A Day In The Life Of The Underhill-Jericho Fire Department A Mathematical Day That Is As Told by Dwight DeCoster

Who is the Underhill-Jericho Fire Department (UJFD) You Ask? We are an almost all volunteer fire dept. –We have 1 Paid full-time member We are made up of 46 active members –3 Chiefs and Assistants –5 Line Officers, Captains and Lieutenants –25 Firefighters –4 Fire Police –4 Auxiliary Members –Various Fire Specialists The UJFD was organized in 1913 We have had ten Chiefs in that time They each served an average of 9.4 years The UJFD has had 10 VT Fire Officers or Firefighters of the Year We have business owners, soldiers, teachers and lots of other folks on staff

What Is It That The UJFD Does? We run a wide variety of calls averaging 200 calls per year

Our Most Prevalent Type of Call is the Automobile Accident The UJFD averages over 50 automobile crashes per year. –A team of five firefighters can have the doors and roof removed from an average car in less than 4 minutes using hydraulic tools –A Hurst Hydraulic cutting tool operates at pressures between 5 and 10 thousand PSI!!! –The UJFD has spreaders that are capable of spreading even the toughest metals over 36 inches!!

The UJFD Takes On One of Our 20 average Fires!! How does the UJFD get there? –First we must be dispatched via the 911 reporting system on our dispatch frequency of megahertz –It takes an average of four minutes for the volunteers to respond to their respective station and get a truck on the road. –The firefighters respond on one of nine different pieces of apparatus, each apparatus with a different and distinct ability –The UJFD territory is so large that it can take 20 minutes to get to a house driving ten miles over the speed limit!!

How Do We Find The House We Are Looking For? Smoke Signals –No!! Just kidding well sort of! Enhanced 911 Emergency Call –Gives the FD a locatable address (Street Name and Number –Underhill and Jericho 1 mile equals numbers miles equals numbers miles equals numbers Some other local towns use thousands or ten thousands to equal a mile

What Happens Once We Get There? One of three Chiefs is the first on the scene usually. –He must determine many things but the most important is, is there anyone in the home. –Second most important is he must begin to determine the method of fire attack and how much water will that take. This calculation is called the Fire Flow Rate. Volume (cubic Feet)/100= Gallons per minute required

Fire Flow Rate Depends On Volume Of The Structure Do We Have This? Or This? ft 3 /100 = 125 gallons per minute 1200 ft 3 /100 = 12 gallons per minute A Very Big Difference Right??

So Where Does The Water Come From? Manmade –Hydrants –Pools –Water System Fill Site –Tanker (9Tanker2) Natural –Rivers –Ponds –Lakes The Chief must first do his Fire Flow Calculation and then do another calculation of the volume of the nearest water source to see if it is adequate. Length x width x depth x 7.5 gallons = volume of water source

How Does The Water Get From the Source To The Fire? The Fire Department uses a piece of apparatus called an engine or a pumper A pumper’s job is to take water from a source and supply it to various size hoses and nozzles at a specific pressure measured in psi This water is then applied to a fire where it turns to steam thus removing the heat from the fire

Miscellaneous Fire Appliance Facts Sizes of Hose and Max Output 1” = 100 GPM 1 3/4” = 150 GPM 2 1/2” = 200 GPM 6” = 400 GPM Water vs. Steam –One gallon of water will expands to 1603 times its own volume when heated to 212 degrees Fahrenheit for 223 cubic feet of steam –Steam can occupy more space and absorb heat in a quicker manner

Does Friction Play A Role In Delivering Water To A Fire? It most certainly does but in a negative way Friction is the act of something rubbing against another thing thus losing energy In this case it is the water rubbing against the inside of the fire hose. Bernouli’s principle of incompressible flow explains Friction loss Of course a fire engineer cannot perform this function easily on the fire scene so there are handheld calculators that help them. The engineer must calculate friction loss in order to provide the right amount of water to maintain the necessary Fire Flow

Let’s Put Some Wet Stuff On The Fire!! The fire nozzle is the main tool of the interior firefighter. They come in many shapes (1 1/2, 2 1/2, master stream) and types (Straight bore or Variable Gallonage) Variable Gallonage is the most common and popular as it allows the firefighter on the end of the attack line to determine how much water they need to put out the fire

An Interior Firefighters Best Friend The Self Contained Breathing Apparatus (SCBA) Positive Pressure Facepiece supplied by a pressurized source of breathing air. –30 minute air bottle (manufacturers specs) depends entirely on size and fitness level of firefighter average firefighter gets between 10 and 20 minutes –Air supply bottle is pressurized to 3200 psi

How Do Firefighters See Where They Are Going In The Smoke? Thermal imaging is the answer!! This instrument can read variations in temperature to 1 degree! This great piece of technology helps firefighters: –see victims through the smoke –see dangerous situations that could get them in trouble –see heat building and prepare them for flashover Temp readable ranges from 100F to 1000F –The picture in the backdrop shows heating ducts in the fire house reading 125 degrees

So We Put Out The Fire Now What Else Do We Do? Carbon Monoxide calls continue to be a huge part of our call volume. –In past years they have averaged 10% of our calls –We utilize Scott Test equipment to do testing. Normal air contains about 20.9 % oxygen by volume Average CO levels are around 4 ppm Negative health effects can begin around 50ppm with prolonged exposure

So We Put Out The Fire Now What Else Do We Do? Part II Natural Gas and Propane Leaks are also about 10% of our call volume. –Our Scott Test equipment is capable of detecting methane as well as oxygen. Normal air contains no detectable amounts of methane The Lower Explosive Limit (LEL) of Natural Gas is 5% with an Upper Explosive Limit (UEL) of Natural Gas 15% The Lower Explosive Limit (LEL) of Propane is 2.5% with an Upper Explosive Limit (UEL) of Natural Gas 9.7%

What Does It Cost To Run The UJFD? Annual Budget is approximately $325,000 –Included in this are all budget items Replacement trucks Day to day running of department Firefighter safety gear and new equipment Capital Plan (see next slide) Repayment of loan for building new station

What Does The Future Look Like For The UJFD?

UJFD Mathematical Roundup A local fire department is a great place to teach math. There is everything from primary numeracy to advanced algorithms friction and volume Three different types of calculations can be worked on for air, water and hydraulics Money, time, temperature, distance, area and volume, etc. are also present I had no idea I used math so much fighting fire!!