Nephelometers

Ecotech and its American partner American Ecotech have concluded its exhibition of the Aurora Nephelometer at the AAAR Annual conference in Portland, Oregan. The conference had a wide variety of aerosol studies including light scattering and light backscatter.

The perspex nephelometer and Aurora nephelometer will next be displayed at AWMA in the U.S.A.

Ecotech will again present its unique perspex nephelometer at the AAAR annual conference in Portland Oregan, demonstating the actual inner workings of a nephelometer and how the Aurora Nephelometer uses its backscatter shutter to measure polar scatter at various angles.

The AAAR 29th annual conference will be held at the Oregon Cnvention Center in Portland Oregon from the 25-29 of October 2010.

After the success of Ecotech's Aurora Nephelometer at the IAC aerosol show in Finland, Ecotech with its American Partner American Ecotech will be showcasing its nephelometer range at the AAAR annual conference.

Ecotech will again present its unique perspex nephelometer, which allows viewers to see the action of the unique three wavelenght LED light source, and the innovative backscatter shutter allowing polar measurements of light scatter

Ecotech Pty Ltd are showcasing the Aurora Nephelometer at IAC 2010 International Aerosol Conference with a special demonstation. Ecotech have developed a unique perspex nephelometer casing that allows viewers to see the actions of alternating LED light transmission as well as the use of a backscatter shutter to block light from 90 degrees.

Another extra special bonus with this demonstration is the ability to show the backscatter shutter blocking light at other angles, allowing the measurement of particulate backscatter with a polar nephelometer.

For more information on the show visit www.iac2010.fi

Ecotech Pty Ltd have released a new low powered data logger which can be used with a 12V power source and is ideal for remote locations.

The WinAQMS Mini DAS will be a great data logger for meteorological stations as well as remote nephelometer sites or nepehleometers in all weather containers.

Ecotech has announced that backscatter measurements are now supplied standard for all Aurora 3000 Integrating Nephelometer.

The backscatter feature of the Aurora 3000 nephelometer is achieved through the use of a backscatter shutter mounted on the light source housing inside the cell. This shutter moves between two locations in and out of the optical path of the light source (90° to 180°) within the light sources Lambertian distribution.

The position of the backscatter shutter is controlled to within ±0.09°, and can be adjusted to achieve other cutoff angles if required for more advanced analysis of backscatter.

The ability to remove and measure the entire light source including the backscatter with the one module has been applauded by a number of customers using the instruments for research applications.

More information can be found at: www.ecotech.com

The recent eruptions from an Icelandic volcano and its affect on stopping most air traffic in Europe has given a unique chance for scientists to measure global radiation balance. Scientists can measure the difference aerosols (from air traffic) have on light scatter but will also need to eliminate the affects of the volcano ash as mentioned in an article from Alister Doyle, Reuters.

These measurements are made with a backscatter nephelometer or a polar nephelometer and measure the amount of light that jet streams reflect back into space.

A nice video showing the magnitude of air traffic in europe demonstrates just how important understanding jet streams effect on global dimming really is.

A new nephelometer website has be launched at www.aurora-nephelometer.com. This website is designed to provide information about the aurora nephelometer series, their benefits, advantages, how they work and various applications. It will also incorporate links to various studies involving nephelometers as it is continually upgraded.

To have a look yourself visit www.aurora-nephelometer.com

Global Dimming or Global warming? a BBC documentary
An interesting documentary about global dimming describing how aerosols in the air are reflecting light back into space and reducing the solar energy reaching the earth, masking the effects of Global warming. The Nephelometer is the principal instrument used to measure backscatter of light back into space and global diming.

Recently the American Association for Aerosol Research (AAAR), co-sponsored by the Air & Waste Management Association, held the 3rd International speciality conference "Air Pollution and Health: Bridging the gap from sources to health outcomes".

This conference was attended by many health officials, aerosol researchers and instrument manufacturers and provided a forum with which information could be shared and relationships formed.

Ecotech, in association with its distributor American Ecotech, attended the conference displaying the Aurora Nephelometer to attending parties. Ecotech's representative was Head of Research and Development Mr Grant Kassell. Mr Kassell met with many eminent aerosol and atmospheric researchers and discussed ways in which the measurement of light scattering and global dimming can be better performed. These discussions involved how instrumentation, such as the nephelometer, can be improved to enhance the information that they produce.

We hope that this conference, and these meetings, will help improve the performance and broaden the scope of what nephelometers are capable of in air quality and global dimming studies.

The Aurora 2000 PM correlation nephelometer uses a single wavelength to measure aerosol light scattering and derive particulate concentrations. The Aurora 2000 nephelometer is available in two configurations.
PM2.5 Size Selective Inlet (SSI) to sample PM2.5, ideal in areas with stable aerosol chemistry Communicates directly with a BAM1020, ideal in areas with multiple aerosol sources

More info at = www.ecotech.com

---

Configuration 1

The Aurora 2000 nepheleometer is available with automatic flow control and a PM2.5 Size Selective Inlet. This configuration improves the correlation between the Aurora 2000 nephelometer and Federal Equivalent PM2.5 Methods.

This sampling method enables a manual correction factor to be entered in order to derive real time (1 minute) PM_2.5 concentrations. In applications where the aerosol chemistry is stable this configuration provides excellent results with minimal maintenance and a high degree of correlation.

The Aurora Nephelometer employs a smart heater controlled by a relative humidity sensor, this allows the user to set the maximum relative humidity of the sampled air, eliminating the influence of water vapour on the measurement and thus performing a “dry measurement”.

---

Configuration 2

In applications where aerosol chemistry is subject to change, a correction factor derived from manual sampling may be unreliable.

The Automatic correlation PM nephelometer connects directly to the Met One BAM1020 in order to monitor and log PM hourly averages generated by a BAM1020 (PM_BAM). These hourly averages are compared to the Aurora nephelometer’s hourly average scattering coefficient (σ_scat) and a scattering to PM coefficient factor (Coef_Scat/PM) is calculated. This factor is then applied to the next hour of 1 min scattering coefficients measured in order to determine a 1 minute average for PM concentrations (PM_aurora). This data can also be used to determine changes in aerosol source through deviations in light scattering from the expected values.

The Aurora 1000 nephelometer is the ‘new generation’ integrating nephelometer which uses a single wavelength for visibility measurements at one of three user specified wavelengths

• 450nm (blue) for fine and ultra fine particulates (wood fires, automobiles)
• 525nm (green) for visibility
• 635nm (red) for large particulates (e.g. pollen, sea salt)

Differentiated in the marketplace by Ecotech’s innovative LED Light source design, the Aurora 1000 nephelometer provides higher reliability and stability in measuring local atmospheric visibility.

Features

• New high powered LED light source increasing accuracy and reliability (red 635nm, blue 450nm, green 525nm)
• Compact and portable (light weight)
• Reduced power consumption and a lower carbon footprint due to:
  • Low powered internal heater
  • New 12v power source
• Automated instrument calibration using zero and span gas
• Pressure and temperature reporting