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These articles were created for your reading pleasure, and so that you can discover the various aspects of the air filter. We also have articles on heating and air conditioning systems.

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  • Tips For Buying An Air Filter Online

    Tips For Buying An Air Filter Online

    To promote good health, it is important to consider the use of a quality air filter as filters help to clear the polluted indoor air. Shopping for an air filter can be a very confusing experience due to the wide variety of options, sizes and prices available in the market. If done online, the shopping experience may become further complicated. Here are some tips that you should always bear in mind when shopping online for an air filter:

    air filter articles Check the reliability of the online seller

    In today's digitized world, it is very simple to set up an online store. Therefore, it is very important to be fully aware about the market reputation of the seller to protect yourself from any scam or fraud. Although it is convenient to shop for an air filter from the comfort of your bedroom, it is always advisable to check the online seller's physical address and phone number. This will prove to be of immense help in case you have queries or problems related to the purchased air filter. You should be aware of the seller's market reputation. Oxyclean Air Filters has an excellent reputation, since 1995. To see some testimonials, go here.

    2. Compare products on different sites

    When making an online purchase, it is important to fully know about the features of a product. When buying an air filter, you should browse products by different manufacturers to gain better product knowledge. You should compare the products in terms of area coverage, MERV ratings, resistance to air flow, and strength of the frame. By comparing products online, you will be able to make a sound purchase decision and get the best value for your hard earned money.

    3. Get the best deal

    The prices of air filters differ on the basis of their area coverage and other features. Some of the most affordable, standard air filters are suitable for use only in small spaces. Some other air filters come with additional features such as bells and an indicator light, which lets you know when an air filter is due for change. When comparing product features, you should also consider product prices so that you may get the best deal. When comparing prices, you should also factor in transportation and shipping costs to get a more accurate view of the total costs. Oxyclean Air Filters offers bundle deals and discount packages. In addition, Oxyclean will beat any competitor's price.

    4. Closely read terms of the deal

    When shopping online, do not rush through the purchase. You should closely read the terms and conditions associated with the air filter sale. Some air filters come with a warranty coverage of several years. In case a warranty is applicable, you should know what parts are covered under the offer and in what conditions will the warranty be considered void. When buying an air filter online, you should also confirm the delivery dates and review the seller's refund policy.

    5. Keep records of the online purchase

    Online shopping on reliable sites can be a pleasant experience. However, you should ensure that you do not give out extra financial information. When you buy the air filter, you should keep all records of your online transaction and any emails that you receive from the online seller. Once you receive your credit card statement, read it closely and check for any unfamiliar or hidden charges.

  • How a Good Air Filter Can Help Clean The Air You Breathe

    How a Good Air Filter Can Help Clean The Air You Breathe

    An air filter Keeps dust under control

    You can be allergic to dust and not even realize it. You just notice your breathing is hindered, you catch your breath often, find taking deep breaths difficult and you are more tired. You feel "things" crawling on your skin.

    Dust allergies are common indoor breathing enemies. Other symptoms of dust allergies include nausea, vomiting, rashes, skin irritations and headaches.

    air filter article An air filtration system with a high quality air filter can remove dust mites from the air and prevent them from recirculating.

    * Turning the blower of your forced-air cooling/heating system on for 15 minutes after cleaning will help remove dust from the air, also.

    * If you cannot afford an in-home filtration system, purchase a room-size air cleaner, complete with a good air filter, and put it in your most affected room. You may also do this in addition to your whole house system.

    An air filter keeps pet dander under control

    Many believe a house is not a home without our furry family members. As much as you may love your furry friend, you may be allergic to the pet dander. Or, your guests may have allergies. Pet dander is another common household pollutant that negatively affects breathing for those with heightened sensitivity.

    * You and your guests will breathe easier by purchasing an air cleaning device, complete with an air filter that fits your budget. Place several small air purifiers throughout your home.

    * Place another one in each bedroom and run it periodically throughout the day and all during the night. Remember that to be effective, portable cleaners need to be used in a confined area.

    An air filter will clean the air of exhaust fumes

    Exhaust fumes pollute the air by clogging it with impurities. Some homes have connecting garages that allow fumes to seep under the adjoining doors. This allows fumes to enter your home. Having a good air filtration system with a clean air filter, removes any exhaust fumes that impinge on your home's interior. Of course, an air filter will not protect you if you forget to turn off your car. Leaving your car running in the garage can be deadly. To protect from this you need a carbon monoxide detector.

    * Have an automatic air cleaner/exhaust fan wired to your garage door. Set it so every time your garage door opens or closes, the fan turns on.

    Exhaust fumes also come from cooking, baking, using kitchen appliances and other kitchen-related activities. A good air filter in your overhead exhaust fan, located directly above your stove, will remove exhaust fumes. This reduces your risks of breathing impure air for long periods of time, making breathing easier.

    An air filter will reduce other indoor air pollutants

    There are many pollutants that can negatively affect your breathing. This is why indoor air pollution is such a serious issue. In addition to pet dander and living dust mites, these pollutants include dry cleaning fumes, smoke, mold spores and viruses, etc.

    Indoor pollutants of all kinds play havoc on breathing, especially if a person has heightened sensitivities. Using a good air filter, whether portable or built-in, will help remove offending particles from the air.

    * Remember to clean your air ducts regularly. Dirty ducts are breeding grounds for all kinds of indoor pollutants that negatively affect breathing.

    You can have the most efficient, budget-friendly and recommended air cleaners in the world, but If you do not change the device's air filter regularly, it will not matter. A dirty air filter is like having no air cleaner at all. Change the air filter regularly and improve your indoor air quality. Watch your breathing improve.

  • All About The Carbon Air Filter

    All About The Carbon Air Filter

    A carbon air filter is an affordable, highly effective way to keep the air in your home clean. Most air purifiers use activated carbon to filter impurities from the air. Carbon air filters are also available for furnaces and air handlers. The carbon inside the air filter is actually a charcoal product that's been specially treated to open up its surface pores and make it more absorbent. Contaminants pulled from the air are then trapped into the air filter and neutralized.

    There's a long list of impurities and contaminants that a carbon air filter can remove from the air, including:

    * Dust

    * Pollen

    * Certain types of gases

    * Chemicals

    * Allergens

    air filter articlePet dander

    * Pollutants

    A carbon air filter can also help in a home where odors are an issue. In homes where there are smokers, pets, or poor cooks, prone to occasional mishaps, a carbon air filter can neutralize those odors and help keep a home smelling clean.

    What are the Benefits of Using a Carbon Air Filter?

    Does someone in your home struggle with allergies, asthma, or a similar condition? If so, a carbon air filter can help by removing dust, pollen, and other allergens from the air.

    Carbon Air filters can also absorb airborne chemicals, like the ones found in household cleaners. This is great for those who have chemical sensitivities.

    Even those who don't suffer from any specific condition will benefit from a carbon air filter because clean air can help you to feel healthier and more energetic.

    Also, those with dogs or cats know what it's like when pet smells are pretty strong and company comes over. It can be pretty embarrassing when there are strong odors in the air. Fortunately, a carbon air filter can help remove those embarrassing odors. Your visitors might not even realize you have a dog or a cat in your home.

    Choosing a Carbon Air Filter

    The type of air filter you choose will depend on your specific needs. Some filters are particulary suggested for those dealing with an odor problem. Others are suggested for households where one or more family members suffer from allergies. There are also air filters designed to purify the air throughout a home. There are also portable, "spot filters," which are smaller air filters designed to filter the air in just a single room.

    When choosing a carbon air filter, check its MERV ratings. Filters are graded on a scale of 1 to 16. The higher the rating, the more efficient a filter is at removing certain particles and pollutants from the air. The filters found in most homes have a MERV rating of between 1 and 4. But, those who want something more powerful should choose a filter with a MERV rating of 8 or higher. Due to the impregnated carbon in a filter, the carbon air filter will have a MERV rating no higher than 8.

    No matter which type of carbon air filter you choose, you need to know when it has to be replaced. Eventually, the filter will have trapped so many contaminants that it won't be able to hold anymore and will lose its effectiveness. Typically, a carbon air filter will need to be replaced every one to three months. However, some air filters can last longer.

  • Tips For Choosing The Best Air Filter For Your Home or Office

    Tips For Choosing The Best Air Filter For Your Home or Office

    Air filters are a great way to get rid of dust particles and pollutants from your indoor environment. There are essentially two types of air filters, called arrestors and non-arrestors. Mechanical air filters or arrestors accumulate trapped particles but require maintenance. Non-arrestor air filters generate an electrical charge and may change the chemical composition of particles. The choice of the best air filter for your home or office will depend largely on your need. Here are a few factors to consider when buying an air filter:

    air filter article Area Coverage.

    When buying an air filter, it is important to ensure that its square footage coverage equals or is greater than that of the room where it will be placed. This will ensure that the air filter effectively removes dust and irritant particles from the area.

    2. Research the market well.

    When buying an air filter for your home or office, you should research the market well and understand the different types of HVAC air filters. Some of the most commonly available air filters include woven fiberglass, washable aluminum mesh, electro-statically charged and pleated types. These air filters differ from each other in terms of filtering efficiency. Many homeowners buy the cheaper, woven fiberglass filters, which should be replaced on a monthly basis. However, woven fiberglass is outdated and not very effective at cleaning dust particles and other allergens from the air.

    3. Check out the MERV of an air filter.

    When buying an air filter, you should check out its MERV (Minimum Efficiency Reporting Value). The MERV is an industry benchmark that tests the air filters in line with the ASHRAE Standard 52.1-1992. The MERV categorizes filters through 1 to 20 in terms of their efficiency in cleaning the air. Air filters such as woven fiberglass, electrostatic and washable have a rating of MERV 1 to 4. You could do much better for just a little more cash. Pleated filters provide greater media square footage and they usually have a MERV of 6 to 13. This allows the air filter to capture more micro-particles and pollutants. For offices and buildings, you may consider buying HEPA (High Efficiency Particulate Air Filter) and ULPA (Ultra Low Penetration Air Filter) Air Purifiers, which have a rating between MERV 16 and 20. Therefore, a higher MERV rating indicates better ability of a filter to clean the air.

    4. Purchase air filters which can remove all type of allergens.

    Dust particles and allergens in the air can cause several types of allergies. As a result, you may experience allergy attacks on a frequent basis. It is advisable to remove the source of the allergens in your home, in addition to filtering the allergens from the air.

    5. Purchase air filters which can be embedded in a ventilation system.

    High efficiency air filters can be installed in your central air conditioning system, or into the ventilation system of your house or office. By placing an air filter into the air conditioning or ventilation system, you will be able to create a centralized "Air Purifier" that cleans air inside your home or office. This will prove to be a convenient option instead of shifting the air purifier system from one room to the other.

  • What Type of Air Filter Is Best for Your Air Conditioning Unit?

    What Type of Air Filter Is Best for Your Air Conditioning Unit?

    There are many different types of air filters and air conditioning cleaning systems used to not only filter the air in your home, but also protect the often costly heating or cooling equipment used to protect and maintain your unit. In this article we will cover some of the different types of air filters, and cleaning systems available to consumers.

    Before we get into the details about air filters and air cleaning systems, it's important to understand why having a high efficiency air filter is so important. You might be, or might not be surprised, to find out that the air inside your home or apartment is far more contaminated and polluted than the air you and your family breathe outdoors. We are talking about the air you and your family breathe on a daily bases, most of the time.

    The indoor air that you and your family breathe can be contaminated with micro-particles such as dust, smoke, and lint. In many homes, pet dander, mold, and bacteria, complicate the problem even more. In fact, 99% of the particles circulating in your home or apartment air are one micron and smaller which is less than 1/40th the diameter of a human hair. These micro particles can aggravate your allergies, and irritate your respiratory system or simply make your home or apartment dusty and dirty.

    The most common air filter that you would find at a hardware store tends to be very basic only capturing very large particles, therefore not protecting you from the more dangerous contaminants floating through the air and eventually your lungs.

    The first step to moving toward cleaning the indoor air in your home is to pay attention to the MERV rating of the air filter in your unit. A national organization, ASHRAE, developed the standard for testing air filters. With this test, the results are expressed in MERV (minimum efficiency reporting value). Simply stated, the higher the MERV rating, the more efficient the air filter will be in removing contaminants and pollutants from the airflow.

    It is always best to try and find an air filter that fits your unit with the highest MERV rating available. If you would like to take it one step further, you can have a system added to your unit that uses HEPA technology, however this solution is often very expensive, and the replacement filters are also very costly. While HEPA filtration is very effective it is often times not necessary. Always be sure to choose an air filter with the highest MERV rating available.

  • All About Air Filter MERV Ratings

    All About Air Filter MERV Ratings

    The Minimum Efficiency Reporting Value (MERV) represents the filtering efficiency of an air filter as set by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). The metric is evaluated using the ANSI/ASHRAE Standard 52.2 Test Procedure, which counts airborne particles both upstream and downstream of the air filter. The standard clearly outlines the testing protocol that needs to be followed to ensure reliable and consistent test results of air filter performance.

    The MERV is calculated using a series of tests to determine efficiency of the air filter.

    The test involves injection of particles in twelve different sizes into an air stream that passes through the air filter. By counting the airborne particles of each particle size, the efficiency of air filter is determined. The test is repeated six times for each particle size and the lowest values are then used to calculate the Composite Minimum Efficiency Curve for that air filter. The twelve size ranges are then distributed into three larger groups, namely E-1, E-2 and E-3. An average of the Composite Minimum Efficiency for each group is used to find out the average Particle Size Efficiency (PSE) of the air filter. Finally, the percentages are used to calculate the MERV rating of an air filter.The MERV is an industry standard that allows comparison of filters made by different manufacturers.

    The MERV is a standard rating system that helps to compare the efficiency of an air filter made by different manufacturers.

    The MERV has a numerical value ranging from one to twenty. The higher the MERV rating, the greater the filter's efficiency in capturing and holding out dust particles of smaller specified size ranges. Air filter with an MERV 1 through 4 will be most effective in removing large, dust particles. These flat or panel air filters are commonly used in residential furnaces and air-conditioners. Such air filters are generally used to protect equipment and in light industrial and residential projects. As they have low efficiency, they are not used directly to maintain indoor air quality. Air filters with MERV rating of 5 through 13 are great at removing finer dust particles. These pleaded or extended surface air filters have medium efficiency and are fairly efficient at removing small to large airborne particles. Although they are almost as effective as HEPA filters, they are much less expensive and can filter out most airborne indoor particles. Due to less airflow resistance, these air filters have a quieter HVAC fan operation and higher airflow rates than HEPA filters.

    Air filters with higher efficiency are often mistaken for HEPA filters. Air filters with higher MERV rating of 14 to 16 are often misidentified as HEPA filters. They are widely applied to remove contaminants and particles that may harm human health and productivity. They are commonly installed in hospital inpatient and general surgery areas, and some of the best commercial buildings. An Air filter with MERV rating of 17 through 20 is used in clean rooms and pharmaceutical manufacturing premises. In these areas, maintaining the highest standards of cleanliness and removing airborne dust particles is of utmost importance so that product quality may not get affected.

  • Tips For Choosing a Good Car Cabin Air Filter

    Tips For Choosing a Good Car Cabin Air Filter

    Know what you're buying

    A car cabin air filter is a filtration device that is attached to the air intake of your car's ventilation system. It works to improve the quality of the air inside the car, and to get rid of pollution from the outside air that enters the car. Many air filters are made using a pleated paper system, but there is a whole host of other filtration media.

    A blend of cotton and paper is common material used for these air filters. Other models use miniature paper filters not unlike those found in the air filter of the car's engine intake system. Other models include shaped cotton cartridges.

    Don't get confused

    Often the car cabin air filter is confused with the internal combustion air filter. The latter is the one under the hood of the car that stops dust from getting into the car's engine inner workings. If this air filter is damaged, it may damage the car's performance. The distinction between these two different filters is very important.

    When buying a car cabin air filter, look for a high quality air filter that will improve the air that you and your passengers breathe. There are certain green air filters available on the markets that are more sustainable. These are perhaps the best air filters to buy if you are worried about allergens.

    Other tips

    When changing your air filter try to stay away from parking under trees. Pollen may enter the system and damage it. If you are an allergy sufferer you should think about changing your cabin air filter more often than people who do not have allergies. Also, you should look for an air filter that is particularly thorough in its filtration. Remember that when you turn on the AC or the heater in your car, this is when air filter does its work.

    When installing an air filter remember that condensation will collect on it, creating a fertile breeding ground for mold. Eventually, a musty smell may become apparent due to the moisture and particles clogging up the filtration device. For this reason, it is a good idea to change the cabin air filter at least once a year. These air filters are not expensive, so it will save you a lot of trouble if you buy in advance.

    To summarize, remember that your air filter is distinct from the internal combustion air filter, and that it should be changed at least every year. The best air filters are the greenest ones because they will save you money and will improve the quality of the air inside your car as well.

  • Tips For Choosing a Good Car Engine Air Filter

    Tips For Choosing a Good Car Engine Air Filter

    A good car engine air filter can save you money on gas, help your car operate at optimum performance levels and help you avoid repair bills in the long run. Choose the best one by following the tips below.

    1) Do your research into what size air filter your car uses. Do not laugh over this one. Some misinformed car owners can think any air filter will fit into their car. You are different though. You realize that the correct one fits like a glove.

    * Use your auto owner's manual to find the correct size air filter for your car. If you do not have a manual, go online and do research into your car model, type and year.

    * Or, go to your local auto supply, dealership or parts shop. Some larger department stores have auto departments that will also help in this area. They usually have manuals that list air filter sizes for a variety of cars. If you have any questions about using these manuals, employees can help you.

    2) Know your budget. Air filters come in a variety of prices, ranging from dirt cheap to expensive. Many quality and reputable manufacturers offer air filters at low prices to suit a wide variety of budgets.

    3) Know your car's make, model and year. What air filter your car needs will be based on these factors. Learn this information and save yourself the embarrassment of appearing as a uninformed car owner. Protect yourself by knowing this information.

    4) Know your purpose. Do you plan on using your air filter in a high performance car? If so, adjust your purchase accordingly. For instance, an air filter manufactured with a high performance car in mind will be totally under-utilized in a small commuter car.

    5) Buy a well-known brand. Well-known brands have a reputation for manufacturing high quality products that stand the test of time. Purchasing a lesser known brand may save you money, but be made of lower quality materials that allow debris to enter your carburetor. This can be the beginning of a huge repair bill down the road.

    6) Perform an on-site matching process. Make sure the air filter you purchase is the same as your current one. You can easily do this by removing your current air filter while in the store's parking lot.

    *Take the filter into the store and match it against the replacement one. If it matches perfectly, in size and shape, you have the correct fit. Doing this on-site matching will save you the time and expense of making a return trip to the store.

    7) Understand that an air filter can be made from different materials. All serve the purpose of improving air flow and providing proper filtration to your engine. One of the most common is a pleated-paper filter that makes it easy to replace for only a few bucks.

    An air filter plays a crucial role in optimizing your car's performance. It keeps your carburetor and engine clean by removing impurities. By doing this, it improves air flow to your engine and improves horsepower.

  • How Do I Measure My Air Filter, Or Furnace Air Filter ?

    How Do I Measure My Air Filter, Or Furnace Air Filter ?

    Most air filters have their dimensions stated in their nominal state which simply means the actual dimensions of the filter are rounded up or down. Below is an example of the nominal dimensions, and the actual size of the air filter compared to each other. Why air filter manufacturers began this practice is beyond me. What I do know is that this practice has made buying an air filter very confusing for some folks.

    Take the popular 16x25x5. Without even thinking about it I can come up with three 16x25x5 filters that are all different in their actual sizes depending on the brand of the air filter. As a matter of fact, as I write this, a good customer that has been ordering from us for several years just emailed us that this time he ordered the wrong size filter. Below is his situation:

    Always ordered:........Honeywell.... 16X25X5 Real Size 15 7/8 x 24 3/4 x 4 3/8

    This Time Ordered:....BDP Brand:... 16X25X5 Real Size 15 3/8 x 25 1/2 x 5 1/4
    No way the filter he ordered this time will fit his Honeywell filter housing.

    The take-away of this story is that you should be very careful when ordering an air filter because the dimensions you see on the filter frame or filter housing are almost never the true dimensions of the filter. These items are very expensive to ship back and forth, not to mention the inconvenience to you. So, double check, double check. Don't assume that if you see a 16x25 by whatever on our site, that this is the filter to order. You need the model number, or the "ACTUAL" dimensions.

    I refer to
    the 16x25x5 air filter in this article, but these discrepancies in sizes apply to any filter, including 20x20 - 20x25, etc. The table below shows two 16x25x1 that have different actual dimensions. There are more.

    See below for more ideas.

    Filter A Filter B
    Nominal Dimensions 16 x 25 x 1" 16 x 25 x 1"
    Actual Dimensions 15½ x 24½ x ¾" 15¾ x 24¾ x 7/8"

    air filter sizes


    Method 1: If you are currently using a throw-away fiberglass air filter, take the

    size written on your existing air filter and deduct 1/4 inch from both sides. For

    example, if your throw away filter is: 20 X 20, then you would order

    19 3/4 X 19 3/4 actual dimension.


    Method 2: Actually measure your existing air filter, but be sure that your existing

    filter fits well.


    Method 3: Measure the opening provided for the air filter in your furnace, ceiling

    filter grill, or wall filter grill and deduct 1/4 inch from both sides. For example, if

    the opening provided for the filter in your furnace measures 18 X 20, then you

    would order 17 3/4 X 19 3/4


    Method 4: Look up the model number of the filter housing, or the part number of

    the existing filter


  • The Benefits of an After-Market Air Filter Explained

    The Benefits of an After-Market Air Filter Explained

    This article will discuss why in many cases it is better to buy an after-market air filter instead of the brand name air filter. I will compare the cost and quality of the after-market air filter with the brand name air filter.

    First, lets look at the quality of the air filters. Many people believe that the after-market air filter is of inferior quality to the brand name air filter. The truth is that this is rarely the case. By using shrewd marketing, the brand name air filter companies have created a perception in the general public that the brand name air filter is a better filter than the after-market air filter. You do not fall for these marketing techniques because you read articles like this one, but many other consumers do not.

    A manufacturer of after-market air filters basically has two ways to compete with the brand name air filter company. If he wishes to succeed, the after-market manufacturer must make an air filter that is better than the brand name filter. Two ways to do this is to make an air filter that is more efficient than the brand name air filter in removing pollutants and contaminants, and by using better materials.

    This difference in the efficiency of the after-market air filter and the brand name air filter can be compared by referring to the MERV rating of the air filters in question. By doing this, most often you will find that the after-market air filters offer higher MERV rated air filters than the brand name filters. After-market air filter manufacturers are forever trying to make a more efficient filter than the brand name filters.

    The other way for an after-market air filter manufacturer to compete is by keeping price as low as possible. The after-market manufacturers cut costs by not printing a whole bunch of marketing words on the filter frame. Usually, they print the size, and that’s it.

    Another way after-market air filter manufacturers cut cost is by not marketing or advertising. There are big savings there that are passed on to the consumer.

    You may be interested in knowing that brand name filters are often made by the same air filter companies that make the after-market air filters. The brand name companies spend a great deal of their money building the brand name. In many cases the brand name is all they own. They have air filter manufacturers make the filters, and then they sell them through air conditioning contractors and distributors.

    My last thought for you is, be “Filter Smart” and consider the after-market air filter when ordering your air filters. Once you stick your filter in the filter housing, it matters not what color the filter is, or what words are written on the filter frame. The only thing that really matters is how efficient the filter is in removing pollutants and contaminants, and whether or not the filter will hold up to the pressures exerted on it by the airflow.

  • Air Filters In Hospital Critical Care Areas

    Air Filters In Hospital Critical Care Areas

    Hospitals have a variety of air filter needs depending on the purpose of any one area or room. Areas of special concern are critical care areas where various pollutants and contaminants must be controlled or eliminated as much as possible from the airflow. These areas include the areas where surgery is performed, where babies are delivered and care for, where patients recover, etc. It is critical that pollutants and contaminants be removed for the well-being and health of patients.

    In these critical care areas, air filters should be located on both sides of the air conditioning equipment, in other words, upstream and downstream of the air conditioning equipment. The air filters upstream of the equipment must have an average efficiency of 30% or better. On the other hand, the air filters downstream of the supply blower must have an efficiency of 90% or better. One type of air filter recommended for this purpose is a high efficiency synthetic and glass micro fiber rigid extended surface air filter.

    Some of the pollutants and contaminants to be filtered are; Bacteria, Fungi, Pollen, and of course dust. Along with those already mentioned, there are many more pollutants and contaminants that must be removed from the airflow in order to have a safe, healthy environment for patients.

    Once high efficiency air filters are in place, they must be inspected on a regular basis. A visual inspection should be made to make sure that the filtering media is not torn, and the integrity of the air filter frame is intact. This evaluation should be performed with the blower running, as well as with the blower idle.

    To keep the filtration at optimum efficiency, the air filters must be replaced and/or cleaned periodically, as per manufacturer specifications. Records should be maintained of inspections, replacements, pressure drop, and the types of air filters installed.

    Finally, depending on the use of the critical care area, it may be desirable to remove VOC’s (volatile organic compounds) from the area. VOC’s are gases that are released from certain liquids and solids found throughout hospital buildings, such as, building materials, plastics, solvents, etc. The list of solids and liquids that emit VOC’s is nearly limitless.

    A HEPA (high efficiency particulate arresting) air filter will not remove VOC’s. For this job, a high capacity gas phase absorber air filter is needed. These are air filters that incorporate charcoal and/or potassium permanganate as the filtering media. These air filters are very effective in absorbing hundreds, if not thousands of gases. When the air filter becomes saturated, it is removed and replaced with a new air filter.

    See table below:


    Some contaminants listed in the table use specific chemical compounds, some represent classes of components, and others are mixtures of variable composition. Activated charcoal's capacity for odors varies somewhat with the concentration of air, humidity, temperature, and with the actual velocity used through the filters. The numbers given represent typical or average conditions and might vary in specific instances. The values in the table have been assembled from many sources including laboratory tests and field experience. In cases where numerical values were not available, the author has listed his opinion of the probable capacity based on general experience. This table should be used as a general rule only. The capacity index has the following meaning:

    4. High capacity for all materials in this category. One pound takes up about 20% to 50% of it's own weight-average about 1/3 (33 1/3%). This category includes most of the odor causing substances.
    3. Satisfactory capacity for all items in this category. These constitute good applications but the capacity is not as high as for category four. Absorbs about 10% to 25% of it's weight-average about 16.7%.
    2. Includes substances which are not highly absorbed but which might be taken up sufficiently to give good service under the particular conditions of operation. These require individual checking.
    Absorption capacity is low for these materials. Activated charcoal cannot be satisfactorily used to remove them under ordinary circumstances.

    Acetaldehyde 2
    Acetic Acid 4
    Acetic Anhydride 4
    Acetone 4
    * Acetylene 1
    * Acrolein 3
    Acrylic Acid 4
    Acrylonitrile 4
    Adhesives 4
    Air-wick 4
    Alcoholic Beverages 4
    * Alines 2
    * Amonia 2
    Amyl acetate 4
    Amyl alcohol 4
    Amyl ether 4
    Animal odors 3
    Anesthetics 3
    Aniline 4
    Antiseptics 4
    Asphalt fumes 4
    Automobile exhaust 3
    Bathroom smells 4
    Benzene 4
    * Bleaching solutions 3
    Body odors 4
    Borane 3
    Bromine 4
    Burned flesh 4
    Burned food 4
    Burning fats 4
    Butadiene 3
    Butane 2
    Butanone 4
    Butyl acetate 4
    Butyl alcohol 4
    Butyl cellosole 4