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SMOKE DETECTORS An photoelectric detector is a light sensor. When used as a smoke detector it includes a light source (infra-red LED), a lens to collimate the light into a beam, and a photodiode or other photoelectric sensor at right-angles to the beam as a light detector. In the absence of smoke, the light passes in front of the detector in a straight line. When smoke enters the optical chamber into the path of the light beam, some light is scattered by the smoke particles, and some of the scattered light is detected by the sensor. An increased input of light into the sensor sets off the alarm. Another type of photoelectric detector works by using a straight line infra-red beam from the sender to the receiver. When smoke enters the beam, some light is scattered which results in less light detected by the receiver. A decreased input of light into the receiver sets off the alarm. Photoelectric smoke detectors are quick in detecting slow burning, smoky fires. They are less sensitive to false alarming from cooking and bathroom steam than ionization smoke alarms. This type of detector is cheaper than the optical detector, however it is sometimes rejected for environmentalreasons. It can detect particles of smoke that are too small tobe visible. It includes a tiny mass of radioactive americium-241, which is a source of alpha radiation. The radiation passes through an ionization chamber, which is an air-filled space between two electrodes, and permits a small, constant current to flow between the electrodes. Any smoke that enters the chamber absorbs the alpha particles, which reduces the ionization and interrupts this flow of current, setting off the alarm. Approximately 0.2 micrograms of Am-241 is used, which has a half life of 432.2 years. This means that it does not have to be replaced very often, and also makes it safer for people at home (as it is less radioactive). Alpha radiation (as opposed to beta and gamma) is used for two further reasons: alpha particles have high ionization (so sufficient air particles will be ionized for the current to flow), and they have low penetrative power - meaning they will be stopped by the plastic of the smoke detector and/or the air, reducing the risk of harm to people.

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FIRE ESCAPE PLAN Home Fire Escape Plan Family members must know what to do in the event of a fire in their home. Unless a small fire can be easily controlled, it is recommended that fighting the fire be left to professional firefighters and that family members escape safely from the home. A home escape plan must be created and practiced so that each person knows exactly what to do. It also is important to practice Exit Drills In The Home. Most residential fires occur between 8 p.m. and 8 a.m. Deaths from residential fires occur in greater numbers between midnight and 4 a.m. when most people are asleep. An average of 800 fires strike residential buildings each day in the United States. More than 6,500 persons die each year from fire - more than half of them children and senior citizens. The majority of these deaths are in home fires. Regardless of the cause of the fire, a home may be filled with smoke. This is a very dangerous situation. Family members may be unable to see very well. The smoke and toxic gases may cause dizziness and disorientation. In the confusion, one can easily become lost or trapped in the home. Family members must understand that their safety depends upon quickly leaving the home. It has been proven that exit drills reduce chance of panic and injury in fires and that trained and informed people have a much better chance to survive fires in their home. Plan Ahead The first step in escaping a fire in the home is to plan ahead. Installing smoke detectors in the home and being sure they are in good working order can alert family members alerted to the presence of smoke or fire before it is too late. Together, family members can decide on an escape plan in the event of a fire in the home. Bedroom doors should be closed while people are sleeping. It takes fire 10 to 15 minutes to burn through a wooden door. That's 10 to 15 minutes more for the inhabitant to escape. Next, family members should visit each bedroom and figure out two escape routes - The normal exit The other exit through a door or a window Plan an Escape Route Each member of the family should know how to get safely outside by at least two routes. Family members should practice opening their windows to become familiar with their operation. Jammed windows should be identified and repaired. If, during a fire, a window is jammed, it may be broken out with an object and a blanket or towel placed over the frame to cover shards of glass. However, it is much safer to open a window than it is to break the glass out. Never put locks or bars on windows or doors that cannot be opened from the inside. Realize the Danger of Smoke Each member of the family should understand the importance of crawling low under smoke. Smoke and heat rise so the best place to find fresher, cooler air is near the floor. When a person is caught in a building filled with smoke, they should drop on hands and knees and crawl to the nearest exit. Test all closed doors before opening them. Feel the back of the door. If it is hot, don't open it. Turn and go to the second route of exit. If the door is not hot, open slowly but be prepared to slam it closed if there are flames. Practice what to do if you become trapped. Since doors hold back smoke and firefighters are adept at rescue, the chances of survival are excellent. Close doors between you and the smoke. Stuff the cracks and cover vents to keep smoke out. If there is a phone, call in your exact location to the fire department even if they are on the scene. Wait at the window and signal with a sheet, flashlight or something visible. Establish a Safe Meeting Place A special meeting place should be established a safe distance from the house. It could be a mailbox, the neighbor's driveway or a large tree in the yard. Whatever it is, it must be something that is stationary and won't be moved (such as a car). This is where everyone meets in the event of a fire. It also prevents family members from wandering around the neighborhood looking for one another, or worse, being tempted to re-enter the burning house for one thought to be trapped inside. Once outside at the special meeting place, a person can be sent to the neighbor's to call 911. If anyone is missing, give that information to the fire department immediately and tell them where the probable location of the missing person could be. Under no circumstances should anyone re-enter the burning building. Practice Your Fire Escape Plan One very good step in the planning of a home fire escape plan is to make a floor diagram of the house. Mark the regular and emergency escape routes, as well as windows, doors, stairs, and halls. A good way to practice the effectiveness of a home fire escape plan is to position each family member in his or her bed, turn all the lights off, and activate the smoke detector by depressing the test switch. Each family member should help "awaken" the others by yelling the alert. Family members should exit their rooms according to the plan, crawl low under smoke, practice feeling doors for heat, and meet in the designated location outside the home. Not all "homes" are single residential structures but include apartments and other types of buildings. Some additional discussion may be helpful in the home escape plan. Most high-rise or multi-story apartment complexes post fire escape plans for all residents to see and follow. However, these plans seldom include escape routes for each apartment. Family members must develop and practice an evacuation plan for their individual apartment. Exit Safely From a Structure Jumping from upper floors of a building should be avoided. However, it is possible to hang from a second story window and drop feet first to the ground without significant injury. A sprained ankle or broken leg is better than dying. Parents can purchase fire ladders for the bedrooms, or instruct children to use an adjacent porch or garage roof to await rescue by the fire department. When exiting such a structure, do not use the elevator. Elevators are notorious for stopping at the fire floor and killing the people inside. A power failure may cause them to stop in between floors. Use the fire escape or an enclosed fire resistive stairwell to exit. As a family, explore the building so that every exit is familiar, including those from storage, laundry and recreation rooms. If the hallways become smoke-filled as the result of a fire, memory can help in finding the exits. Look for these important features in the building - enclosed exit stairways, clearly marked exits, clean hallways and lobbies, automatic sprinklers, fire alarm systems and smoke detectors. Remember, Plan Ahead! Remember, the first step toward escaping a fire is to plan ahead. Practice a home fire escape plan throughout the year and be sure that if anything should change around the home, it is included in the home fire escape plan.

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FIRE EXTINGUISHERS Fire extinguishers are divided into four categories, based on different types of fires. Each fire extinguisher also has a numerical rating that serves as a guide for the amount of fire the extinguisher can handle. The higher the number, the more fire-fighting power. The following is a quick guide to help choose the right type of extinguisher. Class A extinguishers are for ordinary combustible materials such as paper, wood, cardboard, and most plastics. The numerical rating on these types of extinguishers indicates the amount of water it holds and the amount of fire it can extinguish. Class B fires involve flammable or combustible liquids such as gasoline, kerosene, grease and oil. The numerical rating for class B extinguishers indicates the approximate number of square feet of fire it can extinguish. Class C fires involve electrical equipment, such as appliances, wiring, circuit breakers and outlets. Never use water to extinguish class C fires - the risk of electrical shock is far too great! Class C extinguishers do not have a numerical rating. The C classification means the extinguishing agent is non-conductive. Class D fire extinguishers are commonly found in a chemical laboratory. They are for fires that involve combustible metals, such as magnesium, titanium, potassium and sodium. These types of extinguishers also have no numerical rating, nor are they given a multi-purpose rating - they are designed for class D fires only. P A S S Pull the Pin at the top of the extinguisher. The pin releases a locking mechanism and will allow you to discharge the extinguisher. Aim at the base of the fire, not the flames. This is important - in order to put out the fire, you must extinguish the fuel. Squeeze the lever slowly. This will release the extinguishing agent in the extinguisher. If the handle is released, the discharge will stop. Sweep from side to side. Using a sweeping motion, move the fire extinguisher back and forth until the fire is completely out. Operate the extinguisher from a safe distance, several feet away, and then move towards the fire once it starts to diminish. Be sure to read the instructions on your fire extinguisher - different fire extinguishers recommend operating them from different distances. Remember: Aim at the base of the fire, not at the flames!!!!

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