Overview of ChemDAQ Peracetic Acid Monitor

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The ChemDAQ gas monitoring system is designed for occupational safety. The system consists of ChemDAQ’s Steri-Trac gas monitors that provide continuous real time readings of the gas or vapor and user settable instantaneous alarms.

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2. Page 2 of 5 SM-103-A-0.00 ChemDAQ Inc. • 300 Busi ness Center Drive • Pittsburgh, PA • 15205 phone 412.787.0202 • fax 412.788.2526 Specifications of DAQ Computer DAQ® operating system Windows 7 Software ChemDAQ Inc Proprietary Monitors per DAQ 1 to 32 Gas types per DAQ Single or multi-type gas monitors Backwards compatible to PointGard II Yes 15 min STEL (OSHA EL) & 8 Hr TWA (OSHA PELs) Yes Impending alarms Yes Data Storage Yes Data Export & Interface Export: CSV fi le; Interface: SQL database, optional Modbus available Automatic data back-up in removable storage Yes Monitor DAQ/PC Communications Digital RS 485, Optional Steri-Tr ac over Internet available Reporting capability Graphs and Reports Monitor configuration Available through DAQ, external PC or monitor DAQ visual indicator of alarms Green OK, yellow impending alarm, red alarm The ChemDAQ gas monitoring syst em is modular so that it can be tailored to each customer’s needs; and is made up of Ster i-Trac gas monitors, the DAQ computer, remote displays and other ancillary equipment. The remote displays mirrors the monitor display and horn alarm status and are used to warn approaching people of a gas or vapor leak before they enter the area.

3. Page 3 of 5 SM-103-A-0.00 ChemDAQ Inc. • 300 Busi ness Center Drive • Pittsburgh, PA • 15205 phone 412.787.0202 • fax 412.788.2526 Recommended Alarm Levels The following values are the recommended alarm limits for the ChemDAQ peracetic acid monitor. These alarm limits are user adjustable. Instantaneous Alarms at the Monitor Low Alarm: 0.75 ppm High Alarm: 1.5 ppm Time Weighted Average Alarms at the DAQ STEL Alarm: 0.4 ppm 8 Hr TWA 0.2 ppm Monitor : The monitor connects to the sensor module and displays the current gas concentration. It also has two instantaneous alarms, high and low. Under normal conditions, the display is green, turns yellow for low alarm and red for hi gh alarm. A horn sounds an alert if the low or high alarms are reached. The monitors also contains two relays, each triggered by the alarm level, that can be used to interf ace with air handlers, strobes etc. The monitor can operate as a stand-alone instrument or it can be connected to the DAQ computer. Monitors are currently available for per acetic acid, hydrogen per oxide, ethylene oxide, ozone, oxygen and combustible (LEL). The latte r two are primarily used in commercial applications. Each monitor is configured for a specific gas, but can be factory reconfigured for a different gas. Specifications for Steri-Trac Monitor Dimensions 10” x 6” x 5” Display Tri-Color, 4 digit, 1.25”, 5x8 Matrix LED. Automatic restart on power restoration Yes Sensor-module battery life > 2 weeks Mounting Wall mounted Remote sensor available Yes Power supply 90-260 VAC, 50/60 Hz, at 1 amp External contact relays 2

1. Page 1 of 5 SM-103-A-0.00 ChemDAQ Inc. • 300 Busi ness Center Drive • Pittsburgh, PA • 15205 phone 412.787.0202 • fax 412.788.2526 Overview of ChemDAQ’s Peracetic Acid Monitor Richard Warburton March 2014 Need for Peracetic Acid Continuous Monitoring ............................................................... 1 Overview ChemDAQ ® Steri-Trac System ......................................................................... 1 Specifications of DAQ Computer ................................................................................... 2 Recommended Alarm Levels.............................................................................................. 3 Monitor ........................................................................................................................ ....... 3 Specifications for Steri-Trac Monitor ............................................................................. 3 Peracetic Acid Sensor Module............................................................................................ 4 Specifications for Peracetic Acid Sensor Module .......................................................... 4 Sensor Calibration (SXP) ® ................................................................................................. 4 Calibration Gas ............................................................................................................... 5 Accuracy of the Steri-Trac Gas Monitor ............................................................................ 5 Cross Sensitivity and Bump Testing................................................................................... 5 Need for Peracetic Acid Continuous Monitoring Peracetic acid is finding wide spread use in healthcare and food processing including endoscope reprocessing to peracetic acid inte rventions in meat and poultry. Peracetic acid is a strong oxidant and broad spectrum bioc ide that quickly decomposes to harmless byproducts, (oxygen, water and acetic acid) thus delivering pathogen free products with no harmful residues. Until recently employe rs did not know what concentration of peracetic acid constituted a safe exposure, but with the recently issued (spring 2014) ACGIH TLV STEL for peracetic acid of 0.4 ppm (discussed above), and with the ChemDAQ peracetic acid continuous gas monito r, employers can now ensure that their people are safe. Overview ChemDAQ ® Steri-Trac System The ChemDAQ gas monitoring system is desi gned for occupational safety. The system consists of ChemDAQ’s Ster i-Trac gas monitors that provide continuous real time readings of the gas or vapor and user settable instantaneous alarms. Up to 32 monitors of any combination of gas types, can be conn ected to a DAQ® computer which logs the data, calculates time weighted average (TWA) exposures and activates TWA alarms, provides reports and graphing and provides an interface to building control systems via an SQL data base or ‘485 module. [Note the individual monitors also have relays that trigger at the alarm thresholds for external in terfacing] The data can also be exported as a .CSV file for analysis in Excel or any other spread sheet etc.

4. Page 4 of 5 SM-103-A-0.00 ChemDAQ Inc. • 300 Busi ness Center Drive • Pittsburgh, PA • 15205 phone 412.787.0202 • fax 412.788.2526 Relay options Both normally open/closed available Alarms High & low, user settable Alarm options Acknowledge and latch, user settable Approvals UL, CSA & CE; IS Sensor Module available for EtO, O 2 & LEL Peracetic Acid Sensor Module The sensor module contains the gas sensor, circuitry to suppo rt it, chemical filters (if applicable) and an internal battery to enab le fast start-up when the sensor module is initially installed. The sensor module plugs into the monitor and passes the current gas readings to the monitor. The sensor module connects directly on to the monitor or via a remote sensor mount. Specifications for Peracetic Acid Sensor Module Sensor Three electrode amperometric sensor Sensor Module Communications Digital, RS 485 Hot swap sensor module Yes Range 0 to 6 ppm Digital Resolution 0.01 ppm Minimum Detection Limit (MDL) 0.04 ppm Temperature Range -20 to + 50 oC Response Time (T 90 ) < 30 s Response Linear Spot-On ® filter Yes, for hydrogen peroxide Accuracy The greater of the MDL or 5% of reading, relative to the calibration gas. Calibration Interval 4 months Sensor Calibration (SXP) ® : The ChemDAQ sensor modules, like all gas sens ors, require periodic calibration as a basic function check of operation and to ensu re that the output matches the actual gas concentration. Field calibration is often problematic, especially with reactive gases such as peracetic acid. Instead ChemDAQ provide s a calibration servi ce for all users of ChemDAQ equipment. ChemDAQ tracks the date since the last calib ration, contacts the customer and sends factory calibrated sensor s. The customer swaps the sensors (very simple), and returns the old sensors to Chem DAQ; where the chemical filters are replaced

5. Page 5 of 5 SM-103-A-0.00 ChemDAQ Inc. • 300 Busi ness Center Drive • Pittsburgh, PA • 15205 phone 412.787.0202 • fax 412.788.2526 (peracetic acid and ethylene oxide), the batteries recharged and the sensors recalibrated. All calibrations ar e performed using the target gas. Calibration Gas The ChemDAQ peracetic acid sensor is calib rated with peracetic acid test gas. The peracetic acid test gas used for calibration is generated in -house using a proprietary method and the generator runs co ntinuously at constant temper ature to ensure steady state conditions. The test gas is titrated weekly and verified again before each calibration. The titration was validated by parallel analysis using an optical method. Accuracy of the Steri-Trac Gas Monitor An electrochemical sensor provides a linear output proportional to th e gas concentration, the proportionality factor being determined by the calibration. Like any electrochemical sensor there is some intrinsi c variation with temperature, but the sensor module includes automatic temperature compensation. The sens or output is linear ove r the range and the repeatability is good (typically 0.02 ppm). Th e overall accuracy of the monitor is the greater of 5% or the minimum detection limit of 0.04 ppm relative to the calibration gas. The accuracy of the calibration gas is also about 5%. Thus the overall accuracy of the sensor as shipped is better than the greater of the MDL or 10% of reading. Cross Sensitivity and Bump Testing The bare peracetic acid sensor does have so me cross sensitivity to hydrogen peroxide, which is often present in si gnificant amounts with peracetic acid. The peracetic acid sensor module includes a proprieta ry chemical filter that allo ws peracetic acid to pass but removes essentially all of the hydrogen peroxide (> 98%). This filter is replaced each time the sensor is returned to ChemDAQ for calibration. The peracetic acid sensor also has some cross sensitivity to nitrogen dioxide (NO 2 ), with a cross sensitivity factor of 1.3:1, i.e. 1 ppm of nitrogen dioxide will give a reading equivalent to 1.3 ppm of perace tic acid. This cross sensitivit y may be used as a bump test to verify the operation of the monitors in th e field between calibrations. Users can obtain the 1- 3 ppm nitrogen dioxide from their lo cal specialty gas supplie r and apply it at 0.5 lpm to the sensor module. ChemDAQ also offers a peracetic acid bump te st kit which contains a pre-measured vial of water that is mixed with a chemical powde r to produce peracetic ac id vapor. Neither of these methods are sufficiently accurate for ca libration and are simply offered to allow users to verify that there peracetic acid monitors are functioning correctly.

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