distribution of Extinguishers (cont. ) • Class K extinguisher distribution factors —

Selection and Distribution of Extinguishers (cont. ) • Class K extinguisher distribution factors — Employee responsibilities — Travel distance should not exceed 30 feet (10 m) 15 Fire Extinguishing Agents and Portable Fire Extinguishers

Installation and Placement of Extinguishers • General guidelines — Visible and well signed —

Installation and Placement of Extinguishers • General guidelines — Visible and well signed — Not blocked by storage or equipment — Near points of egress or ingress — Near normal paths of travel (Continued) 16 Fire Extinguishing Agents and Portable Fire Extinguishers

Installation and Placement of Extinguishers (cont. ) • Installation guidelines — Height from floor

Installation and Placement of Extinguishers (cont. ) • Installation guidelines — Height from floor — Temperature of environment — Snow, rain, corrosive fumes 17 Fire Extinguishing Agents and Portable Fire Extinguishers

Portable Fire Extinguishers on Fire Apparatus • General requirements: — Proper type for probable

Portable Fire Extinguishers on Fire Apparatus • General requirements: — Proper type for probable hazards — Accessible — Proper maintenance • NFPA 1901, Standard on Automotive Fire Apparatus (Continued) 18 Fire Extinguishing Agents and Portable Fire Extinguishers

Inspecting, Maintaining, and Recharging Extinguishers • Infrequent use results in tendency to ignore extinguishers

Inspecting, Maintaining, and Recharging Extinguishers • Infrequent use results in tendency to ignore extinguishers • Common problems — Misplaced or stolen extinguishers — Damage from being struck by vehicle — Lost pressure — Extinguishers used and replaced without notifying proper authorities (Continued) 19 Fire Extinguishing Agents and Portable Fire Extinguishers

Inspecting, Maintaining, and Recharging Extinguishers (cont. ) • Inspection: visual check to determine that

Inspecting, Maintaining, and Recharging Extinguishers (cont. ) • Inspection: visual check to determine that an extinguisher is available and operable • Maintenance: thorough examination and performance of any needed service 20 Fire Extinguishing Agents and Portable Fire Extinguishers

Inspecting Extinguishers • Check that the extinguisher is in its proper location. • Ensure

Inspecting Extinguishers • Check that the extinguisher is in its proper location. • Ensure that access to the extinguisher is not obstructed by boxes, clothing, storage items, or is otherwise inaccessible. • Check the inspection tag to determine if maintenance is due. (Continued) 21 Fire Extinguishing Agents and Portable Fire Extinguishers

Inspecting Extinguishers (cont. ) • Examine the nozzle or horn for obstructions. • Check

Inspecting Extinguishers (cont. ) • Examine the nozzle or horn for obstructions. • Check lock pins or tamper seals to make sure that they are intact. • Check for signs of physical damage. • Check that the extinguisher is full of agent. • Check that the pressure gauge indicates proper reading. (Continued) 22 Fire Extinguishing Agents and Portable Fire Extinguishers

Inspecting Extinguishers (cont. ) • Check collar tag for current information and/or damage. •

Inspecting Extinguishers (cont. ) • Check collar tag for current information and/or damage. • Check that required signage is in place. • Check to see if the operating instructions on the extinguisher nameplate are legible. • Check that the extinguisher is suitable for the hazard protected. 23 Fire Extinguishing Agents and Portable Fire Extinguishers

Maintaining Extinguishers • Mechanical parts • Extinguishing agent • Expelling means 24 Fire Extinguishing

Maintaining Extinguishers • Mechanical parts • Extinguishing agent • Expelling means 24 Fire Extinguishing Agents and Portable Fire Extinguishers

Recharging Extinguishers • Importance of following correct schedule • Using proper extinguishing agent •

Recharging Extinguishers • Importance of following correct schedule • Using proper extinguishing agent • Pressurizing • Moisture contamination in nonwater extinguishers • Qualifications and training 25 Fire Extinguishing Agents and Portable Fire Extinguishers

Hydrostatic Testing of Portable Extinguishers • Failure of pressure vessels • Hydrostatic test: filling

Hydrostatic Testing of Portable Extinguishers • Failure of pressure vessels • Hydrostatic test: filling the cylinder with water and then applying appropriate pressure by means of a pump — Determining appropriate pressure — Signs that preclude testing an extinguisher — Record keeping 26 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers Step 1: Activate alarm system. First, call appropriate fire department. Second,

Using Portable Extinguishers Step 1: Activate alarm system. First, call appropriate fire department. Second, initiate local alarm. Step 2: Select a suitable extinguisher. Match extinguisher to fire. Analyze the type of hazard being protected and provide, in a conspicuous location, an extinguisher of the proper size and type. (Continued 27 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers Step 3: Activate the extinguisher effectively. Stored pressure: remove safety pin

Using Portable Extinguishers Step 3: Activate the extinguisher effectively. Stored pressure: remove safety pin and squeeze valve handle. Cartridge: remove nozzle from holder and depress lever that punctures cartridge seal. Step 4: Apply the extinguishing agent properly. (Continued) 28 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers (cont. ) • P. A. S. S. Method — Pull the

Using Portable Extinguishers (cont. ) • P. A. S. S. Method — Pull the pin — Aim — Squeeze — Sweep (Continued) 29 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers (cont. ) • Attacking Class A fires — Water-based extinguisher –

Using Portable Extinguishers (cont. ) • Attacking Class A fires — Water-based extinguisher – Aim stream at seat of fire – Initial distance = 10– 30 feet (3 m to 10 m) — AFFF extinguisher: same method as water-based — Multipurpose dry chemical – Attack fire at base – Sweep nozzle from side to side – Coat all fuel surfaces (Continued) 30 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers (cont. ) • Attacking Class B fires — Regular or multipurpose

Using Portable Extinguishers (cont. ) • Attacking Class B fires — Regular or multipurpose dry chemical extinguishers – Begin discharge at about 10 feet (3 m), sweeping leading edge of fire and moving forward. – Begin second attacks with second full extinguishers. — C 02 extinguishers – Apply at close range, sweeping surface of burning liquid with overlapping strokes. – Continue discharge after initial extinguishment (Continued) 31 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers (cont. ) • Attacking Class C fires — Dielectric or nonconductive

Using Portable Extinguishers (cont. ) • Attacking Class C fires — Dielectric or nonconductive agent – Carbon dioxide* – Water mist* – Halon – Dry chemical (involves substantial cleanup) *Best choices — De-energize equipment if possible (Continued) 32 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers (cont. ) • Attacking Class D fires — Dry powder agents

Using Portable Extinguishers (cont. ) • Attacking Class D fires — Dry powder agents – Apply with extinguisher or shovel – Cover fuel with 2 -inch layer – Avoid disturbing fuel — Limitations of individual agents (Continued) 33 Fire Extinguishing Agents and Portable Fire Extinguishers

Using Portable Extinguishers (cont. ) • Attacking Class K fires — Class K fire

Using Portable Extinguishers (cont. ) • Attacking Class K fires — Class K fire extinguisher recommended — Class A: B: C or Class B: C extinguisher: reignition possible — Application – Begin from distance of 10 to 12 feet (3. 5 – 4 m) – Hold application wand at edge of flames and coat surface of fuel with side-to-side sweep. – Continue to apply agent until the fire extinguisher is completely empty. 34 Fire Extinguishing Agents and Portable Fire Extinguishers