Chapter 12 Systems and Equipment for Fire Protection

Introduction Water is the most common extinguishing agent used for combating fires Automatic firefighting devices have been developed to aid in the application of water and other firefighting agents In occupancies or applications where water may cause damage or be ineffective, other extinguishing agents have been developed

WATER SUPPLY SYSTEM All systems must have storage capability Capacity and adequacy Adequacy gauged in several areas  Average daily consumption  Maximum daily consumption  Peak hourly consumption Learning Objective 1 Components of a Water Supply System

DISTRIBUTION SYSTEM Underground piping called water mains Largest are primary feeders Intermediate are secondary feeders Distributor piping Common sizes are 8, 12, and 16 inch Learning Objective 1 Components of a Water Supply System

TYPES OF HYDRANTS IN USE TODAY Wet barrel hydrant Dry barrel hydrant Dry hydrant Hydrant installation Cont. Learning Objective 1 Components of a Water Supply System

TYPES OF HYDRANTS IN USE TODAY Airport or special property Complete prefire program Flushing hydrants Hydrant testing Hydrant painting Learning Objective 1 Components of a Water Supply System

Learning Objective 2 Importance of Dependable Water Supply System PUBLIC WATER COMPANIES Set up under public utility laws Provide for everyday needs of customers Usually have elected officials to administrate PRIVATE WATER COMPANIES Maintain their own distribution and storage equipment

WATER SYSTEMS PROGRAM Letter of working agreement Grid map Hydrant survey and service records Preplanning Cont. Learning Objective 3 Components of Water Supply Program

WATER SYSTEMS PROGRAM Auxiliary sources of water supply  Reservoirs  Cisterns  Swimming pools  Canals  Rivers Learning Objective 3 Components of Water Supply Program

PRIVATE FIRE PROTECTION SYSTEMS Designed to protect individual occupancies from fire Private homes, businesses, manufacturing plants, or public buildings Main purpose is to alert occupants Some systems alert and extinguish Learning Objective 4 Fire Detection Systems and Their Components

DETECTION SERVICES Smoke detector Ionization chamber detector Flame or light detector Visible smoke detector Cont. Learning Objective 4 Fire Detection Systems and Their Components

DETECTION SERVICES Rate of rise detector Fixed temperature detector Carbon monoxide (CO) detector Manual pull alarm Water flow switch or excess flow alarm Learning Objective 4 Fire Detection Systems and Their Components

MONITORED ALARMS Combination of alarms Must be monitored at some level Transmits to fire department Sometimes plagued with frequent false alarms Learning Objective 4 Fire Detection Systems and Their Components

SPRINKLER SYSTEMS Residential sprinklers Commercial and industrial Wet pipe system Dry pipe system Deluge system Cont. Learning Objective 5 Extinguishing Systems and Their Components

SPRINKLER SYSTEMS Preaction sprinkler system Sprinkler heads Standpipe systems Foam systems Carbon dioxide Cont. Learning Objective 5 Extinguishing Systems and Their Components

SPRINKLER SYSTEMS Dry chemical systems Wet chemical extinguishing systems (Class K) Fire extinguishers Obsolete agents Fire pumps Pressure-reducing devices Learning Objective 5 Extinguishing Systems and Their Components

WATER Most common fire extinguishing agent in use today Extinguished through cooling and smothering Highest specific heat of any known substance Latent heat of vaporization Numerous delivery systems available Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

FOAM PROPERTIES Its effectiveness over plain water is becoming popular Properties of extinguishing fires Components are water and foam concentrate Traditional purpose is to extinguish flammable liquids Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

CLASS B FOAM Forms a layer above the surface of the liquid Chemical foams Mechanical foams Protein foam Fluoroprotein foam Cont. Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

CLASS B FOAM Alcohol-type protein foams Aqueous film-forming foam (AFFF)  Most popular type of synthetic foam High-expansion foams  Will reduce visibility to nearly zero Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

CLASS A FOAM Much lower concentration than class B Can stick to vertical surfaces Can pre-treat areas in advance Blocking gel Wetting agents Fire retardant Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

CARBON DIOXIDE Extinguishes by smothering Installed where water is not the agent of choice HALOGENATED AGENTS Break the chemical chain reaction Concern about their effect on the ozone layer Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

CLEAN AGENTS Do not deplete the Earth’s ozone layer DRY CHEMICAL Mixture of finely divided powders DRY POWDER Used on combustible metals (Class D) Learning Objectives 6 and 7 Different Types of Extinguishing Agents How Various Extinguishing Agents Work

Summary The fire department should have a close working relationship with the local water company A thorough knowledge of the strengths and weaknesses of the water system is necessary for decision-making purposes at the fire scene Firefighting agents are all applied through some type of system Pre-plan what is necessary to support these systems in case of fire