PAAS-4λ · Product brochure
PAAS-4λ brochure
Measurement concept, applications and technical specifications.
BLACK CARBON & AEROSOL MONITORING
PAAS-4λ
Photoacoustic Aerosol Absorption Spectrometer
A direct view of aerosol absorption.
Measure aerosol light absorption directly at up to four wavelengths. PAAS-4λ brings photoacoustic measurements to black carbon monitoring, aerosol research, and long-term atmospheric observations.
- Measurement
- Aerosol absorption
- Wavelengths
- Up to four
- Detection limit
- 0.5 Mm⁻¹
MEASUREMENT & APPLICATIONS
Built for your research.
Applications
- Black and brown carbon observations
- Air-quality monitoring networks
- Combustion source studies
- Aerosol ageing and field research
How it works
Light absorbed by aerosol particles produces a periodic heating signal inside an acoustic resonator. A microphone detects the resulting sound, providing a measurement of aerosol light absorption. Multiple laser wavelengths share a single measurement cell.
Direct measurement
Photoacoustic detection measures the absorption of suspended aerosol particles.
Spectral information
Up to four wavelengths help characterize light-absorbing aerosols.
Station integration
Separate optical, electronics and flow units fit into 19-inch rack enclosures.
INSTRUMENT DETAILS
Technical specifications.
Measurement
| Measurement principle | Photoacoustic aerosol absorption |
|---|---|
| Aerosol fraction | PM₁ |
| Wavelengths | Up to four; configurable |
| Example wavelengths | 405, 515, 660 and 785 nm |
| Detection limit | 0.5 Mm⁻¹ |
| Accuracy / precision | 10% / 3% |
| Sampling / typical averaging | 1 second / 60 seconds per wavelength |
| Sample flow | 0.5–2 L/min |
| Cell volume | 236 cm³, including acoustic buffers |
| Acoustic resonance | 3200 Hz |
Integration
| Typical power consumption | 180 W |
|---|---|
| Optical unit | 462 × 422 × 210 mm; 27 kg |
| Electronics unit | 496 × 449 × 310 mm; 17 kg |
| Flow unit | 436 × 449 × 177 mm; 5 kg |
| Data acquisition | Graphical control software and SQL data storage |
Wavelength selection and instrument configuration can be adapted to the measurement task. Contact us to discuss your station or experiment.
READ FURTHER
Downloads & references.
Download PDFPDF · 2.1 MB
PAAS-4λ · Research publication
The four-wavelength Photoacoustic Aerosol Absorption Spectrometer
Schnaiter et al. · Atmospheric Measurement Techniques · 2023
Publisher & DOI ↗LET’S TALK SCIENCE
Discuss your measurement.
Tell us about your application, platform or configuration requirements.