Single Channel Tricolor Absorption Photometer

Model 9406


The Single Channel Tricolor Absorption Photometer (STAP) allows you to perform aerosol light absorption measurements on-board Unmanned Aerial Vehicles (UAV) and other mobile platforms where high sensitivity and time resolution are critical. Capable of 1Hz measurements, the system is compact, light and uses minimal power. The STAP uses light transmission through two small filters to derive the light absorption coefficient, from which the black carbon mass concentration can be calculated for an assumed mass absorption efficiency. The unit offers one of the best detection limits on the market (20 ng/m3 black carbon). Development of the STAP is built upon BRECHTEL’s years of experience with our traditional light absorption instrument (Model 2900 TAP). Deploy the 9406 in conjunction with our other portable instruments to get a more complete picture of the aerosol under study.

Key features:

  • Three wavelengths
  • Extremely sensitive (noise level 20 ng/m3)
  • Portable, lightweight, low power use
  • Reference filter channel
  • Self-contained with on-board data storage
  • No external pump required
  • Field tested on unmanned aerial vehicles (UAVs)

Technical Specs

9406 STAP Technical Specs

parameter value
Wavelengths 450, 525, 624 nm
Sample flow 0.5 to 1.7 lpm
Noise level (1 sigma) +/- 0.2 Mm-1 (0.02 μg/m³ black carbon mass)
Filter Glass fiber, 10 mm dia
Size 5.3 x 4.3 x 3.9 in/13.5 x 10.9 x 9.9 cm
Weight 1.45 lbs/0.66 kg
Supply voltage 12 VDC
Power 10 Watts
Mounting Multiple hard mounting points through metal body brackets

Copyright ©2017 All specifications are subject to change without notice. BMI assumes no responsibility for inaccuracies in this document or for any obligation to update information in this document. BMI reserves the right to change, modify, transfer or otherwise revise this publication without prior notice.

*Some products may be shown with optional accessories, which are sold separately. Items shown may not be to scale.

Applications and Solutions

  • Mobile platform sampling: UAVs, Balloons, Aircraft, Vehicles
  • Black carbon monitoring
  • Personal exposure monitoring
  • Climate change field studies
  • Air quality monitoring


Integrated software drives each ACCESS module from the inside – the built-in microprocessor and sensors are able to sense, control, and report on instrument performance. A serially-communicated stream of data provides real-time user access to all the fundamental operating parameters and measurement values. An on-board micro-SD card can be used to store data locally.

Add the Base Module option to your ACCESS package to benefit from a graphical user interface (GUI) that allows you to easily interact with the instrument so you can change parameter settings, configure outputs and view measurements on the screen of the PC. Multiple ACCESS modules can be connected via a micro-USB hub to the GUI allowing the system configuration to be easily changed. This feature also allows each of the connected modules to be remotely controlled via a single RS232 connection.The GUI software automatically recognizes which instruments are attached to the Base Module and adjusts accordingly. It is provided to facilitate configuration and monitoring of the ACCESS instruments on the

The GUI software automatically recognizes which instruments are attached to the Base Module and adjusts accordingly. It is provided to facilitate configuration and monitoring of the ACCESS instruments on the ground, but is not required to operate the unit and acquire data. The external GUI software is only available pre-loaded on a ruggedized tablet PC supplied by BRECHTEL.

What’s Included

  • Model 9406
  • LED Display
  • External 12 VDC power supply
  • Communication and power cables
  • Operating manual
  • Weatherproof shipping case


The following optional accessories are available:

9406 STAP Accessories

Part Number Description
STAP-FIL250 Package of 250 10mm glass fiber filters for 9406 STAP
ACC-STAPKit Maintenance kit for 9406 STAP
ACC-PWR External 12VDC power supply for ground operation of any 94XX series instrument
ACC-PC Computer with 94XX series control software

Related Products

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