Why ozone mistakenly given bad name


To begin with, the major elements of smog are large quantities of man-made hydrocarbons or VOCs (volatile organic compounds ?C pollutants), nitrogen oxides (nitric oxide and nitrogen dioxide), ozone, oxygen, and single oxygen molecules.

Man-made hydrocarbons are created from various sources of pollution, such as vehicle emissions and industrial processes (such as smokestacks). If you take these man-made hydrocarbons out of the "smog" equation, then you simply have a natural process where the ozone and nitrogen dioxide are normalized to safe and healthy levels (according to Health Canada, a Canadian federal health dept.). However, when you add a large amount of man-made hydrocarbons to the equation, then the amounts of nitrogen dioxide and ozone are artificially increased.

Click here for more scientfic detail about how smog is made.


Unfortunately, man-made hydrocarbons are very complicated and difficult to measure. In which case, ozone has commonly been used as a yardstick for the severity or presence of smog since it is easy to measure. This despite the fact that in smog, it occurs in much less concentration than the hydrocarbons, or even the nitrogen dioxides (the grayish-brown color is a result of the high level of nitrogen dioxide).

Conveniently, placing the emphasis on ozone takes some of the pressure off of large manufacturers, who are releasing millions of pounds of toxins into the air every year, and the government agencies that also stand take heat for allowing this to happen.


Ozone actually plays a part in breaking down hydrocarbons, though. Ozone is proven to help remove the impurities in the air, due to its power as an oxidant (second most powerful known), meaning it burns and destroys particulate with which it comes in contact. Ozone comes into contact with a large number of contaminants since it is highly reactive.

However, in the process of breaking down man-made hydrocarbons in particular, the result is the production of elements that combine to produce additional ozone and nitrogen dioxide, above and beyond what is produced naturally. Even though hydrocarbons are quickly being broken down, there is always a large amount of hydrocarbons in the air at once when smog is present, due to the sheer volume of these pollutants being produced. In such cases where there is an extremely high amount of hydrocarbons in the air, nature simply cannot keep up without overcompensating.

You also have to consider that by itself, ozone is a natural purification agent used in a variety of ways for this purpose (by nature and man, see last paragraph of article for examples). It is not at all unhealthy at reasonable levels, and it is highly rare for ozone to raise to excessive levels under natural or normal circumstances. On the other hand, man-made hydrocarbons are completely unhealthy under any circumstance. Even common sense will tell you that the black, sooty smoke coming from a tail pipe or smokestack can only be harmful to your health.

If there is just a moderate or reasonable amount of hydrocarbons (natural as well as man-made) in the air, the ozone helps to break them down without reaching unnaturally high concentrations. This is why smog is primarily a big-city problem, since mass amounts of emissions are generally emitted in the air of large metropolitans. Rarely do less-populated areas experience smog and ozone problems, even though ozone is naturally produced in similar quantities in big and small cities alike. Case in point, children raised on farms are 40% less likely to develop asthma than those in urban areas.


Also, this is why ozone air purifiers are safe. Most indoor environments have virtually no ozone to begin with, due to the air-tight way most homes and buildings are constructed. This is unfortunate since ozone is an effective, natural air purification agent.

Plus, although indoor air pollution is much more of a health problem than outdoor air pollution (according to the EPA), your home or workplace will not have anywhere near the man-made hydrocarbon concentration that is found outdoors during smog conditions, which is the reason the ozone level becomes artificially high. Even if you have many other pollutants inside, no other contaminant will cause ozone levels to raise above desired levels (in the reaction process) quite like man-made VOCs (made from industrial processes, vehicle emissions, gasoline). The scientific community is still not sure exactly why it happens, only that it does.

All things considered, you can see the folly of pointing the finger at ozone as the culprit of our pollution problems. Especially when you consider that ozone is natural, and that it is used as a purifying agent for a variety of applications. Some of its uses include water treatment and purification, food preservation, cancer and HIV treatment, and odor removal.

However, you should take precaution to ensure that the ozone level does not rise too high. Most ozone air purifiers are designed to produce an ozone concentration of about .04 ppm (parts per million) when operated according to instructions, which is within all standards (including OSHA and the FDA). Fortunately, ozone is a self-policing element, since it's odor becomes obnoxious to most well before it becomes a health hazard, as opposed to the refreshing and purified smell it gives off when occuring at safe and healthy levels.

In addition, IPS LifeTech air purifiers utilize a unique technology that does not rely on inexpensive sensors to ensure that the ozone level remains safe (Guaranteed Safe Ozone Levels).

IPS ozone and negative ion air purifiers

Ozone in the "ground level" under normal conditions

Under normal conditions, the stratoshere (where the ozone layer resides) drops moderate amounts of ozone (O3) into the troposphere (ground level). Ozone is originally made from the combination of the suns ultraviolet rays and oxygen.

The ozone molecules then react with naturally occuring nitric oxide molecules (NO) to form nitrogen dioxide (NO2).

Nitrogen dioxides then absorbs sunlight, which causes it to "photo-dissociate" (separate) into single oxygen atoms (O) and nitric oxide atoms (NO).

The oxygen atoms (O) then combine with oxygen (O2) to make ozone (O3).

The ozone molecules then either combine with nitric oxide atoms to begin the process all over again, or react (ozone is highly reactive) with other particles in the air (generally particles that are harmful when inhaled). Ozone reacts with other particles by breaking off into one O2 molecule, and one O1 molecule. The O1 molecule attaches to the other particle, causing it to oxidize (ozone is the 2nd most powerful oxidant known). When ozone reacts with other particles, it oxidizes (burns/destroys) them. In which case, ozone helps to control airborne pollutants and allergens, while leaving behind breathable oxygen.

According to the Health Canada Federal Department, ozone normalizes to safe levels
(under normal conditions, such as that described above).

Ozone levels when large amounts of man-made hydrocarbons (VOCs) are added to the air

Man-made hydrocarbons (VOCs, or Volatile Organic Compounds) are created from industrial processes and vehicle emissions (among many others).

Hydrocarbons combine with nitrogen dioxide (NO2), which (in a very complex reaction not fullu understood by the scientific community) break down into O1 atoms and additional NO2 molecules.

An increased amount of NO2 results in a grayish-brown haze (smog). It is known that NO2 is this color, which is manifested when it occurs in high concentrations.

An artificially increased amount of O1 and NO2 also equals an increased amount of O3 (ozone) produced. As explained in the process described above, O1 combines with O2 to make O3, and NO2 "photo-dissociates" to create O1, which of course results in O3.

In addition, the increased amount of NO2 combines with the large amounts of hydrocarbons to make even more O1 and NO2, perpetuating the vicious cycle of high NO2 and O3 concentrations. In this unnatural process, the NO2 will actually be much higher in concentration than the O3, which is evident by the fact that smog is the same color as NO2 (grayish-brown as opposed to the blue color of ozone).

Since it is the easiest to measure, ozone is used as a barometer for the severity of the smog. However, hydrocarbons from smokestacks and tail pipes are much more harmful than the ozone itself, even at higher concentrations.

Even though the hydrocarbons are quickly broken down when they enter the air (with the help of ozone), there is still a large amount of man-made hydrocarbons in the air at any given moment under smog conditions, since hydrocarbons are being produced in such large quantities. This is why (as an example) asthmatics have a hard time breathing outdoors when smog is present.