Blog

Opsis blog

RSS
Gas Concentration Units and Unit Conversions

Gas Concentration Units and Unit Conversions

On the most fundamental level, the signal from the sensor of a gas analyser gives the number of gas molecules, usually along an optical light beam or in a certain sampling volume. However, a concentration should not be expressed in number of molecules – the number would be far too big. Instead, it is scaled to a unit of weight-per-cubic-metre or volumetric share. How is the scaling done?
Read More »
Continuous Emissions Monitoring – What, Why, and How?

Continuous Emissions Monitoring – What, Why, and How?

Combustion-based heat and power production has historically been an environmental culprit. However, increased awareness and legislative requirements have improved the situation notably over the past decades. But which rules apply, which emissions-to-air limits are there, and how are the emissions determined?
Read More »
Instrument Interfaces

Instrument Interfaces

A lot of efforts are usually spent on gas concentration measurements and making sure that the measurements are correct. However, all that is of little value if the resulting data is not available. Here is where the instrument interfaces come in play.
Read More »
Spring is in the Air

Spring is in the Air

At the home of OPSIS, the phrase ‘spring is in the air’ is an established saying which means long-awaited warmer and longer days and the sense of a new beginning. But what’s in the air in the spring, really? Let’s take a look at seasonal variations of air pollution!
Read More »
Good Averages, on Average?

Good Averages, on Average?

We all know how to calculate the average of a set of values: add the individual values and then divide by the number of them. Right? Yes, almost always right, but if you work with air quality and specifically meteorological data, you must sometimes think a little further.
Read More »
Regulating Mercury Emissions

Regulating Mercury Emissions

Have you heard of new and strict regulations on mercury emissions within the European Union? If you are responsible for the operations at a waste incineration facility, you probably have. But what’s the issue with mercury, and what do the EU regulations say?
Read More »
Pollutants in Emissions to Air – What’s in the Smoke?

Pollutants in Emissions to Air – What’s in the Smoke?

Back in the nineteenth century or so, industries pouring out smoke through the stacks were considered signs of progress and prosperity. However, that changed when the effects of the emissions became apparent, including smog, acid rain, and respiratory diseases. Nowadays, the smoke is usually much cleaner thanks to more efficient production processes and flue gas treatment, but there’s still smoke. What’s in it?
Read More »
Keep an Eye on Ozone

Keep an Eye on Ozone

Stratospheric ozone is a blessing. It prevents most of the sun’s ultraviolet radiation from reaching the surface of the earth, and thereby protects surface-dwelling life from damaging UV rays. At the same time, ground-level ozone is a major air pollutant. Let’s take a closer look at the latter phenomenon.
Read More »
Page 2 of 7 First 1[2]345 Last

Archives

Categories