BT-645 Portable Dust Monitor

The BT‐645 Portable Dust Monitor has been designed to continuously measure and record particulate information for indoor work place and public place environments.


The BT-645 optical sensor, matched electronics and backlit display, are enclosed in a rugged metal enclosure to protect the instrument from normal daily use.


The BT-645 laser optical sensor is used to detect and measure particulate concentrations up to 100 milligrams per cubic meter. The continuous flow optical sensor is combined with purge air to ensure accurate measurements in adverse environments. The internal datalogger will store over 5,000 samples. Sample history events can be viewed on the display or downloaded to a computer using Comet software. The BT-645 internal battery pack provides over 10 hours of continuous operation. Battery recharge time is approximately 2.5 hours. The standard unit is supplied with a TSP inlet. Optional sampling inlets are available for PM2.5, PM4 and PM10.


  • Rugged Design
  • Real Time Monitoring
  • Sample History
  • Low Cost w/ Data Logging
  • Purge Air System


  • Public/Workplace Monitoring
  • Indoor Air Quality
  • ndustrial/Occupational Hygiene


Concentration Range: 0 to 100 mg/m3 (0 to 100,000 µg/m3 )
Sensitivity: 1 µg/m3
Accuracy: 5% traceable to standard with 0.6 µm PSL
Measuring Time: 1, 5, 10, 15, 30 and 60 minutes
Flow Rate: 2 LPM
Sensitivity: 0.3 μmm
Flow Rate: 1.0 cfm (28.3 lpm)
Note: Measurement accuracy requires use of appropriate K‐factor for the material being measured.
Light Source: Laser diode, 5 mW, 670 nm
Power: 14.8V Li‐ion (Lithium Ion) battery pack
Battery Life: Over 10 hours contnuous operation
AC Adapter/Charger: Li‐ion battery charger, 100 – 240 VAC, 50/60Hz to 16.8 V @ 1.8 A
Communications: RS-232, USB
Data Storage: Over 5,000 samples
Display: 4 X 20 LCD
Keyboard: 6 key membrane type
Cont. Operating Time: 10 hours
Recharge Time: 2.5 hours
Software: Yes
Power Supply / Charger: Yes
Size: Height = 4.25” (10.8 cm)
Width = 7.44” (18.9 cm)
Thickness = 3.25” (5.4 cm)
Weight: 3.7 lbs (1.7 kg)
Operating Temperature: 0 ̊ C to +50 ̊ C
Relative Humidity: 90% (non‐condensing)
Storage Temperature: -20 ̊ C to +60 ̊ C
Supplied: User Manual
USB Cable
Communications Software (Comet)
AC Adapter / Battery Charger
Optional: PM2.5 Sharp Cut Cyclone (SCC‐112)
PM10 Sharp Cut Cyclone (SCC‐110)
Custom Serial Cable (PN 3228)

Specifications are subject to change at any time