Series 9100
Computerized Ambient Monitoring Calibration System

The Environics® Series 9100 Computerized Ambient Monitoring Calibration System is an advanced microprocessor controlled instrument for dynamic calibration of ambient air analyzers.

Features include:

  • Output concentrations as low as 5 ppb
  • Ability to easily set concentration directly in ppb
  • Flow adjustable from 2 LPM to 20 LPM (depending on setup)
  • Temperature & Pressure compensation

The Environics 9100 is the unit of choice in the Air Quality Monitoring Programs of the EPA and California Air Resource Board (CARB)

Ambient Monitoring Calibration

Read more about their protocols at:

CARB - Standard Operating Procedures for Air Quality Monitoring, Appendix AC, Environics Series 9100 Gas Calibrator

EPA - Standard Operating Procedures, Environics Series 9100 Computerized Ambient Monitoring Calibration System, Version 0.01

The Series 9100 automatically performs zero, precision, span and multi-point calibrations using NO, NO2, SO2, CO, O3, hydrocarbons and other gases of interest. The Series 9100 exceeds all U.S. Environmental Protection Agency requirements.

** Now available with a 3rd Mass Flow Controller!  Learn more about this enhancement.**

The Series 9100 consists of a single chassis supporting up to 3 thermal mass flow controllers, an ozone generation module, a mixing zone, a reaction chamber for gas phase titration, and control electronics.

Commands are entered from the front panel and displayed on a backlit 25 line by 80 character liquid crystal display. The instrument may also be operated using contact closures or an RS-232 serial data interface.

The mass flow controllers are calibrated to a NIST (National Institute of Standards and Technology) traceable primary flow standard. The calibration data consists of a comparison of desired versus actual flow over the full dynamic range of the instrument, with linear interpolation between points. Calibration data is stored in the non-volatile memory and may be updated by the user with a suitable standard.

The Series 9100 ozone generator is factory calibrated using a NIST traceable ozone standard. This temperature controlled, ultra-violet (UV) based ozone generator includes a precision photo-optical feedback circuit to compensate for lamp aging effects as well as built-in pressure compensation.

The Series 9100 is available in either a standard 19" rack mount or bench top configuration.

Download Full Datasheet for Series 9100 (pdf)


  • 25 line by 80 character display permits editing and viewing of an entire seven-day schedule of calibration events in worksheet format.
  • Automatic calculation of dilution and span gas flows based on commanded concentration eliminates the need for manual computation and allows rapid transition from point to point.
  • Internally-stored mass flow controller calibration data improves accuracy by as much as a factor of ten and simplifies field recalibration.
  • Internally-stored ozone generator calibration data insures linear, repeatable ozone generation without photometer control. Ozone generator performance exceeds U.S. EPA criteria for ozone transfer standards.
  • Ozone generator pressure compensation insures repeatable ozone generation at a flow rate and back pressure other than that at which it was originally calibrated.


The Series 9100 has six primary routines.

  • Concentration Mode: User enters Target Output Gas Concentration (ppm or %) for the span gas. The actual concentration is displayed during mixing.
  • Flow Mode: User enters Target Flow Rate (cc's or liters per minute) for the span gas and dilution gas. Actual flow rates are displayed after mixing is initiated.
  • Volts Mode: User enters a command voltage to the mass flow controller and the ozone generator. The actual voltage is displayed during operation.
  • Program Mode: Permits multi-event programming and unattended automatic operation of the instrument over a seven-day schedule.
  • Calibrate Mode: User enters new calibration data for each mass flow controller and ozone generator. (Can be password protected)
  • Maintain Ports: User enters the name of the span gas in the source cylinder, its concentration (ppm) and the port to which the cylinder is connected.


Mass Flow Controllers (as a percent of setpoint)*


From 10 to 100% of Full Scale Flow
Concentration: ± 1.0%
Flow: ± 1.0%
Flow Repeatability: 0.05%

Warm up time: 30 minutes
Response time: 30 seconds to ±2.0% of Setpoint

*Mass flow controllers are calibrated using a NIST Traceable Primary Flow Standard, using a reference temperature of 25°C (77°F) and a reference pressure of 760 mm Hg (29.92 in. Hg).

Ozone Generator:

Concentration Range: 0.5 - 1.25ppm at 10 slpm; 5ppb to 400 ppb at 16 to 20 LPM
Accuracy: ±2% or ±0.005ppm at 10 slpm
30 day repeatability: ±2% or ±0.005ppm


Balance: One external ¼" Swagelok*
Span(s): One external ⅛" Swagelok*

One external ¼" Swagelok*
* (or compatible fitting)

Operating Pressures at inlets (flow dependent)
Minimum: 10 psig (0.67 Bar)
Recommended: 25 psig (1.68 Bar)
Maximum: 150 psig (9.87 Bar)

Wetted Surfaces
Tubing: Teflon
MFC's: Stainless Steel
Seals: Viton®

Operating temperature: 32° - 122° F (0° - 50° C)
Performance temperature: 59° - 95° F (15° - 35° C)

Minimum: 35 lbs. (16 Kg.)
Maximum: 40 lbs. (18 Kg.)

Dimensions (w x h x d)
Portable: 17" x 7" x 23.5"
(43.18 cm x 17.78 cm x 59.69 cm)

Rack: 19" x 7" x 23.5"
(48.26 cm x 17.78 cm x 59.69 cm)


Standard: 115 VAC (100 to 130 VAC), 50/60 Hz
Optional: 220 VAC (200 to 260 VAC), 50/60 Hz
Current: 3 Amps (maximum)


Inmos T 400 series, 32 bit processor
12 bit A/D and D/A conversion

Operating Modes

Front panel membrane keypad
Internal timer control
Optional RS-232 serial data interface
Optional Status board interface
Other communications options available

Data Output

Optional RS-232 port serial data interface
Optional Parallel printer port (Centronics compatible)


  • Rack Mount
  • Extra Gas Inlets (maximum of six total)
  • Additional MFC (maximum of three total)
  • RS-232 Serial Data Interface
  • Solenoid Valve on Output
  • Status Board
  • Permeation Oven
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