The Aurora PM Correlating Nephelometer is part of the ‘new generation’ nephelometers using a single wavelength to measure aerosol light scattering and derive particulate concentrations.

The Aurora 2000 is available in two configurations.

1. Configured with a PM2.5 Size Selective Inlet (SSI) to sample PM2.5, ideal in areas with stable aerosol chemistry
2. Configured to communicate directly with a BAM1020, providing 1 minute PM corrected data, ideal in areas with multiple aerosol sources

• New high powered LED light source increasing accuracy and reliability (red 635nm, blue 450nm, green 525nm)
• Compact and portable (light weight)
• Smart heater for controlling relative humidity of sampled air
• 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

The Aurora 1000F is available with automatic flow control and a PM2.5 Size Selective Inlet. This configuration improves the correlation between the Aurora 2000 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) PM2.5 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”.

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 (PMBAM). These hourly averages are compared to the Aurora’s hourly average scattering coefficient (σscat) and a scattering to PM coefficient factor (CoefScat/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 (PMaurora). This data can also be used to determine changes in aerosol source through deviations in light scattering from the expected values.

Aurora 2000 nephelometer parameters:

• U.S. EPA compliance data for PM measurement
• Scattering coefficient (σscat)
• BAM1020 PM averages – 1 hour average only
• Corrected Real time 1 minute PM concentrations PMaurora
• Sample Temperature, Relative Humidity and Barometric Pressure

It is also possible to perform basic source apportionment work using data generated by the Aurora Nephelometer as although the scattering coefficient to mass factor CoefScat/PM isn’t logged by the Aurora Nephelometer it is output from the Aurora’s RS232 port and can also be backward calculated by comparing PMBAM with PMaurora on an hourly basis.

A shift in this factor indicates that the aerosols chemistry has changed and for instance marine air is now being measured instead of urban air. This information can be useful in estimating the degree of harm that PM concentrations may cause to human health as urban air may pose significantly higher risks than marine air.

Range: 0.03 to >20 000 Mm-1, 0-1000 ug/m3
LDL: 0.3 Mm-1, 0.5 ug/m3
Temperature range: -20 to 45oC
Sample flow rate: 3 l/min approx
Weight: 12 kg
Dimensions: 170 x 700 x 215 mm (LxWxH)
Power 100-240 VAC, 50/60 Hz or 12VDC

• Comm ports include
  • 4 analogue outputs (2 voltage & 2 current)
  • RS232 multidrop
  • RS232 serial port
• Data Storage: 10 days of 1 minute averages or 51 days of 5 minute averages

User friendly and easy to maintain, the Aurora 2000 makes PM2.5 correlation studies simple and easy to perform.

The Aurora 2000 is part of the ‘new generation’ nephelometers using a single wavelength to measure particulate scattering. The Aurora is available in two configurations:

Configured with a PM2.5 Size selective inlet (SSI) to sample PM2.5, Ideal in areas with stable aerosol chemistry

Configured to communicate directly with a beta attenuation particulate monitor providing 1 minute PM corrected data, ideal in areas with multiple aerosol sources

Increased accuracy

• Automatic optical reference calibration
• Enhanced high powered LED light-source
• PM2.5 sampling inlet head

Ease of use

• Compact and portable
• Automated instrument calibration using the selected span gas, with pressure and temperature compensation
• Internal sample heater which can be enabled by the user to eliminate the effects of humidity (RH: <40% to <90%)
• Automatic zero/span (check or adjust) available in intervals of 1,3,6,12, 24 hrs or weekly
• Holds up to 45 days of 5 minute data averages or 10 days of 1 min data averages
• Data downloader and firmware upgrade software supplied on CD

Lower cost of ownership

• Internal 12V heater eliminates the need for expensive external inlet heater
• Long lasting LED light source reduces replacement costs