Archive for January, 2010
How Fire Extinguishers Work
Fire has been around for a very long time now. It has benefited human kind in more ways than we can imagine. However, it has also destroyed homes and lives that are too precious for words. That’s why even if fires are necessary to us; it is still something to be afraid of. We need to be careful and take steps in order to prevent its rampage.
We never think of fire in a scientific way. We always say that’s what we use to cook food, to warm our body when it’s winter, etc. But fire is actually combustion, a reaction that happens when certain chemicals combine with oxygen to produce heat. Combustion needs three things, namely fuel, air, and heat. Fuels are something that burn, like wood, paper, and coal. By air, it is the oxygen around us. Heat can come from the surrounding temperature; stoves also produce heat.
To stop the fire from breaking out, we need to extinguish at least one of the three. That’s what fire extinguishers are for. They fight the fire using the substances inside. There are two substances in every can: one can be a solid, liquid, or gas material depending on which type you choose; the other is a propellant. The material is specially made for the sole purpose of fighting the fire. A propellant, meanwhile, helps push out the material because it is highly pressurized.
The four types of fire extinguishers: water, dry chemical, CO2, and metal/sand. Each of them has their own variations, and is used on different occasions. When buying a fire extinguisher, it is important to know what can cause the fire in that area. Is it simply caused by ordinary materials like paper or electrical equipment gone wrong?
Water extinguishers are, as the name says, water. This is the most common type and works by taking out the heat from the fire. It is never used in laboratories and electrical stores because it will worsen the fire. The cause of the fire should only be paper, wood, or other ordinary materials easily removed by water.
Dry chemical extinguishers are more versatile in its use. Because of the chemicals making up the extinguisher, it can also be used in electrical fires and those caused by flammable liquids. This is made up of foam or powder to separate the fuel from the air around it. Nitrogen acts as the propellant here, unlike water extinguishers which uses compressed air.
Carbon dioxide is a non-flammable gas which makes it a good choice for a fire extinguisher. The gas is kept at very high pressure inside the aerosol can to make it into a liquid substance. When released, the CO2 swells up and removes the fire. How? CO2 sucks up the oxygen in the fire and gets rid of the heat because of its cool temperament. The best way to use this fire extinguisher is in electrical things and flammable materials. It’s not the best choice for paper or wood-caused fire. Take note that this works really bad with metal fires as CO2 sometimes reacts with them in a different manner.
Lastly, metal/sand extinguishers. If the cause of the fire doesn’t work with any of the kinds above, then this is the solution. Flammable metals are the hardest to extinguish, so metal/sand extinguisher is the best choice for this.
Like I said earlier, be sure to know the cause of the fire because it would mean extinguishing the fire or making it worse. Putting water on electricity will electrocute you and others nearby. Instead of helping, you’ll harm them. When no other fire extinguishers are available, just run away from the fire and call for help. That’s the only thing you can do for now. Also, it’s impractical to put out a huge fire using only a fire extinguisher, since its power is limited. You might just harm yourself along the way.
Maintain the fire extinguisher in its good condition. Who knows when an emergency will happen? See if there are any leaks or damage to it. The pin should also be intact, because if not, maybe the pressure isn’t as high as it should be. It won’t work as well.
Fire extinguishers are made for us to use in case of emergency. That’s why there’s a glass to be broken first before you can take it out. Breaking the glass can alarm the fire department and cause panic to everyone. Fire is no laughing matter.
Becoming a Fire Fighter
Being a firefighter is something to be proud of. The job is rewarding, and it helps a lot of people. They give back to the community the blessing they have. Firefighters are the ones who stop raging fires and rescue those in danger. Not only that, they are also the ones who teach people about fire prevention. It’s no wonder why young children look up to them and want to like them.
However, the job of a firefighter is not that easy. They have the very important task of seeing to the welfare of others. That’s why there are a few requirements before a person can become a real firefighter.
First of all, they should be of legal age, which is 18. A high school diploma is also needed. These are general rules, but it actually depends on the fire department and state being applied on. While being extremely smart isn’t necessary to be successful in this field, being healthy and fit is a must. The process is a long one, and lots of examinations are needed to pass.
There is a medical check-up, written and psychological examination, an oral interview, and the hardest is the physical examination.
Before anything else, a check-up is required. This can be the easiest or hardest test you will meet along the way, depending on the condition you’re in. There is a drug test, which is no joke for the fire departments. Failing this, no matter how good you are, won’t mean anything to them. Also, having a clear eyesight and hearing is an advantage. But the test is thorough, so even the heart, lungs, and blood pressure will be checked.
Usually, the next exam would be the written one. It isn’t very hard, as long as you are prepared. This is similar to a college entrance exam; you have to study for it. The test is consisted of multiple choice problems. The topics are math, reasoning and spelling, among others. However, passing this doesn’t mean the rest is easy.
The truth is many applicants fail the psych exam. They just don’t have the mind and heart to do the work well. A good firefighter must have the personality to go with it. Sociable, calm, and decisive are only three of the qualities one must show. How can they act upon an emergency when they can’t make sense of the situation? And since firefighting requires teamwork, a person has to get along not only with his superior, but with his peers as well.
The oral interview is just similar to a job interview. They ask the applicants questions to get to know them better. Questions are usually put into scenarios and answering them to the best of abilities is needed. The interview can be a pass or fail one, no grading. This isn’t always the case, though. Also, other departments require an interview first before an applicant can proceed to the latter exams. So this is really very important.
Probably the hardest among the others is the physical agility exam. In order to pass this, one must have the lots of strength, stamina, and great agility. The work of a firefighter is really hard, and this test will show whether you’ll be able to handle the exhaustion that comes with it or not. Before taking this test, working out will be a big plus. Unless you’re very healthy and fit, this will drain you to the core. Don’t think that this isn’t necessary; because being a firefighter means that you will save lives. Just carrying one person requires heavy lifting, and that’s not including the heavy clothing being worn. Besides that, the smokes from the flames are pretty heavy on the lungs and you need to have a strong stamina to get through it.
The next time you see a firefighter passing by, respect him. He earned it. After going through the arduous process, those who passed really deserve it. Not only because of the examinations, but because they have the heart that comes with it. For someone to even think about being a firefighter, they would need to be committed. That’s a big part of the job, because they have to sacrifice a lot of things. They are even risking their lives saving and helping people. They teach the public about fires and how to deal with it. Children are right to admire this profession. It’s not only fulfilling, but also honorable.
