Saturday 23 April 2011

The Return Of The Smog

There is smog again in London and said to be bad. One report suggests that this might increase the number of deaths by 700 or so. There will be no figures available for those affected to one degree or another whose damage may be permanent. This one is another problem that has been coming for some time but off the agenda of any recent government.

Last year in an item I did about a visit to London I commented that the air quality was as bad as anything I had experienced when young. For anyone growing up in industrial towns in the early to mid parts of the 20th Century smog was a regular hazard. In some places, notably like Sheffield, the air was literally filthy.

The one that does feature in the history books is the Great Smog of London in the first week or so in December 1952. Although traffic levels were not as high as at present the dependence on coal burning for almost all domestic and industrial activity as well as a great deal railway movement put a huge amount of stuff into the air which polluted everything.

It was in the last week of December 1952 that I was in London for a handful of days over the New Year. Although the smog had dispersed by then the place still stank and was filthy. Moreover, many still seemed to be shocked by it.

There are figures given for the recorded deaths but these are disputed because there may have been many suffering serious complaints who were just finished off and recorded under those. Again those left damaged were uncounted. It is my view that over the next two to three decades it is likely that this left its effect on the expectation of life figures.

Today, London does not have anything like the industry it did then and there are no steam trains other than the very occasional heritage ones a few days a year. Also, Clean Air Acts, cheap oil and gas of the last quarter of the 20th Century means that the coal smoke has gone.

So what is replacing it? When it comes to measuring Air Quality finding out about it is a question. Typically, it is possible to discover exactly what Queensland in Oz is up to but to work out what the Met Office does, that trading arm of the Ministry of Defence, involves a tortuous journey through an official web site that leaves you little wiser than when you started.

Essentially, the quality measuring is looking at Nitrogen Dioxide, Sulphur Dioxide, Ozone and Particulate Matters of certain sizes, largely reflecting dust and pollen for the larger and fuel combustion for the smaller. From this a scale is given telling us how bad it is, but in urban areas it is rarely good.

There are now some things missing from the equations. Over the last decade or two there has been extensive use of air conditioning systems in buildings all pumping out bad air and heat from inside to outside. Also, the requirements for kitchens etc. in the hugely increased number of eating places means extensive venting in the streets and air generally.

Within these buildings it is typical now for many products to be in use where recent fine particle technology has been applied and these are present in quantity, often in the air conditioning systems. These particulates will be very much smaller than the minimum levels presently tested for and substantially derived from petro-chemicals with other potentially toxic chemicals in addition.

So while the fuel pollution levels of the past are measured these are not. But what we do not know is how far this fine particle technology is now applied in the production of fuel for vehicles to enhance performance and capability. The catalytic converters may deal with some particles but not these. So the fuel combustion measures may now be inadequate.

The air quality measures etc. in use were arrived at largely during the 1990’s and whilst under review have not had serious attention in relation to the new situation that has developed over the last decade. The situation is changing rapidly and the scientists in the UK have just not caught up with it.

But, what is important is the bottom line trading figures the Met’ Office produces for the Ministry of Defence.

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