MSA ORION User manual

FIRE AND RESCUE NSW
RECOMMENDED PRACTICE
FOUR-HEAD GAS DETECTOR
MSA ORION
VERSION 02, ISSUED: FEBRUARY 2011, CID: 06553

© State of New South Wales through Fire and Rescue NSW, 2011.
This work may be freely reproduced and distributed for most purposes, however some restrictions apply. See the
General Copyright Notice on www.fire.nsw.gov.au or contact Fire and Rescue NSW (FRNSW).
This Recommended Practice contains information, data, documents, pages and images prepared by FRNSW for
training, occupational health and safety, and reference purposes. The material it contains may be incomplete,
inaccurate, or out of date. The State of NSW accepts no responsibility or liability in relation to the use of any
information contained in this document.
Published by:
Specialised Operations
Fire and Rescue NSW
Amarina Avenue
(Locked Bag 13)
Greenacre NSW 2190
Telephone: [phone]
Facsimile: [phone]
Document Control:
Ve r s i o n A , J a n 2 0 0 5
Version 02, February 2011. (Comprehensive review, update contact details, revisions to troubleshooting and risk
management.)
Supply Catalogue CID:
06553
Acknowledgements:
Mine Safety Appliance Company
Senior Firefighter Daren Ellen
Station Officer Stuart Harvey
Station Officer Timothy Climo
Senior Firefighter Matt Dahlberg
Senior Firefighter Glenn Jackson
Senior Firefighter Andrew Johnson
Senior Firefighter Richard Neville
Filing:
NFB/08514
Working file located at Equipment Development Unit, Greenacre (filed by CI number)
This document rescinds:
Operations Bulletin 2008/07: Orion gas detector extension probe, Ver 01.
Recommended practice: Orion four-head gas detector, Ver A.
Has this document been printed or copied?
Check you have the most recent version by comparing the version number and the issue date on the footer with
those of the document on station portal on the Intranet. The online document is the master.
This document was produced using Adobe Framemaker™ version 8.0. It is intended for release as an electronic
PDF document for online viewing. It is formatted for double-sided printing on station printers. Copies are
available through the Electronic Supply Catalogue.

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CONTENTS
Using this Document v
Warnings, Cautions and Notes v
Electronic navigation v
Document control vi
Specific Equipment Warnings vii
Section 1 Introduction 1
1.1 Manual structure 1
1.2 General 1
1.3 Limitations 2
1.3.1 Intrinsic safety 3
1.4 Reading 3
1.5 Contact 3
Section 2 Equipment Fact Sheet 4
2.1 Kit contents 4
2.2 Main features 5
2.3 Control layout 6
2.3.1 The LCDs 6
2.3.2 Control buttons 8
2.4 Specifications 9
2.4.1 Calibration / challenge test gas specification 9
2.4.2 Orion specifications 9
2.4.3 Sensor specifications 10
2.5 Principles of operation 11
2.5.1 The Orion 11
2.5.2 Principles of calibration 11
2.5.3 Explosive limits 11
Section 3 Operations 12
3.1 Safety 12
3.1.1 Risk management 12
3.1.2 Protective clothing 13
3.2 Navigating LCD pages 14
3.3 Before operations 15
3.3.1 Assembling the wand 15
3.3.2 Turning on and pre-operational checks 16
3.3.3 Zero the Orion 17
3.3.4 Challenge test 18
3.3.5 Field calibration 20
3.3.6 Clearing peaks 21
3.3.7 Clearing STEL and TWA 22
3.3.8 Test the pump 23

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3.4 Operations 24
3.4.1 Operational hints 24
3.4.2 Heartbeat indicator 24
3.4.3 Alarms – general 24
3.4.4 Gas concentration alarms 25
3.4.5 Battery condition and alarm 26
3.4.6 Datalogging 27
3.5 Turning Off 27
Section 4 Maintenance 28
4.1 Maintenance schedule 28
4.2 After use 29
4.3 Changing batteries 29
4.4 Changing filters 31
4.4.1 External water stop 31
4.4.2 Dust filter 31
4.4.3 Internal water stop 32
4.5 Changing time and date 32
4.6 Downloading data 33
4.7 Troubleshooting 33
4.8 Resupply 34
4.8.1 Calibration gas 34
4.8.2 Other consumables 34
Appendix A Principles of Gas Detection 35
A.1 Short Term Exposure Limit 35
A.2 Time Weighted Average 36
A.3 Combustible gas sensor 36
A.4 Oxygen and toxic gas sensors 37
A.5 Orion sensor configuration 38
A.6 Orion LEL correlation factors 38
A.7 Cross sensitivity 40
A.8 Temperature class 40
Glossary 41
References 43
Index 44

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USING THIS DOCUMENT
Warnings, Cautions and Notes
Throughout this manual, the reader will find statements titled: WA R N I NG,
CAUTION or NOTE. These consist of a short piece of information highlighting a
hazard or providing additional clarification, or both. Each of these statements has a
particular meaning, as follows:
WARNING
PERSONAL INJURY MAY RESULT if warnings are not carefully
heeded. Warnings give you precautions for avoiding injury. While the
emphasis of warnings is on avoiding injury, the situations described
may also involve damage to equipment.
CAUTION
EQUIPMENT MAY BE DAMAGED if these recommended
procedures are not carefully followed. Cautions tell you what to do
to avoid such damage. Personal injury is not expected.
NOTE
OPERATIONAL PROCEDURES are clarified. Neither personal
injury nor equipment damage is involved.
Electronic navigation
This document has been produced in PDF format. The electronic document has a
number of features which aid navigation.
• In the left frame of the
Acrobat Reader window are
bookmarks which replicate
the contents page. Click the
bookmark to go to that
heading.
• To expand a bookmark to a
list of subheadings, click the
‘ ’ beside the bookmark.
• In the body of the document
you will find cross references.
For instance: See ‘Electronic
navigation’, highlighted in
blue. Your cursor icon will change to a pointing finger when over a link. Click
these to go to the referenced section, table or figure.
Figure: Selecting bookmarks
+

vi Four-Head Gas Detector: MSA Orion
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•Thecontentspagehaslivelinks to the referenced pages. Your cursor icon will
change to a pointing finger when over a link. Click the heading to go to that
page.
•Theindexisarrangedalphabetically and has live links to the source text. Your
cursor icon will change to a pointing finger when over a link. Click the page
number to go to the text.
• To return to either the index or contents page, click any other bookmark, and
then click the index or contents bookmark.
Document control
This Recommended Practice is a Fire and Rescue NSW managed document. This
document will become uncontrolled if printed, saved, copied or emailed.
Wherever possible, users should refer to the Fire and Rescue NSW Intranet: Station
Portal for Recommended Practices.
NOTE
If this document has been printed, copied or emailed, check the
validity by confirming the version number and the issue date in the
footer with the those of the document on Station Portal on the
Intranet. Station Portal will always display the most recently
approved document.

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SPECIFIC EQUIPMENT WARNINGS
This is a summary of important warnings and cautions regarding the
Orion four-head detector. It is not an exhaustive list of all the warnings
and cautions you will find as you read the recommended practice.
WARNING
Always wear breathing apparatus (BA) when there is any
possibility of a hazardous atmosphere.
WARNING
The Orion must only be used by personnel trained in its operation.
WARNING
Before use:
•zerotheOrion
• conduct challenge test
• clear peaks, TWA and STEL
• test the pump.
WARNING
The Orion can only detect and measure:
• combustible gases and certain combustible vapours
• oxygen concentration
• carbon monoxide
• hydrogen sulphide.
Do not attempt to measure other gases with the Orion.
WARNING
Changing batteries is not intrinsically safe. Do not change
batteries in a potentially flammable atmosphere.

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SECTION 1: INTRODUCTION
1.1 Manual structure
This manual consists of five sections:
Section 1: Introduction
Section 2: Equipment Fact Sheet
Section 3: Operations
Section 4: Maintenance
Appendix: Principles of Gas Detection
Index
1.2 General
This Recommended Practice instructs firefighters in the use of the Mine Safety
Appliances Company Orion four-head gas detector (Orion). For how you will use
the Orion at an incident, refer to your training material.
Figure 1 The Orion four-head gas detector
Sampling wandSampling hose
Orion, in
protective
rubber boot
Carry strap Attached
quick start
instructions

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WARNING
The Orion must only be used by people trained in its operation.
The Orion has a simple, two button operation. It is powered by three AA alkaline
cells. It features an automatic datalogging facility. The Orion uses four sensors to
detect:
• oxygen (O2) percentage in the atmosphere
• carbon monoxide (CO), in parts per million
• hydrogen sulphide (H2S), in parts per million
•combustiblegasesandsomecombustiblevapours as a percentage of the Lower
Explosive Limit (LEL).
The Orion continuously monitors these four conditions. The instrument alarms
when any one condition reaches preset alarm levels. These levels are given in Table
6: Gas concentration alarms, on page 25.
In addition, the oxygen concentration shown by the Orion can be used as an
indicator of other contaminants. See Section 3.4.1: ‘Operational hints’ on page 24
for more information.
Use the Orion when your dynamic risk assessment indicates one of the above
hazardous atmospheres might exist and that atmospheric monitoring is a suitable
control measure. Atmospheric monitoring is mandatory in confined spaces.This
monitoring helps determine:
• the hot zone boundary
•safeOHSlimitsfortheuseofrespiratory and personal protective equipment for
these hazards
• render safe.
Consider adequate fire protection.
If a toxic gas alarms sounds, notify the Incident Controller (IC) and continue
monitoring.
When operating in an ambient temperature above 40 oC and your 10% LEL alarm
sounds, stop your activity and reassess your dynamic risk assessment and incident
action plan. If required, exit and/or seek specialist advice from HMRU on the nature
of the contaminant.
When operating at any ambient temperature in an environment which may contain
carbon disulphide, exit the area if the 10% LEL alarm sounds.
See A.8: ‘Temperature class’, on page 40, for temperature classes of gases.
1.3 Limitations
The Orion indicates the presence of, but does not identify, combustible gases.
The Orion does not measure the toxicity of combustible gases.
Response time is 30 to 45 seconds.

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If the atmosphere is rich or deficient in oxygen, the Orion’s combustible and toxic
gas readings can be affected.
High humidity can lessen oxygen readings over time.
The Orion should not be used to monitor:
• reducing atmospheres, such as ammonia,
• atmospheres containing combustible mists or airborne dusts.
A high sample temperature, such as when a sample is drawn from inside a furnace
stack, will affect the readings. This is not recommended.
Battery consumption is high when the unit alarms, for instance during the challenge
test. Acknowledge alarms quickly and keep spare batteries on hand.
1.3.1 Intrinsic safety
The Orion meets:
• AS/NZS 60079.11:2000 for intrinsic safety, within the temperature limits of
–20 °C to 40 °C
• AS/NZS 61779.1:2000 for intrinsic safety
• AS/NZS 61779.1:2000 and 61779.4:2000 for performance of electrical
apparatus for the detection and measurement of flammable gases in
environments with a potentially explosive atmosphere, other than mines where
high over-range %LEL readings can occur.
See Section 2.4: ‘Specifications’ on page 9 for details of intrinsic safety.
1.4 Reading
This Recommended Practice must be read in conjunction with the following
documents:
1.5 Contact
Any queries regarding the equipment or procedures described in this document
should be directed to Gas Help on 0407 663491.
• Standard Operating Guidelines, Section 9: Respiratory protection, Fire and
Rescue NSW, Greenacre, Australia.
• Hazardous Materials SOG 10.1: Guidelines for all hazardous materials
incidents, Fire and Rescue NSW, Greenacre, Australia.
•Firefighters Training Manual Vol 2, ‘Topic Six: Breathing Apparatus’, Fire
and Rescue NSW, Greenacre, Australia.
•Recommended practice: Wearing of uniforms and personal protective
equipment (PPE), CI:06745, Fire and Rescue NSW, Greenacre, Australia.

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SECTION 2: EQUIPMENT FACT SHEET
2.1 Kit contents
Figure 2 Orion kit contents
Table 1: Orion kit contents
Item
1Hose for connecting to regulator and calibration gas (black).
2Sampling hose, with wand connection and water stop filter
3Calibration/challenge test gas.
4
Tool kit with:
• calibration nozzle
•3xsparewaterstopfilters
• spare internal dust filters
• 3 x spare batteries (Duracell MN1500 available through ESCAT, CI:00017) as well as
the three in the Orion.
• screw driver with Phillips head and two sizes of Allen key
•quickreferencecard.
5Regulator for calibration gas.
6Orion, with rubber boot, carry strap and quick start guide.
7Sampling wand.
Recommended practice (not shown).
1
2
3
5
4
6
7

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2.2 Main features
Figure 3 Orion gas detector main features
Table 2: Orion main features
Part Explanation
1Alarm lights Flash red during alarm conditions.
2Pump cap The pump cap covers the sensors.
3LCD This section of the LCD displays date, time, battery charge,
and alarm indicators.
4LCD This section of the LCD displays gas concentrations.
5 On/Off/Page button Power on and off, and scroll through displays.
6Gas inlet/probe
connection
For connection of the sampling probe and calibration nozzle
for calibration/challenge gas.
7Gas outlet Gas outlets are located in both sides of the pump cap.
8Inlet filters Dust filter and internal water stop.
9Change/Resetbutton To change values, and acknowledge alarm conditions.
10 Speaker Issues audible alarms.
11 Battery pack screws Remove to change batteries.
12 Unit ID Fire and Rescue NSW identification chip.
13 Battery pack For 3 x alkaline batteries.
14 Belt clip For attaching to belt, if required.
3
4
12
9
5
8
6
11
14
10
13
1
7
2

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2.3 Control layout
2.3.1 The LCDs
The layout of the Orion liquid crystal display (LCD) flags is given below.
Table 3: LCD flag explanation
Flag Explanation
Zero Zero flashes at start-up or during calibration, giving the option to zero the
instrument.
Cal Cal shows when the calibration option is selected, and flashes when calibration
can be initiated.
Time Time shows, and the current time is displayed in a 24 hour format on the main
LCD.
MM, DD, YY MM, DD, YY show, and the current date is displayed in the US format on the main
LCD.
Change Change shows when it is possible to change values. To accept a value, press
On/Off/Page.
Pump Pump flashes when the gas sampling circuit is blocked. The unit goes into pump
alarm.
Peak
Peak shows. Peak readings are displayed in the relevant locations of the main
LCD. These are the highest gas concentrations recorded by each of the four
sensors since the instrument was last turned on or peaks were cleared.
Min Min shows, and the minimum O2value recorded since the instrument was last
turned on or reset is displayed in the O2section of the main LCD.
STEL
Shows the current Short Term Exposure Limit for the CO and the H2S sensors, as
calculated by the Orion from instant readings. The STEL flag comes on, and the
values appear in the relevant parts of the LCD. See A.1: ‘Short Term Exposure
Limit’, on page 35 for an explanation of STEL.
TWA
Shows the current Time Weighted Average for the CO and the H2S sensors, as
calculated by the Orion from instant readings. The TWA flag comes on, and the
values appear in the relevant parts of the LCD. See A.2: ‘Time Weighted
Average’, on page 36 for an explanation of TWA.
Please wait until the Orion is ready.
Battery indicator: Displays continuously. Segments disappear with battery use.
The indicator shows battery time remaining.
Display
during
start-up

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Figure 4 The Orion LCD showing the instant reading display in clean air
The battery flag displays at all times. Instant readings for %LEL, %O2, ppm CO,
and ppm H2S are displayed.
Heartbeat. This flag flashes every 30 seconds to the left of the battery detector to
confirm the instrument is on and operating.
%LEL The instant reading for combustible gases is shown here. Peak value is displayed
here when that option is chosen.
%O2
The instant reading for oxygen is shown here. Peak and Min values are displayed
here when those options are chosen.
PPM CO The instant reading for carbon monoxide is shown here. Peak, STEL, and TWA
values are also displayed here when those options are chosen.
PPM H2SThe instant reading for hydrogen sulphide is shown here. Peak, STEL, and TWA
values are also displayed here when those options are chosen.
Table 3: LCD flag explanation
Flag Explanation
Display
during
start-up

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2.3.2 Control buttons
The Orion is operated by two buttons:
• On/Off/Page
•Change/Reset.
On later models, the words on the On/Off/Page and Change/Reset buttons have
been replaced by symbols. See Figure 5: ‘The control buttons’ for details. The
function of the buttons is unchanged.
Either button can be:
•pressedandreleased(press)
• pressed and held for three to five seconds (press and hold).
Figure 5 The control buttons
Using the On/Off/Page button:
•PressOn/Off/Page to turn the unit on.
• Once on, press On/Off/Page to scroll through instrument displays.
• When the Change flag shows, press On/Off/Page to accept the change
• In the Calibration menu press On/Off/Page to initiate zeroing or calibration.
• Press and hold On/Off/Page for five seconds to turn the unit off.
Using the Change/Reset button:
•PressChange/Reset to acknowledge alarm conditions.
• Press and hold Change/Reset for three seconds to initiate a change of values.
• Press and hold Change/Reset for three seconds to enter Calibration menu.
•PressChange/Reset to refuse options given by the Orion.
At all times, leaving the control buttons returns the Orion to instant reading mode.
Old style New style

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2.4 Specifications
2.4.1 Calibration / challenge test gas specification
2.4.2 Orion specifications
Combustible gas: 58% LEL (1.45% by volume methane, to simulate the pentane
reading)
Oxygen: 15%
Carbon Monoxide: 300 ppm
Hydrogen Sulfide: 10 ppm
Dimensions (wand removed): 10.2 x 6.8 x 17.3 cm
Dimensions carry case: 15.5 x 48.5 x 37.5 cm
Weight (with wand and hose): 1 kg
Weight whole kit: 4.0 kg approx
Temperature range: 0 to 40 °C (when calibrated at room temp)
Extended temperature range: –20 to 50 °C (when calibrated at temperature of use)
Warm-up time: 25 seconds
Battery: 3 x AA (LR6) alkaline cells. Use only Duracell
MN1500 Available on ESCAT, CI:00017), or
Energizer E91
Battery duration: 10 hours (non-alarming)
Regulator flow rate: 0.25 litres per minute
Protection rating: IP54
Intrinsic safety: Ex ia s Zone 0 1/IIC T4, –20 ºC < Ta < 40 ºC
This means the Orion is safe in environments,
including underground, with atmospheres of < 20.8%
oxygen and:
• Ambient temperatures between –20 ºC and 40 ºC.
• Explosive concentrations of any gas having an
ignition point above 135 ºC.
• Non-explosive concentrations of gas and/or dust.
•Explosiveconcentrationsof methane and coal dust
continuously present.
• Explosive concentrations of gas groups IIA, IIB
and IIC continuously present.
For ambient temperatures between 40 ºC and 50 ºC,
the Orion is rated at T3, and is safe in an explosive
concentration of any gas having an ignition point
above 200 ºC.

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2.4.3 Sensor specifications
The following table gives the specifications for the Orion sensors, given normal
operating temperatures and sampling hose of 3 metres.
WARNING
If the start-up challenge test gives a result outside ± 10% of the
challenge gas specifications, the unit must be calibrated before use.
NOTE
Oxygen response time is up to 3 minutes if the Orion is calibrated
outside the normal temperature range.
Table 4: Sensor specifications
Oxygen – O2Combustible Toxic – CO Toxic – H2S
Sensor type Electrochemical Catalytic Electrochemical Electrochemical
Response
time
(with hose)
90% of final
reading in 35 – 40
seconds
90% of final
reading in 35 – 40
seconds
90% of final
reading in 35 – 40
seconds
90% of final
reading in 40 – 45
seconds
Range O2as 0% to 25%
of atmosphere 0% to 100% LEL 0 – 999 ppm 0 – 200 ppm
Resolution 0.1% 1% LEL 1 ppm 1 ppm
Accuracy ±10% of the reading – only applicable when the challenge test has been passed and
within specified operating temperatures

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2.5 Principles of operation
2.5.1 The Orion
A pump draws the gas sample into the instrument through a sampling wand. Filters
remove water and dust particles. A set of four sensors then test the gas for
combustibles, oxygen content, carbon monoxide and hydrogen sulphide.
NOTE
If necessary, the Orion can be used without the wand and sampling
hose.
Combustible gases are tested by a catalytic sensor. See A.3: ‘Combustible gas
sensor’, on page 36 for details.
Oxygen and toxic gases are measured by electrochemical sensors. See A.4:
‘Oxygen and toxic gas sensors’, on page 37 for details.
The Orion is protected by a series of three filters:
• a water stop filter in the wand,
• a dust filter located on the rear of the Orion,
• an internal water stop located in the body of the Orion under the dust filter.
2.5.2 Principles of calibration
Calibrating the Orion involves these concepts:
a) The instrument is first zeroed. This means that the response of the instrument in
clean air is registered.
b) Calibration gas of a known concentration is applied to the instrument. The
response to this known concentration is registered.
c) The difference between the zero gas response and the known concentration
response is the span. Instrument readings for concentrations from zero to this
known concentration are set according to this span.
An unknown concentration of a gas is determined by comparing the response of the
instrument to the unknown, with the span value.
2.5.3 Explosive limits
To sustain combustion, there must be an appropriate mix of fuel (in this case a
flammable gas) and oxygen. If the mix is too lean and there isn’t enough fuel, the
reaction can’t sustain itself. If the mix is too rich and the fuel starts to displace the
oxygen, the reaction will once again stop.
The Lower Explosive Limit (LEL) is the lowest percentage of fuel in the mix for
combustion to take place.
The Upper Explosive Limit (UEL) is the highest percentage of fuel in the mix for
combustion to take place.

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SECTION 3: OPERATIONS
3.1 Safety
WARNING
At all times, observe the following safety precautions when operating
the Orion multi-gas detector.
3.1.1 Risk management
Use the Orion when your dynamic risk assessment indicates one of the following
hazardous atmospheres might exist and that atmospheric monitoring is a suitable
control measure:
• oxygen enriched or deficient atmospheres
• presence of CO and/or H2S
• the explosive hazard presented by combustible gases.
In addition, the oxygen concentration shown by the Orion can be used as an
indicator of other contaminants. See Section 3.4.1: ‘Operational hints’ on page 24
for more information.
This monitoring helps determine:
• the hot zone
• safe OHS limits for the use of personal protective equipment for these hazards
• render safe.
Atmospheric monitoring is mandatory in confined spaces.
The Orion must only be operated by personnel trained in its use.
WARNING
The Orion does not measure the toxicity of combustible gases.
Always be aware of the toxic hazard as well as combustibility. Always
wear BA when conducting atmospheric monitoring.
Only monitor gases for which sensors have been fitted. Do not
attempt to monitor other gases.
Consider adequate fire protection.
If a toxic gas alarms sounds, notify the Incident Controller (IC) and continue
monitoring.
When operating in an ambient temperature above 40 oC and your 10% LEL alarm
sounds, stop your activity and reassess your dynamic risk assessment and incident
action plan. If required, exit and/or seek specialist advice from HMRU on the nature
of the contaminant.
When operating at any ambient temperature in an environment which may contain
carbon disulphide, exit the area if the 10% LEL alarm sounds.
See A.8: ‘Temperature class’, on page 40, for temperature classes of gases.