John Austin, editor of the UK Metric Association (UKMA) newsletter, looks at incorrect metric symbols used by the BBC.
The BBC has become something of a punchbag for members of UKMA over the years, here and in its newsletter. It’s perhaps not that the BBC is any worse than other institutions, such as newspapers, but rather that it is rightly considered an important voice in the country and those of us who like to see items properly described can be critical, but I think in a constructive manner.
The latest item that stimulated some angst in my mind was a description of atmospheric pollution levels during the Covid-19 lockdown period. The item described how pollution levels in Scotland had dropped significantly and were now below WHO recommended maxima. For the record I am quite well qualified to comment on this article as my scientific career was devoted to atmospheric chemistry (especially in relation to climate change) so I am quite familiar with the units used. The article can be found here https://www.bbc.co.uk/news/uk-scotland-55661358 However, the original no longer exists as it had undergone some changes following my comments. Nonetheless, the article to be found now still retains some of the criticisms that I had originally. This is, as many readers of Metric Views probably appreciate, frustrating. The SI is in itself a powerful system of units which comes with an imbedded philosophy which includes the correct symbolism. Use of different symbols is confusing and unnecessary. So when the BBC uses loose terminology it is impeding the high standard of communication inherent in the SI. When informed of errors in the use of symbols on the metric system, one expects the BBC to correct them, not carry on with their own editorial standards.
Here is the message I sent them.
“In previous correspondence with the BBC we have noted that the BBC tend only to use metric units in science articles, even though we would like to see that expanded. Nonetheless where exclusive use of metric exists, the proper abbreviations of units should be adopted as incorrect abbreviations cause confusion. The article in question was a science article and was full of incorrect abbreviations. The first point is that letter case is important regarding units. For example, 5 Mm would be 5000 km while 5 mm is well under a metre. The article in question has numerous uses of the abbreviation MCG. This is not an established scientific unit, and it is irresponsible to introduce it in the article as such. There is a case to be made for the use of mcg for microgram but in this day and age, the use of the Greek letter mu for micron (the official metric pre-multiplier) is available. This is correctly shown in the table on PM10 concentrations. So, you provide a mix of names for the same measurement. The next point is that what you label as MCG is actually a density mcg/m3. And there we come to the next point, not only is the Greek letter mu not available, but so too are superfixes and suffices. All of these characters, Greek letters, suffices and superfixes are available trivially in HTML in which the website is presumably written. For example, as well as the issues with units alluded to previously, we see NO2 in the article which should be NO<sub>2</sub> and that would then appear correctly on the webpage. For MCG you should use μg and for m3 you could use m<sup>3</sup> on the website coding. It really isn’t difficult and it looks like a subeditor task. Without proper use of symbols and measurements the webpages just look unprofessional.”
Whenever you send a message to a complaint service it nearly always comes back with a copy of the message sent. Ironically, and perhaps frustratingly, all the HTML symbols in the above text came back correctly (although they have not been corrected in the original text). In other words NO<sub>2</sub> in the article appeared as NO2 in the confirmation email and m<sup>3</sup> appeared as m3! Usually also, complaint services add that “all of our staff are exceptionally busy right now and will get back to you with an answer in due course”, or some such variant. And so it was with the BBC. But, we are in lock down, so what were the BBC staff doing, one wonders? As it happens I received a response in a short time which simply stated that the article had been changed following my remarks. However, perusal of my comments and the revised webpage can confirm that the correct chemical symbol for NO2 etc. are still not present. There has been some effort to address the BBC symbol MCG but only to persist with the less recommended version mcg/m3. On one occasion MCG is still present, but that is probably an editorial oversight.
I have checked for the use of the symbol mcg as an alternative to µ, see for example https://en.wikipedia.org/wiki/Microgram . It is not really recommended as it causes ambiguity with the term milli centi gram, which is also nonstandard and would be 10 μg. Apparently mcg tends to be used by the USA and the UK medical fraternity, although whenever I have seen drug concentrations these have always used the Greek letter. Indeed it is something of an insult to the Greeks to refuse to use their letters when presumably everyone else in Europe seems to be able to cope. Apparently the reason for the mcg symbol according to Wikipedia is that the US Federal Drug Administration thought that μ would be confused with m. Frankly I think you would need to be dyslexic to misread this symbol as another m. I know that when I was a young scientist and we had to send our research papers to be typed by the “typing pool” the symbol was always typed as u and we put the tail in by pen before distributing to other readers. Decades later, most of us have moved on. If the BBC is allergic to Greek, why don’t they use a u instead?
In the final analysis, this awful symbol mcg/m3 (which is properly and elegantly conveyed in the original scientific papers) could easily have been replaced by ng/L without all this pain and suffering, as the numbers would have been identical.