BAM-1022 Beta Attenuation Mass Monitor

The Met One Instruments, Inc. BAM 1022, Real-Time Portable Beta Attenuation Mass Monitor, continuously measures the mass concentration of ambient particulate matter collected onto glass filter tape with time resolution of one-minute. The BAM 1022 employs an in-line sampling geometry in which the attenuation of beta rays across filter media is measured and particulate matter is sampled simultaneously. This allows ambient sampling to occur for virtually 60 minutes each hour. It also allows for beta ray measurements to be made for virtually the entire hour thereby improving sensitivity and time resolution.

The BAM 1022 employs a unique “in-situ” sampling technique where the beta measurement is kept at a near fixed temperature above ambient conditions, thereby minimizing measurement error due to loss of semi-volatile particulate material or due to excessive moisture in the sample stream. Highly accurate measurements are made without having to employ expensive Nafion dryers thereby increasing reliability and decreasing operating costs. The integrated shelter does not employ air conditioning, nor does the sampling system employ flow splitters. This results in easier service, enhanced reliability and lower power consumption.

The BAM 1022 comes integrated into its own lightweight equipment shelter with easily detachable pump box making it ideal for installation in areas where no permanent structure or walk-in shelter is available. Power consumption is modest as no air conditioning is required. No component weighs more than 40 lb. meaning that it is easily transportable by one person. The entire system may be set up and put into operation in less than ten minutes.


The BAM 1022 has US-EPA designation for PM2.5 (EQPM-1013-209) for which a dedicated hourly output channel is available. A second, real-time output channel will provide the user with continuous PM updates down to 1-minute time resolution. The BAM 1022 is ideal for the following applications:

  • Criteria-Grade Air Quality Surveillance Networks
  • Near-Roadside PM Monitoring
  • Rapid-Deployment Applications Such As Emergency Responder and Controlled Burn Work
  • Research and Development

Advanced Features

  • In-Situ measurement of PM that provides high accuracy, minimal measurement artifacts.
  • Reduced background determination frequency.
  • Unsurpassed performance under high ambient dew point operation.
  • Advanced communications features allowing remote operation and cloud-based communication.
  • Advanced diagnostics.
  • Improved sensitivity compared to other in-line beta attenuation mass monitors.
  • Meteorological and other sensor inputs.


Measurement Principle: Beta Attenuation
US EPA Designations: EPA Class III Federal Equivalency Method (EQPM-1013-209)
Measurement Range: -15 μg/m3– 10,000 μg/m3
Accuracy: Meets US-EPA Requirements for Class III PM2.5 FEM
Data Resolution: 0.1 μg/m3
Lower Detection Limit: < 2.4 μg/m3 (Hourly, 2σ) / < 0.5 μg/m3 (24 Hour, 2σ)
Sampling Time: Continuous Air Sampling with Hourly Tape Advance
Measurement Cycles: Primary: Automatic Hourly PM Measurement
(Required for PM2.5 FEM Operation)
Secondary: User Selectable Short Term Averages
(1, 5, 10, 15, or 30 minute)
Sample Flow Rate: 16.7 liters/minute
Filter Tape: Continuous glass fiber filter, 30mm x 21m roll.
Up to 2 months operation per roll.
Maintenance Interval: 8 Weeks (minimum)
Span Check: 14C (carbon-14), 60 μCi ±15 μCi (< 2.22 X 106 Beq),
Half-Life 5730 years.
Detector Type: Scintillation Photomultiplier Tube
Operating Temperature Range: -30° to +50° C
Operating Humidity Range: 0 to 90% RH, non-condensing
Enclosure: Instrument is integrated into its own,
weatherproof enclosure and sits on a separable, pump box
Analog Output: Two channels; optically isolated; switch settable voltage or
current0-1, 0-2.5, 0-5 VDC / 0-20, 2-20, 4-20 mA
(Hourly Concentration and/or or User Selectable Short Term Average)
Serial Interfaces: Continuous Air Sampling with Hourly Tape Advance
Sampling Time: Continuous Air Sampling with Hourly Tape Advance
Sampling Time: 1 channel; full duplex RS-232, USB, and Ethernet serial
(Shared common serial output) Baud rates 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200
Compatible Software: CometTM (included), Air PlusTM, terminal programs such as HyperTerminal®
Data Logger Memory: 108,134 records (12.5 years @ 1 record/hr. 75 days
@ 1 record/min)
Power Supply: 100 – 230 VAC; 50/60 Hz universal AC power
Power Consumption: 300W (Incl. BAM-1022, Inlet Heater, BX-126 or BX-127 Pump,
and Vent Fan)
Approvals: NRC, ISO-9001, ROHS, US-EPA

Specifications are subject to change at any time