Peroxide Monitor

The Guided Wave H₂O₂ Vapor Monitor is a turnkey solution for the measurement of hydrogen peroxide and water vapor concentrations. Because it operates in real time, this monitor takes the guesswork out of determining the hydrogen peroxide vapor level during cycle development and throughout the actual sterilization cycle. The process engineer now has continuous, accurate data for documentation of the cycle.

Proven Technology

Guided Wave has been measuring hydrogen peroxide vapor concentrations for several years using our near infrared (NIR), fiber optic scanning spectrophotometers. Once the specific wavelengths for H₂O₂ and H₂O were determined, a simpler, non-scanning analyzer could be developed for this application. This new design uses fixed wavelength technology but still incorporates dual beam design for stability and accuracy. Fiber optic cables take the light to the isolation chamber and back to the analyzer, the virtual equivalent of vapor sampling. This monitor measures to within 0.1 mg/l of H₂O₂.

Easy Operation and Control

The monitor is controlled via the touch pad or through the RS232 communications port with simple to use operational commands. Password protection allows for two different levels of access: operator and administrator. All of the analytical calculations are encoded in the firmware -- there is no advanced or field programming required.

Quick Installation and Start-up

The system is packaged with everything needed to start monitoring. Included are: the analyzer, the probe, a pair of fiber optic cables to connect the probe to the analyzer, a comprehensive operations manual, power cable and even a communications cable to connect to your PC. There are no extras to buy; you just unpack, plug it in, warm it up, install the probe, and start to monitor. There is virtually no start-up learning curve.

Factory Calibrated

Normally, spectrophotometers are calibrated by comparing the spectral results against an accepted wet chemical method. This analyzer was calibrated by comparing concentration readings versus theoretical calculations and two wet chemical methods commonly used to measure H2O2 vapor concentrations (Pharmaceutical Engineering, July/August 1998, Vol. 18 No. 4). Once the chemical and physical constants were determined and encoded into the firmware, the only way the analyzer could fall out of 'calibration' is if the photometric properties of the instrument change.

Failsafe Operation

Every time a reference is taken prior to the sterilization cycle, the monitor checks itself to ensure that these photometric properties have not varied from factory specifications. Each instrument contains a validation filter, made of a polymeric material chosen because of its insensitivity to moisture and temperature conditions. The filter also has unique spectral characteristics at the wavelengths used to measure hydrogen peroxide and water. The spectrum of H₂O₂ and H₂O do not change. Every time the monitor is instructed to take a reference, the validation filter is temporarily moved into the light path and the optical characteristics of the analyzer are checked. If the monitor fails any of the diagnostic checks, or does not meet factory specifications, it will give an error message and will not allow itself to continue. This same filter is available as a manual probe insert, testing the external (fibers and probe) components of the system, providing data via the RS232 port or touchscreen.

H₂O₂ vapor measurement range	0.1 - 50.0 mg/l [71.2 – 35,600 ppm V/V]
H₂O₂ measurement accuracy	± 0.1 mg/l
H₂O vapor measurement range	1.0 mg/l – to condensation [>1345 ppm V/V]
H₂O measurement accuracy*	± 0.2 mg/l
Wavelength accuracy	±1.0 nm
Bandwidth	6.0 ± 1.0 nm

*relative to concentration at the time of measurement

Operating Environment

Ambient temperature 10 – 35 °C
Optimal ambient temperature stability < ±2 °C
Relative humidity 0 – 95% non-condensing

Monitor Dimensions

Height: 29.2 cm (11.5”)
Width: 50.8 cm (20.0”)
Depth: 33.5 cm (13.2”)
Weight: 12 kg (25 lb)

Probe Specifications

32.0 cm length (12.6”) x 4.7 cm diameter (1.85”)
25.0 cm pathlength
Temperature and pressure range: 0 °C to 90 °C and suitable for use in 10-3 Torr
Fabricated parts are electropolished 316SS

Fiber Cable

6 m fiber length of Ultra Low -OH fiber with SS SMA connector on probe end and FC connector on monitor end
PVC jacketed fiber cable

Electrical and Communications Connections

Analog outputs: (37 pin D type) separate 0-l0 Vdc outputs for H2O2 and H2O: paralleled with a corre¬sponding 4-20 mA current signal
Serial input/output: RS232, 9 pin male; transmitting H2O2 and H2O concentrations, date, time, and serial number

Included as Standard

Monitor
Probe
Terminated fiber cable pair, each 6 meters long
Power cord
Communications cable (9 pin female to 9 pin female)
Extra tungsten halogen bulb - 6 watts
Fuses and SMA wrench
Complete operations manual
Power Supply: universal switching, 50/60 Hz, 120 or 220 Vac

Options

Additional terminated fiber cable, 6 meters long
Additional probes, custom probes
External validation filter
50 cm single sided G-SST probe
Custom length fiber cable (max 20 meter distance, probe to monitor)
Annual factory calibration service

User Programmable Features

Password protection: 2 level, Operator and Administrator
Sampling time: 10 - 30 seconds
Reporting units: mg/l or ppm
Control source: built in keypad or RS232 communications port
Analog output scaling: 0 – 10 volts

Specifications are subject to change without notice.

Product Brochure

Technical Paper