There is a deafening absence of perspective here....It might be nice to hear about the science behind the regulation before we condemn it.
Content Warning: Now's the time to click off somewhere if you're easily bored by details. This is probably more than you'd every want to know about the impact of bottom paint VOCs on Mother Earth.
OK...a bit on the "science". (In truth, it's not really science...more like information).
The most harmful effects of VOCs concern indoor air quality, which is why you see all the warning labels on paint cans and the like about only using the product with "adequate ventilation". I don't think anyone has a problem with regulating indoor VOCs as it's clearly a hazard. In fact, I know a guy who died from liver failure after an overdose of VOCs on a home improvement project -- paint stripper, I think it was.
Seems the gears of governmental progress have now shifted to outdoor air quality, and, again, I have no problem with cleaning that up either. As Jim Pendoley mentioned in his post the good folks at EPA have done yeoman's work over the last 25-30 years fixing the air quality in the US. Most of the visible polution in the US is gone and what we have left is mostly what's known as "photochemical smog" --- the brown haze you see over a few large metro areas during the day when the air is still. When it occurs, it is almost always in and around very large cities. Most of the cities effected are in the developing world and, of course, California. You can google "photochemical smog" and see how truly ugly the stuff is.
So it's because of photochemical smog that the EPA gets involved.
From the EPA website:
Respirable Particles | Indoor Air | US Environmental Protection Agency
In the United States, emissions of VOCs to the outdoors are regulated by EPA mostly to prevent the formation of ozone, a constituent of photochemical smog. Many VOCs form ground-level ozone by “reacting” with sources of oxygen molecules such as nitrogen oxides (NOx), and carbon monoxide (CO) in the atmosphere in the presence of sunlight.
While I suppose ground-level ozone is one issue, apparently VOC's also contribute to photochemical smog because they react with nitrous oxides (NO and NO2) in the formation of something called peroxyacetyl nitrates (PAN). If you go to Photochemical Smog
you can read all about it.
To save you some time, here's the meat of it:
Certain conditions are required for the formation of photochemical smog. These conditions include:
1. A source of nitrogen oxides and volatile organic compounds. High concentrations of these two substances are associated with industrialization and transportation. Industrialization and transportation create these pollutants through fossil fuel combustion.
2. The time of day is a very important factor in the amount of photochemical smog present. The following...illustrates the daily variation in the key chemical players...
- Early morning traffic increases the emissions of both nitrogen oxides and VOCs as people drive to work.
- Later in the morning, traffic dies down and the nitrogen oxides and volatile organic compounds begin to be react forming nitrogen dioxide, increasing its concentration.
- As the sunlight becomes more intense later in the day, nitrogen dioxide is broken down and its by-products form increasing concentrations of ozone.
- At the same time, some of the nitrogen dioxide can react with the volatile organic compounds to produce toxic chemicals such as PAN.
- As the sun goes down, the production of ozone is halted. The ozone that remains in the atmosphere is then consumed by several different reactions.
3. Several meteorological factors can influence the formation of photochemical smog. These conditions include:
- Precipitation can alleviate photochemical smog as the pollutants are washed out of the atmosphere with the rainfall.
- Winds can blow photochemical smog away replacing it with fresh air. However, problems may arise in distant areas that receive the pollution.
- Temperature inversions can enhance the severity of a photochemical smog episode. Normally, during the day the air near the surface is heated and as it warms it rises, carrying the pollutants with it to higher elevations. However, if a temperature inversion develops pollutants can be trapped near the Earth's surface. Temperature inversions cause the reduction of atmospheric mixing and therefore reduce the vertical dispersion of pollutants. Inversions can last from a few days to several weeks.
4. Topography is another important factor influencing how severe a smog event can become. Communities situated in valleys are more susceptible to photochemical smog because hills and mountains surrounding them tend to reduce the air flow, allowing for pollutant concentrations to rise. In addition, valleys are sensitive to photochemical smog because relatively strong temperature inversions can frequently develop in these areas.
If you read far enough in the above link you'll discover another interesting tidbit, specifically:
To begin the chemical process of photochemical smog development the following conditions must occur:
- The production of oxides of nitrogen (NOx).
- The production of volatile organic compounds (VOCs).
- Temperatures greater than 18 degrees Celsius.
OK.....let's stipulate that all of the above is correct and that our bottom paint is a big, bad culprit in all this photochemical smog business. How about the following -- we agree to let the EPA regulate boat yard VOCs:
- When the sun is shining, and
- When the air temp is above 18C (approx 65 F), and
- When the wind velocity is below 12 knots, and
- When it's not raining, and
- When the boat yard is in a valley and subject to temperature inversions, and
- It's in the hours immediately preceeding and during morning rush hour.
Other times we should be free to varnish and paint away to our hearts content. Right?
You see, that's my problem....in stead of regulating something according to when and how the "science" says the problem is being created, government always seems to take the easy way out and just prohibit it's use an anywhere and at all times.
How's that for a little "perspective"?