2i, 2i-N Digital Aerosol Photometer

The most advanced, innovative and user friendly digital aerosol photometer available today, the 2i Digital Photometer is portable, yet rugged, and the ideal instrument for in-situ filtration system integrity testing. The iProbe, a handheld scanner with local LCD display and controls, enables the operator to change settings without stopping to adjust the base unit, minimizing downtime.


  • Independent filter certifiers
  • Nuclear facilities
  • Pharmaceutical manufacturers
  • Medical facilities and cleanrooms
  • Biosafety cabinets and fume hoods

Key Features & Benefits

  • Lightweight, portable and rugged digital photometer
  • Large 4.3 in. LCD screen to display critical information
  • iProbe (optional) with 12 ft cable for hard to reach areas minimizes downtime
  • User settable aerosol noise suppression for more stable aerosol measurements
  • Printer (optional) available for reporting
  • 2i-N models include a sealed sample train, allowing for the safe removal and replacement of contaminated sampling components
  • 2i-N models are compatible with ASME N511, ASME 510, ASME 509 & ASME AG-1

Innovative User Interface

The 2i base instrument’s 4.3 in. LCD gives life to the easy to use, menu driven interface. Aerosol measurements and pump sampling rates are prominently displayed for easy viewing. System parameters and selections such as alarm types, alarm set points and aerosol reagent are shown on the lower menu bar, while icons at the top of the screen give the status of connected peripherals, reporting functions, and aerosol noise suppression selections.

Data Reporting

Three unique report functions are now available with the 2i through the USB or optional thermal printer interface. Continuous mode offers the same output as ATI’s legacy photometers to ensure backward compatibility. Monitoring mode provides the ability to collect data at user defined intervals for long term sampling. Summary mode, which gives discrete reporting capability for individual filter locations, can output to the thermal printer to meet customer documentation requirements.


The iProbe with a 12 ft cable acts as an extension of the base instrument through a nearly identical user interface. All status and selection icons from the base unit are represented on the iProbe. With the press of a button, the sampling location can be remotely selected and switched by way of an electronically controlled valving system.

Performance Guaranteed

To ensure consistent results in all applications and altitudes, the sampling flow rate is constantly monitored and controlled via a pulse width modulated pump. The 2i has been independently tested and qualified to ensure compliance with all applicable electrical and safety requirements.

Simple Maintenance

Annual NIST traceable calibration service is provided by ATI or an ATI-certified calibration facility. Calibration includes setting the aerosol reagent references, sample flow reference points, operating voltages, and servicing the light scattering chamber assembly. Routine preventative maintenance entails cleaning and inspection of internal sample tubing and connections, the internal reference filter, and iProbe.

Hazardous Environments

Designed for the rigors of nuclear and other hazardous applications, the 2i-N (the nuclear version of the 2i) is equipped with a unique, sealed sample train. The unit is engineered to allow safe removal and replacement of contaminated sampling components.

Enhanced Features

Upstream aerosol mass concentrations are displayed in actual mass concentration values of micrograms per liter (μg/l). User settable Aerosol Noise Suppression (ANS) allows for more stable aerosol.

# Description Part Number
As Shown 2i: Ensemble 120V or 240V 9300235 or 9300240
As Shown 2i-N: Ensemble 120V or 240V 9300244 or 9300245
Not Shown Power Cord, NEMA 5-15 120V or CEE 7/4 240V 6700001 or 6700133
Not Shown O-Rings 4300002/4300003/4300134
Not Shown Lint Screen 550011
Not Shown Operations and Maintenance Manual 1800224
Product Specifications
Dimension (L x W x H) 25.7 cm x 33 cm x 15.2 cm (13 in. x 10.1 in. x 6 in.)
Weight 8.6 kg (19 lb)
Output Voltage 100 to 250 Volts AC, 50/60Hz automatic adjustment
Input Voltage 0.5 amps @ 120V, 0.25 amps @ 240V
Auto Zero Automatically establishes zero reading at startup
Alarm User selectable audible, visual, and vibratory
alarms notify the user when the user defined set
point is exceeded.
Flow Control Pulse Width Modulation (PWM) control ensures
sampling rate of 1cfm (28.3 lpm) +/- 10% in all
Reagent Settings PAO-4, DOP, DOS/DEHS, Ondina, PEG, Krydol,
Corn Oil, Mineral Oil, Paraffin
Dynamic Range 0.0001 mg/m3 to 120 mg/m3
Sensitivity 1% of readings > 0.01% to 100%
Repeatability 0.5% of readings > 0.01% to 100%
Light Source Solid State, rated for life of instrument
Output USB Connection
Reporting Continuous, Summary, and Monitoring modes
Standards Compliance
Industry NSF 49, IEST, ISO 14644-3
Electrical & Safety CE, FCC, EN 61010-1:2010, EN 61326-1:2006


2i Digital Aerosol Photometer Accessories
# Description Part Number
1 Thermal Printer 9300249
2 Carry-On Case 9300258
3 iProbe Scanning Probe with 12 ft cord 9300248
Not Shown Wheeled Carrying Case 9300243
Part Number & Ordering Information
2i, 2i-N Photometer & Accessories Description Part Number
2i Digital Photometer (120v) 9300241
2i Digital Photometer (220v) 9300242
2i-N Digital Hazardous Environment Photometer (120v) 9300246
2i-N Digital Hazardous Environment Photometer (220v) 9300247
iProbe iProbe 9300248
2i Printer 2i Printer 9300249
2i Case – Small Heavy Duty Case Heavy Duty Transport Case (Small, no wheels). Accommodates 2i or 2i-N and iProbe 9300258
2i Case – Large Heavy Duty Case Heavy Duty Transport Case (Large, wheels). Accommodates 2i or 2i-N, iProbe, and Printer. 9300243
2i Ensemble 2i Photometer (110v), iProbe, Heavy Duty Transport Case (Small, no wheels). 9300235
2i Ensemble 2i Photometer (220v), iProbe, Heavy Duty Transport Case (Small, no wheels). 9300240
2i-N Ensemble Digital Hazardous Environment Photometer (120v), iProbe, Heavy Duty Case (Small, no wheels). 9300244
2i-N Ensemble Digital Hazardous Environment Photometer (220v), iProbe, Heavy Duty Case (Small, no wheels). 9300245