Some devices that are advertised as air purifiers purposely emit large amounts of ozone, the main component of smog. CARB recommends that ozone generators not be used, except for approved industrial purposes where harmful exposure to ozone is prevented. Not only are ozone generators ineffective at cleaning indoor air, but inhaling ozone poses serious health risks for humans and animals. This fact sheet discusses these health risks and provides effective, alternative solutions to address indoor air quality problems.
Indoor "air purifiers" or air cleaners that intentionally emit ozone are often called “ozone generators." Manufacturers sometimes inappropriately refer to ozone as “activated oxygen,” “super oxygenated” or “energized oxygen,” which implies that ozone is a healthy kind of oxygen. Because ozone reacts with some other molecules, manufacturers claim that the ozone produced by these devices can purify the air and remove airborne particles, chemicals, mold, viruses, bacteria, and odors. However, ozone is only partially effective at cleaning the air when it is used at extremely high, unsafe levels that pose a serious health risk.
Air cleaners that utilize ionizers and electrostatic precipitators are other types of devices that emit ozone, but do so as a by-product of their design and function. These devices are designed to electrically charge particles in the air and cause them to attach to surfaces in the room, such as walls or floors. Ozone is released through the charging process, although these devices typically emit much less ozone than ozone generators.
Some devices are marketed with advertising claims that they will kill viruses, bacteria, mold and other biological contaminants, and remove chemical contaminants and odors. However, when ozone concentrations are below the health standards, it does not effectively remove biological contaminants. Ozone also does not remove particles (e.g. dust and pollen) from the air, including the particles responsible for most allergies. Ozone generated by air purifiers does little to remove chemical pollutants. In fact, ozone has been found to react with existing chemicals in the air to create additional toxic pollutants, most notably formaldehyde and ultrafine particles. Some consumers purchase air purifiers to eradicate odors. There is scientific evidence that ozone concentrations below the health standards are not effective in removing many odor-causing chemicals. Ozone is also known to deaden one’s sense of smell. Not only does this disguise rather than eliminate odors, it can also have the dangerous effect of decreasing a person’s ability to detect high ozone levels. Unlike the situation in air, ozone can be used successfully to purify water in some applications. This is because high levels of ozone can be used in the water, most of the ozone reacts in the water, and people typically are not present when the ozone is used.
Ozone generators can produce indoor ozone levels several times higher than the State's outdoor 1-hr and 8-hr health standards of 90 parts per billion (ppb) and 70 ppb respectively. Many commercial ozone generators emit more than 5,000 mg of ozone per hour of operation, which could result in unhealthy levels of ozone in indoor air.
People who buy ozone generators may not be aware that ozone can harm the cells in the lungs and respiratory airways. Exposure to ozone irritates and inflames the lining of the respiratory system. This causes symptoms including coughing, chest tightness, shortness of breath, and impaired breathing. Ozone can worsen asthma symptoms, and may contribute to the development of asthma. Elevated exposures to ozone can cause permanent lung damage, and repeated exposure can even increase the risk of dying among persons already in poor health. Persons especially vulnerable to health problems from breathing ozone include children and those who already suffer from asthma or other respiratory diseases, including the elderly. There are many experimental studies on animals, including dogs, cats, hamsters and guinea pigs, that show respiratory effects from exposure to ozone. Birds are especially sensitive to the effects of air pollutants, including ozone.
The unfortunate answer is that misleading advertising by manufacturers is very effective, and no government agency has the authority to fully regulate these devices. Thus, CARB is actively working to educate professionals and the public about the dangers of using ozone generators.
CARB strongly advises against the use of ozone generators in spaces occupied by people or animals. Other governmental agencies agree with this advice. CARB provides a list of potentially hazardous ozone generators sold as "air purifiers", which is periodically updated. If an ozone generator is not on this list, it does not mean that it is safe for use.
Prior to purchasing an air cleaner, consumers are encouraged to eliminate or reduce indoor pollution sources and to ventilate areas with outdoor air. The most effective method of controlling indoor air pollution is through prevention: eliminating pollution at its source. To minimize the release of pollutants indoors:
Use plenty of ventilation: be sure there is adequate airflow to/from the outdoors. This can be achieved by opening windows, using exhaust fans near pollutant sources (e.g. above stoves while cooking), and increasing airflow through the use of mechanical ventilation systems. If your home is equipped with a central forced air system, you should also consider upgrading the filter to at least MERV 13.
In 2007, CARB adopted a regulation to limit ozone emissions from indoor air cleaning devices. Over 300 manufacturers have submitted test results and obtained CARB certification of their air cleaning devices as required under our regulation. Certification is based on a device's low (usually near-zero) ozone emissions and electrical safety. The following information provides the list of CARB certified air cleaning devices and additional information on how to choose a safe and effective air cleaner.
5 Common Pitfalls When Buying The Best Air Purifier
There are many industry measurements in air purification that gauge performance such as CFM (Cubic Feet Per Minute). This metric provides a view into the efficiency related to the air purifier, by measuring how many cubic feet per minute this air purifier can scrub. Another measure that is vital to improving your indoor air quality is called dwell time
We breathe in and out, day and night, about 12 to 20 times or more per minute. You may take even more breaths, depending on your activity level. That means you take 17,000 to 30,000 breaths per day! You need air to provide your body with oxygen, and your respiratory system helps to get rid of toxins in the body. Breathing is as essential to life as the heart is to pump blood through your veins. But what happens if the air around you is polluted? If you don’t like the taste of something you are eating, you can choose to stop eating it.
Unfortunately, even if you know the air around you is contaminated or bad for you, you won’t be able to simply stop breathing. You can choose is to surround yourself with the best air possible. One way of eliminating toxic pollutants in the air is to run an indoor air purifier in your bedroom or in the areas where you spend most of your time.
When you look up air purifiers online, you will find many different options, from low-cost models in your neighbourhood retail store to high-end contraptions that come with a hefty bill. Just with anything you want to buy, make sure you do your research and don’t buy the wrong unit.
A good air purifier needs to be able to address the widest range of indoor air pollutants in your surroundings. It needs to have the right filters to target the pollutants that affect you most. Before we get into the five air purifiers you should never buy, let me take a few moments to talk about the dangers of breathing polluted air:
In some industries, it’s a well-known fact that workers are exposed to toxic chemicals and fumes. Think about hair stylists in salons, welders, health care workers, and more. Even if you spend most of your time at home, the air that you breathe is contaminated to some degree.
EPA studies show that poor IAQ may be more dangerous than outdoor pollution. In many cases, the indoor air quality is two to five times worse than outdoor air, in some cases, even up to 100 times worse.
Remember the term “Sick Building Syndrome?” One of the problems is that indoor air pollutants come from many different sources. There are well-known pollutants such as pollen, dust and dust mites, tobacco smoke and wood smoke. Toxic pollutants can also emanate from the very materials and furniture that surrounds you. There is formaldehyde in particleboards, toxic fumes coming off paint, stains and other finishes, fabrics that have been treated… the list is very long.
You may also contribute to indoor air pollution inadvertently if you use many personal care products, apply harsh cleaning products, cook on a gas stove or get a lot of dry-cleaning done, for example. In modern construction buildings, these indoor air pollutants are often allowed to build up because the homes have been made so energy efficient and less leaky.
Indoor air pollution can affect people quite differently. Some are very sensitive to odors and chemicals. Others develop allergies to dust and other particles. Some do not seem to be affected at all for a long time. The people that are most at risk are babies and children because they are so low to the ground and they take more breaths than adults. The elderly also need to be careful.
The EPA warns that IAQ-related health effects can appear immediately in the form of allergic-like responses or much later in the form of chronic diseases or even cancer. That is why it is so important to assess the air we are breathing and to take steps to breathe cleaner air, if possible.
Here are some tips for you to consider when you look for the right air purifier. Air purifiers are not regulated by the government, and there are so many designs, filters and systems to choose from.
The air purifier that would be best for you depends on your surroundings, sensitivities and concerns.
1) Never buy an air purifier from a manufacturer that promises the strongest motor
The first air purifier to avoid is one that boasts a super strong motor. This seems illogical. After all, isn’t stronger better?
Not in this case.
When air is pushed through an air purifier at a high rate, the filters won’t be able to remove as many toxins, meaning you may be exposed to them longer.
If your air purifier uses a HEPA filter, a strong motor may actually prove damaging over time, as it will fray the strands making up the filter. That, too, will decrease the air purifier’s efficiency.
If your air purifier uses granular activated carbon for the removal of odors and chemicals, great. It is one of the most important filters out there.
But these filters also work best when the air is allowed to pass through at a slower rate. That way, the carbon can adsorb the highest amount of VOCs and toxic chemicals.
2) Never buy an air purifier that has a medical-grade HEPA filter ONLY
The second air purifier that you should never buy is one that comes with only one filter - even if it is a good one.
The pleated HEPA filter has been shown to remove 99.9 percent of particles that are 0.3 microns in size, which is great. These filters are important to people who are sensitive to dust, pollen and other particles.
But particles are all these HEPA filters are catching.
Chemicals and odors will pass right through, and they can affect your health and well-being in the long term.
According to the Canadian government, longer-term health effects of chemical exposure might include organ damage, weakening of the immune system, reproductive problems and birth defects, effects on the mental cognitive or physical development of children as well as cancer.
http://healthycanadians.gc.ca/healthy-living-vie-saine/environment-environnement/chemicals-chimiques-eng.php
The EPA also acknowledges that breathing polluted air can lead to short-term and long-term health effects.
Immediate effects are often similar to colds and may include sneezing, irritated eyes, throat and nose, difficulty breathing and more.
Breathing polluted air over a long period of time has been linked to serious and often fatal conditions, including respiratory diseases, heart disease, and cancer.
http://www.epa.gov/iaq/ia-intro.html
In order to remove airborne chemicals and gases, an air purifier needs more than just a HEPA filter.
A complete air purifier must include a deep-bed activated carbon filter that is packed with many pounds of carbon. Carbon is also used in water filters, gas masks and medical treatments to counteract poison.
It is the most effective filter media on the market to trap airborne chemicals, gases and odors. It can remove formaldehyde, traffic fumes, benzene, smoke as well as hundreds of other volatile organic compounds.
3) Never buy an air purifier that has less than a 2.5-inch deep bed of carbon
The third air purifier you should never buy is one that doesn’t have enough carbon.
As I mentioned earlier, activated carbon is the most important filter to get rid of chemicals and odors in the ambient air.
But just because a manufacturer states that the unit features an activated carbon filter, that does not mean it comes with enough carbon or that it comes with the right type of carbon.
Some manufacturers spray a thin layer of activated carbon over mesh and call that an activated carbon filter. Technically, they are right, but it won’t be effective for long.
Others offer a thin wall or box of activated carbon that also limits its efficiency and longevity.
An effective and long-lasting carbon filter features a deep bed of granular activated carbon and offers at least 2.5 inches of progressive diagonal filtration to maximize its filtration capacity.
This all makes sense once you understand how activated carbon works.
Activated carbon is made from organic materials such as charcoal, wood and coconut shell, heated up in the absence of air and crushed into granules.
It is then treated with oxygen, which opens millions of tiny pores between the carbon atoms and produces a large surface area for gases and odors to get adsorbed.
Adsorption means that pollutants attach themselves to the surface area of the carbon by way of chemical reaction.
Activated carbon has been proven good or effective in the adsorption of more than 200 chemicals and odors, including ozone, octane, formaldehyde, benzene, acetone, diesel fumes, nitroglycerine, organic chemicals, turpentine, toluene, sulfuric acid and smog.
One pound of activated carbon contains a surface area of approximately 100 acres.
Once it becomes saturated, activated carbon needs to be replaced. So, of course, the more carbon there is, the longer and more effective the air purifier will be.
4) Never buy an air purifier from a manufacturer that offers fewer than 100 different models or options
The fourth air purifier you should avoid is one that is too generic. If a company only makes a few models, then that is what they will try to sell you.
But chances are, these air purifiers won’t address your needs perfectly. You need choices. You need a proper particle filter, a sizable carbon filter, the right kind of unit and the bells and whistles that provide cleaner air for you.
A person living in a hot and humid, flooding-prone area needs a very different air purifier than a person living in a city apartment with pets.
If you are uncertain about which air purifier, filters or options work best for you, call the company. They will ask the right questions to narrow down your choices and to meet your needs.
AllerAir, for example, offers more than 500 different units, but that doesn’t have to scare you off. The units are divided into series to make selection easier and there are guides you can consult. Still, calling the AllerAir team to discuss your options may still be your best bet.
For the right kind of air purifier, you should consider the size of the area, the type and severity of indoor air pollution, your preference in terms of free-standing or HVAC-attached air purifiers, your sensitivities (if applicable), budget and design.
5) Never Buy an Air Purifier that is Not Proven
What Should You Buy?
The fifth air purifier you should never buy is one that hasn’t been proven to work. Ask the manufacturer or dealer for proof, read reviews, get informed. This should be just part of your normal research. An air purifier is an investment and it should last a long time, so you want to choose one that can produce results, won’t be too noisy, features a look you can live with and that doesn’t need replacement filters all the time.Proof means lab tests that were done to show a unit’s efficiency. In AllerAir’s case, for example, the AirMedic Pro 5 series was shown to remove toxic chemicals formaldehyde and benzene by more than 90 percent within 6 hours. On the low setting.Choosing the right air purifier is an important decision, and there is no one-size-fits-all solution. The more choice you have, the better.It also a good idea to look for a company that backs its units with an iron-clad guarantee and a good warranty.Arm yourself with information and talk to the companies to figure out which way to go.Good luck, and breathe easy.