3M GMI PS200 Series Manual

64171, Rev. 10/May 2019
WARNING: ALL INDIVIDUALS WHO HAVE OR WILL HAVE RESPONSIBILITY FOR
USING, MAINTAINING, OR SERVICING THIS PRODUCT MUST READ THIS
ENTIRE MANUAL CAREFULLY. FAILURE TO USE THIS EQUIPMENT
PROPERLY COULD RESULT IN SERIOUS INJURY OR DEATH.
3M™ GMI™ PS200 PORTABLE GAS MONITOR
OPERATIONS & MAINTENANCE MANUAL 64171, Rev. 10

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
REVISION HISTORY
ii
Copyright © 3M™ GMI™, May 2019
The information contained within is for use only with the 3M™ GMI™ PS200 Portable Gas Moni-
tor. Reproduction, in whole or in part, including utilization in machines capable of reproduction or
retrieval without written permission of 3M™ GMI™ is prohibited.
REVISION HISTORY
Rev.
No. Revision Date Reason
10 May 2019 Reformatted and revised entire manual.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
DESCRIPTION
iii
DESCRIPTION
This Operations & Maintenance (O&M) Manual provides information for use only with the 3M™
GMI™ PS200 Portable Gas Monitor (or “the monitor”).
LIABILITY
Every care has been taken in the preparation of this O&M manual, but 3M™ and GMI™ do not
accept any responsibility for errors or omissions and their consequences. Information in this O&M
manual is subject to change without notice. This O&M manual does not constitute a specification or
basis for a contract.
MODIFICATION NOTICES
3M™ GMI™ aim to notify customers of relevant changes in the product operation and maintain this
O&M manual up to date. Due to continuous product improvement, there may be operational differ-
ences between the latest product and this O&M manual.
This O&M manual is an important part of the monitor, and it should be referred to for the life of the
product.
SOFTWARE
Any software supplied must only be used in this product and may not be copied without the written
permission of 3M™ GMI™. Reproduction or disassembly of such embodied programs or algorithms
is prohibited. Ownership of such software is not transferable, and 3M™ GMI™ does not warrant that
the operation of the software will be error free or that the software will meet the customer’s require-
ments.
DISPOSAL ADVICE
Dispose of the monitor carefully and with respect for the environment. 3M™ GMI™ will dispose of
the monitor without charge if the monitor is returned to 3M™ GMI™.
AREAS OF USE
Exposure to certain chemicals can result in a loss of sensitivity of the flammable sensor. Where such
environments are known or suspected it is recommended that more frequent response checks are
carried out. Chemical compounds that can cause loss of sensitivity include silicones, lead, halogens
and sulphur.
Do not use the monitor in potentially hazardous atmospheres containing greater than 21% oxygen.
SPECIAL CONDITIONS OF USE
The monitor is designed for use in harsh environments. The monitor is sealed to IP67 and, if not sub-
jected to misuse or malicious damage, will provide many years of reliable service.
The monitor may contain electrochemical sensors. Under conditions of prolonged storage, these
sensors should be removed. These sensors contain potentially corrosive liquid and care should be
taken when handling or disposing, particularly when a leak is suspected.
WARRANTY
The monitor has a standard warranty of 2 years against faulty mechanical and electronic parts, e.g.
pump, sensors, battery, flexi-PCB etc, provided that any servicing has been carried out by the manu-
facturer or authorized agent. The warranty does not include filters or damage caused by misuse (e.g.
mechanical impact or water ingress). For further details, please contact 3M™ GMI™.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
iv
This page is intentionally left blank.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
TABLE OF CONTENTS
v
TABLE OF CONTENTS
Sect. # Section Title Page #
1. ABOUT THIS GUIDE............................................................................................................................ 1-1
1.1. Guide Conventions ........................................................................................................................... 1-1
1.2. Certifications and Approvals.........................................................................................................1-2
1.3. General Safety Information........................................................................................................... 1-4
1.4. Additional Safety Details - CSA ONLY ..................................................................................... 1-4
2. INTRODUCTION...................................................................................................................................2-1
2.1. General Description..........................................................................................................................2-1
2.2. Features...............................................................................................................................................2-3
2.3. Datalogging........................................................................................................................................2-3
2.4. Filters....................................................................................................................................................2-3
3. OPERATION.......................................................................................................................................... 3-1
3.1. Operating Procedure....................................................................................................................... 3-1
3.2. Quick Configuration Display ........................................................................................................3-2
3.3. Switching the Monitor On.............................................................................................................3-2
3.4. Switch the Display Backlight On/Off ........................................................................................3-7
3.5. View MAX/MIN/STEL/LTEL........................................................................................................3-7
3.6. Manual Datalog................................................................................................................................ 3-8
3.7. Alarms Reset or Acknowledge.................................................................................................... 3-8
3.8. Sample Line Connection and Use.............................................................................................. 3-8
3.9. Self Test.............................................................................................................................................. 3-9
3.10 Switch the monitor OFF...............................................................................................................3-10
4. ALARMS................................................................................................................................................. 4-1
4.1. Gas Alarms ......................................................................................................................................... 4-1
4.2. Acknowledge Gas Alarms.............................................................................................................4-2
4.3. Mute Alarms ......................................................................................................................................4-2
4.4. High Flammable Gas Over-range Alarm ..................................................................................4-2
5. WARNINGS & FAULTS ..................................................................................................................... 5-1
5.1. Low Battery ........................................................................................................................................ 5-1
5.2. Bat Fault............................................................................................................................................... 5-1
5.3. Zero Fault............................................................................................................................................ 5-1
5.4. Sensor Faults..................................................................................................................................... 5-3
5.5. Flow Fault (Pumped Monitors Only)......................................................................................... 5-3
5.6. Memory Fault ................................................................................................................................... 5-4
5.7. Calibration Required ...................................................................................................................... 5-4
6. MANUAL BUMP TEST OPTIONS .................................................................................................. 6-1
6.1. Bump Testing..................................................................................................................................... 6-1
6.2. Initiating a Manual Bump Test ..................................................................................................... 6-1
6.3. Applying Test Gas ...........................................................................................................................6-3

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
TABLE OF CONTENTS
vi
Sect. # Section Title Page #
6.4. Quick/Full Bump Test ....................................................................................................................6-3
6.5. Confirm Alarms ................................................................................................................................6-4
7. RECHARGING THE BATTERIES .....................................................................................................7-1
7.1. General................................................................................................................................................. 7-1
7.2. Recharge Monitor Using the Charging/Comms Clip ........................................................... 7-1
8. OPERATOR MAINTENANCE ..........................................................................................................8-1
8.1. Cleaning...............................................................................................................................................8-1
8.2. Replace Filters ...................................................................................................................................8-1
9. CALIBRATION.......................................................................................................................................9-1
9.1. General Description.........................................................................................................................9-1
9.2. Quick Calibration.............................................................................................................................9-2
9.4. Calibration Validity..........................................................................................................................9-4
10. ACCESSORIES*..................................................................................................................................10-1
A. OPERATING PARAMETERS & SENSOR TYPES....................................................................... A-1
A.1. Typical Operating Parameters..................................................................................................... A-1
A.2. LEL Sensor Types.............................................................................................................................A-2
B. TECHNICAL SUPPORT......................................................................................................................B-1

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
LIST OF FIGURES
vii
LIST OF FIGURES
Fig. # Figure Title Page #
2-1 PS200 Portable Gas Detector ......................................................................................................2-1
2-2 Display Example (4-Gas) ...............................................................................................................2-2
2-3 Display Examples .............................................................................................................................2-2
2-4 OK Display Example (4-Gas)........................................................................................................2-2
3-1 Function Buttons .............................................................................................................................. 3-1
3-2 Quick Configuration Display ........................................................................................................3-2
3-3 Flash Screen...................................................................................................................................... 3-3
3-4 Monitor Identification Display .................................................................................................... 3-3
3-5 User Name......................................................................................................................................... 3-3
3-6 Date and Time .................................................................................................................................. 3-4
3-7 Bump Due Date................................................................................................................................ 3-4
3-8 Bump Overdue ................................................................................................................................. 3-4
3-9 Calibration Due Date...................................................................................................................... 3-5
3-10 Service Due Date............................................................................................................................. 3-5
3-11 Cal Gas Selection ............................................................................................................................ 3-6
3-12 Sensor Check Displays.................................................................................................................. 3-6
3-13 4-Gas Normal Operating Display ...............................................................................................3-7
3-14 MAX/MIN/STEL/LTEL Gas Values............................................................................................3-7
3-15 Manual Datalog................................................................................................................................ 3-8
3-16 Sample Line Connection............................................................................................................... 3-9
3-17 Pump Symbol ................................................................................................................................... 3-9
3-18 Self Test.............................................................................................................................................3-10
3-19 Switch OFF.......................................................................................................................................3-10
4-1 O2 LOLO Alarm................................................................................................................................. 4-1
4-2 LEL HIHI Alarm .................................................................................................................................4-2
4-3 Over Range Alarm........................................................................................................................... 4-3
4-4 GET OUT/HIGH GAS Timer........................................................................................................ 4-3
5-1 LOW BATTERY Warning ............................................................................................................... 5-1
5-2 BAT FAULT Warning....................................................................................................................... 5-1
5-3 LEL ZERO Fail....................................................................................................................................5-2
5-4 LEL ZERO FAULT .............................................................................................................................5-2
5-5 ZERO FAULT – Switch OFF .........................................................................................................5-2
5-6 LEL SENSOR FAULT ...................................................................................................................... 5-3
5-7 CO/H2S SENSOR FAULT............................................................................................................. 5-3
5-8 FLOW FAULT ................................................................................................................................... 5-4
5-9 Memory Fault ................................................................................................................................... 5-4
5-10 Calibration Overdue....................................................................................................................... 5-4
5-11 CAL EXPIRED ................................................................................................................................... 5-5

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
LIST OF FIGURES
viii
Fig. # Figure Title Page #
5-12 Calibration Required.......................................................................................................................5-5
6-1 BUMP TEST Confirmation Screen ..............................................................................................6-1
6-2 Apply Gas Screen (4-Gas Model) ..............................................................................................6-2
6-3 Regulator Valve Choice.................................................................................................................6-2
6-4 Bump Test Kit....................................................................................................................................6-3
6-5 Confirm Alarms ................................................................................................................................6-4
6-6 Bump Test Pass ................................................................................................................................6-4
6-7 Confirm Alarms - Fail......................................................................................................................6-4
6-8 Bump Test Fail - Switch Monitor OFF ......................................................................................6-5
7-1 Charging/Comms Clip Connection............................................................................................7-1
7-2 Connect Cable to Charging/Comms Clip............................................................................... 7-2
7-3 Connect Cable to USB Power Adapter .................................................................................... 7-2
8-1 Hydrophobic Filter Replacement ................................................................................................8-1
8-2 Sample Inlet (Dust) Filter Replacement....................................................................................8-2
9-1 PS200 Auto/Bump Calibration Station.....................................................................................9-1
9-2 ZERO CALIBRATION Screen.......................................................................................................9-2
9-3 SPAN CALIBRATION Screen ......................................................................................................9-2
9-4 APPLY GAS Screen.........................................................................................................................9-3
9-5 APPLY GAS Screen.........................................................................................................................9-3
9-6 CAL COMPLETE/SAVE RESULTS Screen..............................................................................9-3

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
LIST OF TABLES
ix
LIST OF TABLES
Table # Table Title Page #
1-1 Certifications and Approvals.........................................................................................................1-2
10-1 Supplied Accessories.....................................................................................................................10-1
10-2 Optional Accessories.....................................................................................................................10-1
10-3 Charging Accessories....................................................................................................................10-1
10-4 Manual Bump & Field Calibration Kit .......................................................................................10-1
10-5 Automatic Bump & Calibration Accessory (ABC) ...............................................................10-2
A-1 Typical Operating Parameters.....................................................................................................A-1
A-2 LEL Sensor Types............................................................................................................................A-2

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
LIST OF TABLES
x
This page is intentionally left blank.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
ABOUT THIS GUIDE
1-1
1. ABOUT THIS GUIDE
This guide instructs gas detection personnel on the features and usage of the PS200 Portable Gas
Monitor (or “the monitor”), including information on operation, configuration, maintenance, specifi-
cations and troubleshooting.
This user guide assumes the reader has a basic knowledge of gas detection procedures.
The user guide is divided into the following topics:
•2. INTRODUCTION
•3. OPERATION
•4. ALARMS
•5. WARNINGS & FAULTS
•6. MANUAL BUMP TEST OPTIONS
•7. RECHARGING THE BATTERIES
•8. OPERATOR MAINTENANCE
•9. CALIBRATION
•10. ACCESSORIES*
•APPENDIX A. OPERATING PARAMETERS & SENSOR TYPES
•APPENDIX B. TECHNICAL SUPPORT
1.1. Guide Conventions
The following visual elements are used throughout this guide, where applicable:
WARNING: THIS ICON AND TEXT INDICATE A POTENTIALLY HAZARDOUS
SITUATION, WHICH, IF NOT AVOIDED, COULD RESULT IN DEATH OR
INJURY.
CAUTION: This icon and text indicate an action or situation, which, if not avoided, could
result in damage to the equipment.
NOTE: This icon and text designates information of special note.
WARNING: READ, UNDERSTAND AND FOLLOW THE ENTIRE CONTENT OF THIS
GUIDE PRIOR TO USE. FAILURE TO DO SO MAY RESULT IN SERIOUS
INJURY OR DEATH.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
ABOUT THIS GUIDE
1-2
1.2. Certifications and Approvals
The monitor has the following approvals available:
Table 1-1: Certifications and Approvals
Mark
ATEX II 2G Ex ia d IIC T4 Gb (Ta = -20ºC to +50ºC)
IECEx Ex ia d IIC T4 Gb (Ta = -20ºC to +50ºC) or
ATEX II 1G Ex ia IIC T4 Ga (Ta = -20ºC to +50ºC)
IECEx Ex ia IIC T4 Ga (Ta = -20ºC to +50ºC)
(when fitted with the SGX VQ548MP sensor)
Combustible Instruments:
Class I, Div.1 Groups A, B, C and D T4
Class I, Zone 1 AEx ia d IIC T4 Gb Ex ia d IIC T4 Gb
or
Class I, Div.1 Groups C and D T4
Class I, Zone 0 AEx ia IIB T4 Ga Ex ia IIB T4 Ga
(when fitted with the SGX VQ548MP sensor)
Non-combustible Instruments:
Class I, Div.1 Groups A, B, C and D T4
Class I, Zone 0 AEx ia IIC T4 Ga Ex ia IIC T4 Ga
MED (Marine Equipment Directive) - A.1 / 3.30 (Module B&E)
European Mark of Conformity
ATENÇÃO: NÃO RECARREGAR
EM AREA CLASSIFICADA
DNV 16.0082 XU
14-AV4BO-0010
Ex ia d IIC T4 Gb (Ta = -20ºC to +50ºC)
IECEx SIR11.0019

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
ABOUT THIS GUIDE
1-3
1.2.1. LABEL
Always refer to the rear label for the actual certification of your monitor (see Figure 1-1: Identification
Label).
Figure 1-1: Identification Label
The label also lists the monitor’s serial number, e.g. 241000.
1.2.2. PERFORMANCE
This monitor complies with:
EN60079-29-1 (Flammable)*
IEC60079-29-1 (Flammable)*
EN50104:2010 (Oxygen)** – Marine instruments.
ANSI / ISA S12.13.01 – 2000 (Combustible)*
C22.2 No.152 – M1984 (Combustible)*.
* excludes IR sensor option.
** 2yr O2 sensor only
TP TC 012/2011
TP TC 020/2
Table 1-1: Certifications and Approvals
Mark

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
ABOUT THIS GUIDE
1-4
1.3. General Safety Information
3M™ GMI™ can take no responsibility for use of its equipment if it is not used in accordance with
these instructions. If further operational or maintenance details are required but not provided in this
guide, contact 3M™ GMI™ or their agent. 3M™ GMI™ shall not be liable for any incidental or conse-
quential damages in connection with any modifications, errors or omissions in this guide.
Always observe the latest pertinent state, regional, and local safety regulations when using and dis-
posing of the monitor. For reasons of safety and to assure regulatory compliance, only the manufac-
turer should perform repairs.
Fully trained personnel must regularly service and calibrate the monitor in a safe area.
Only use 3M™ GMI™ replacement parts.
Re-charge the monitor only in a safe area (refer to Section 7. RECHARGING THE BATTERIES).
If the monitor detects gas, follow your organization’s procedures and operational guidelines.
Any right of claim relating to product liability or consequential damage to any third party against
3M™ GMI™ is removed if the above warnings are not observed.
1.4. Additional Safety Details - CSA ONLY
WARNING: ALL INDIVIDUALS WHO HAVE OR WILL HAVE RESPONSIBILITY FOR
USING OR TESTING THIS PRODUCT MUST READ AND UNDERSTAND
THE CONTENTS OF THIS MANUAL. THE PRODUCT WILL PERFORM AS
DESIGNED ONLY IF USED AND TESTED IN ACCORDANCE WITH THE
MANUFACTURER'S INSTRUCTIONS. FAILURE TO FOLLOW
MANUFACTURER'S INSTRUCTIONS WILL RENDER THE WARRANTY AND
APPROVALS NULL AND VOID. FAILURE TO FOLLOW THESE
INSTRUCTIONS MAY ALSO RESULT IN SERIOUS INJURY OR DEATH.
CAUTION: BEFORE EACH DAYS USAGE, TEST ON A KNOWN CONCENTRATION OF
METHANE, EQUIVALENT TO 25% – 50% OF FULL-SCALE
CONCENTRATION. ACCURACY MUST BE WITHIN 0 TO +20% OF
ACTUAL. ACCURACY MAY BE CORRECTED BY CALIBRATION (REFER TO
Section 9. CALIBRATION.
ATTENTION: AVANT CHAQUE UTILISATION JOURNALIÈRE, TESTEZ LA RÉACTION
DE L’APPAREIL EN UTILISANT UNE CONCENTRATION CONNUE EN
MÉTHANE, CORRESPONDANT À 25% – 50% DE LA VALEUR RÉELLE. LA
PRÉCISION DOIT SE SITUER ENTRE 0 ET + 20% DE LA VALEUR RÉELLE.
LA PRÉCISION PEUT SE CORRIGER EN ÉTALONNANT L’APPAREIL
(VOIR Section 9. CALIBRATION).
CAUTION: ANY RAPID UP-SCALE READINGS FOLLOWED BY A DECLINING OR
ERRATIC READING MAY INDICATE A GAS CONCENTRATION BEYOND
THE UPPER SCALE LIMIT, WHICH MAY BE HAZARDOUS.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
ABOUT THIS GUIDE
1-5
ATTENTION: TOUT LECTURE DÈPASSANT RAPIDEMENT LE MAXIMUM DE
L’ÊCHELLE ET SUIVIE PAR UNE DIMINUTION OU UNE LECTURE
ERRONÉE, INDIQUE UNE CONCETRATION DE GAZ SUPÉRIEURE À LA
VALEUR MAXIMALE DE CETTE ÉCHELLE. CETTE LECTURE N’EST
PASSIGNIFICATIVE.
CAUTION: SUBSTITUTION OF COMPONENTS MAY IMPAIR INTRINSIC SAFETY.
ATTENTION: LE REPLACEMENT D’UN COMPOSANT PEUT PORTER ATTEINT À LA
SÉCURITÉ INTRINSÈQUE DE PRODUIT.
CAUTION: DO NOT CHARGE IN A HAZARDOUS AREA. Um = 6V.
ATTENTION: NE PAS CHARGER EN ZONE DANGEREUSE. UM = 6V.
NOTE: CSA have only assessed the LEL combustible gas detection portion of this monitor
for performance.
NOTE: CSA a seulement évalué la partie LIE pour la mesure des performances en détection
de gaz inflammables.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
ABOUT THIS GUIDE
1-6
This page is intentionally left blank.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
INTRODUCTION
2-1
2. INTRODUCTION
2.1. General Description
3M GMI PS200 Portable Gas Monitor series combines quality, ruggedness and advanced technol-
ogy in a user friendly, portable gas detector. It is compact, lightweight, water resistant, extremely
robust, and is suitably certified to recognized International Standards.
The monitor is suitable for wide range of personal monitoring and confined space applications. If gas
levels exceed configured threshold limits, or if the monitor develops a fault, users will be alerted by
audible, visible, and vibratory alarms.
The monitor is available as either a pumped or diffusion model and is powered by a fast-charging
internal Li-ion (lithium ion) battery.
The monitor is simple to use and is operated via two buttons (refer to Figure 2-1: PS200 Portable Gas
Detector).
Figure 2-1: PS200 Portable Gas Detector
The monitor can detect up to 4 of the following gases simultaneously:
• LEL Hydrocarbons
• Oxygen (O2)
• Carbon Monoxide (CO)
• Hydrogen Sulphide (H2S)

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
INTRODUCTION
2-2
All gases being monitored are displayed. A 4-gas monitor display is illustrated in Figure 2-2: Display
Example (4-Gas).
Figure 2-2: Display Example (4-Gas)
Figure 2-3: Display Examples
Instead of displaying current gas readings, the monitor can be configured to display OK, as illustrated
in Figure 2-4: OK Display Example (4-Gas).
Figure 2-4: OK Display Example (4-Gas)
NOTE: Character size increases if fewer sensors are configured, as illustrated in Figure 2-3:
Display Examples.
NOTE: This manual describes the operation of a default 4-gas monitor. Configurable
options are available and are detailed in italic text, where applicable.

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
INTRODUCTION
2-3
2.2. Features
• Compact, lightweight and robust.
• Measurement and display of up to 4 gases.
• Simple 2 button operation.
• Audible, visual (hi-viz) flashing LED’s and vibrating alarms.
• Audible and visual confidence signal (configurable), confirming monitor operation to the user.
• Green display during normal operation and red during alarm condition.
• Internal pump (optional).
• Manual and automatic data logging.
• Internal Li-Ion (Lithium Ion) rechargeable battery.
• Maximum recharge time of 4 hours.
• Robust clip to allow fitting to belt, pocket, etc.
• Communications interface to allow downloading of stored data.
• Fully certified to international standards.
• Comprehensive range of accessories .
• Quick Configuration Display allows the configuration to be viewed without fully switching the
monitor ON.
Typical operating parameters are detailed in Section APPENDIX A. OPERATING PARAMETERS & SEN-
SOR TYPES of this manual.
2.3. Datalogging
Datalogging allows gas measurements, event logs, bump tests, and calibration details to be stored
for downloading to a PC/Laptop via a USB connection. Typically, the monitor can store up to 6
months of data (refer to Section APPENDIX A. OPERATING PARAMETERS & SENSOR TYPES).
2.3.1. Accessing Logged Data
Download data from the monitor to a PC/Laptop using the standard charging/comms cable and
additional software. Contact the 3M GMI Sales Department for further details.
2.4. Filters
Filters protect the monitor from water and dust ingress. Check filters regularly and replace as neces-
sary (refer to Section 8.2. Replace Filters).

64171, Rev. 10/May 2019
3M™ GMI™ PS200 PORTABLE GAS MONITOR
INTRODUCTION
2-4
This page is intentionally left blank.