•www.rkiinstruments.com
World Leader In Gas Detection and
Sensor Technology
•www.rkiinstruments.com
Company Background
• RKI founded in 1994• Partner company, Riken Keiki
o Leader In Gas Detection & Sensor Technology for over 73 years
• California Corporation• Average employee gas detection
experience is 15 years
75 Years of Milestones1938First
combustible interferometer
1969First
2 gas monitorLEL, O2, GX-3
1978First
3 gas monitorLEL, O2, COModel 1641
1980Pocket size single gas
OX/CO/HS-80
1982First belt
worn 3-gas, GX-82
1983Portable IR
for CO2RI-411
1986First
belt worn 4 gas monitor
GX-86
1990Portable
super toxicSC-90
1994Portable 4 gas
with datalogging & autocal
GX-94
1995First6 gas
portableEAGLE
1984Portable IR for Freons
RI-413
1997First wrist
wornGasWatch
75 Years of Milestones
20106 gas
portable with PID capabilityEAGLE 2
2009Smallest
confined space monitorGX-2009
2001Smallest
4 gasGX-2001
2003Smallesttri-modeportableGX-2003
Advanced tri-mode portable
Gas Tracer/GX-2012
2012 2013Remote Sample Pump
RP-2009
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Important Definitions
Flash Point Temperature at which the liquid phase gives off
enough vapor to flash when exposed to an external ignition source.
Fire Point When a liquid is heated past its flash point it will
reach a temperature where sufficient vapor is given off to maintain combustion.
Ignition Point The minimum temperature at which a substance
will burn or ignite independent of an external heat source.
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Reference Materials
NFPA Fire Protection Guide To Hazardous Materials Flash Point LEL/UEL Specific Gravity Vapor Density Hazard Identification
• Health/Flammability/Instability
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Reference Materials
NIOSH Pocket Guide To Chemical Hazards Chemical Name/Formulas Exposure limits (TWA) IDLH Physical Description Chemical and physical properties Incompatibilities and reactivities Health hazards
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Reference Materials
ACGIH, Threshold Limit Values for Chemical Substances and Physical Agents & Biological Exposure Indices Substance (CAS number) TWA STEL Molecular Weight TLV Basics-Critical Effects
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Flammability Band
Lean
0 100
Percent LEL
0 100Percent Gas by Volume
Ammonia 12.0 Vol. %Methane 5.0 Vol. %Hydrogen 4.0 Vol. %Hexane 1.1 Vol. %
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Explosive Rich
Lower Explosive Limit (LEL)
Upper Explosive Limit (UEL)
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Important Definitions
Lower Explosive Limit (LEL) Also known as Lower
Flammable Limit (LFL) Minimum concentration
of gas or vapor mixed with air that will cause the propagation of flame when it comes in contact with a source of ignition (spark or flame)
Concentrations of gas below the LEL are too lean to ignite
0%Vol 5%VolMethane (CH4)
0% LEL 100% LEL
LEAN
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Important Definitions
Upper Explosive Limit (UEL) Maximum
concentration of gas or vapor in air that will cause the propagation of flame when is exposed to a source of ignition (flame or spark).
Mixtures are considered to RICH to support combustion if they are above the UEL.
15%Vol 100%VolMethane (CH4)
RICH
UEL
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Explosive Range
• Explosive range is different depending on the gas or vapor
• As the fuel increases, oxygen decreases to the point where there is no longer a potential for explosion thus reaching the UEL
5%Vol 15%VolMethane (CH4)
EXPLOSIVE
LEL UEL
Intensity of Explosion
LOW LOW
HIGH
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More Flammability Bands
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Hexane Methane Hydrogen Carbon Monoxide Acetylene1.1-7.5% Vol 5.0-15% Vol 4.0-75% Vol 12.0-74% Vol 2.0-100% Vol
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Requirements for Combustion
IGNITIONSOURCE
FUELOXYGEN
World Leader In Gas Detection & Sensor Technology
Combustible Gas
Sensor Technology
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Constant Current Catalytic Bead
Active Reference
Platinum Alloy Wire
DeactivatorPlatinum Catalyst
Ceramic Coating
Four Wire Catalytic Bead Combustible Gas SensorConstant Current
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Constant Current Settings
Methane & Hexane Detection 148 mA
Hydrogen Calibration 130 mA
Hydrogen Specific Sensor 100 mA
Adjust current setting by placing an ammeter in series with the RED wire of the sensor.
Adjust current with pot at 12 O’clock position on amplifier as required
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Constant Voltage Catalytic Bead
Active Reference
Common
Platinum Alloy Wire
DeactivatorPlatinum Catalyst
Ceramic Coating
Constant Voltage Combustible Gas Sensor
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Catalytic Oxidation
CommonActive Reference
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Infrared (NDIR)
S
Light Source Measuring Cell Band Pass Filter
Infrared Sensor
Amplifier
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NDIR Troubleshooting
Contamination of the sensor will reduce energy reaching sensor causing high output Dust Moisture
Open source will cause output to peg upscale
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Metal Oxide Semiconductor
Non linear output Responds to many
different gases, non-specific
May respond to moisture
Broadband gas sensor
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MOS Troubleshooting
Contamination of oxide layer will cause unstable or erratic output
Improper heater voltage will cause sensor to function improperly
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Thermal Conductivity
Active Reference
Common
Reference element containedout of gas stream
Temperature coefficient of airis different than gas causingtemperature of coil to cool increasing resistance. Nocatalytic activity on sensor.
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TC Troubleshooting
TC sensors may open causing instrument to peg either upscale or downscale
Contamination can cause the sensor to respond improperly
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Hydrocarbon Comparison
Formula Name Ign Temp Deg. F Flash Point Deg. F LEL Vapor DensityCH4 Methane 999 Gas 5.0 0.60C2H6 Ethane 882 Gas 3.0 1.00C3H8 Propane 842 Gas 2.1 1.60C4H10 Butane 550 Gas 1.9 2.00C5H12 Pentane 500 <-40 1.5 2.50C6H14 Hexane 437 -7 1.1 3.00C7H16 Heptane 399 25 1.05 3.50C8H18 Octane 403 56 1.00 3.90C9H20 Nonane 401 88 0.80 4.40C10H22 Decane 410 115 0.80 4.90
World Leader In Gas Detection & Sensor Technology
Oxygen Detection
Sensor Operation and Theory
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Symptoms of O2 Deficiency
>23.5% OSHA limit for increased levels of oxygen
20.9% Oxygen content in normal air
19.5 - 12% Increased pulse and respiration
12 - 10% Disturbed respiration, fatigue, faulty judgment
10-6% Nausea, vomiting, inability to move, loss of consciousness
and death 6 - 0%
Convulsions, cardiac arrest and death
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Galvanic Oxygen Sensor
Typical output: 12-16 mV in fresh air
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Oxygen Sensor Troubleshooting
High or low output Unstable output Will not zero with N2
applied Leaking Sensor over 2 years
old (micro cells) Corroded or
contaminated Expired Sensor!
World Leader In Gas Detection & Sensor Technology
Electrochemical Toxic Gas Sensors
Sensor Operation and Theory
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Riken Electrochemical Sensors
Electrode material Bias voltage Electrolyte Reaction area of
electrode Electrolyte reaction
5 Key Factors that separate Riken sensors from the competition
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Riken Electrochemical Sensors
Long life (2+ years) Excellent stability High degree of
selectiveness Easy to replace and
calibrate
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Riken Electrochemical Sensors
Requires bias stabilization period
Replace if low span, over two years old, unstable output, slow response or recovery or if the sensor is leaking
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Electrochemical Sensors
Resistor
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Effects of Hydrogen Sulfide 0.01 - 10 ppm
Rotten egg smell 11 - 20 ppm
Rotten egg smell, irritation to eyes and throat 100 - 200 ppm
Loss of sense of smell in 2 - 5 minutes 250-400 PPM
Eye and throat irritation, loss of consciousness in 5-15 minutes
450-600 PPM Eye and throat irritation, respiratory distress,
unconscious in 1-15 minutes 650-900 PPM
Respiratory distress and unconsciousness in 1-3 minutes
950-1000 PPM Unconscious with one breath
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Effects of CO Exposure
25 PPM 8 hour time weighted average (ACGIH)
35 PPM 8 hour time weighted average (OSHA)
200 PPM Slight headache, discomfort within 3 hours
600 PPM Headache, discomfort within 1 hour
1000 - 2000 PPM Confusion, headache, nausea within 2 hours
2000 - 2500 PPM Unconsciousness within 30 minutes
4000 PPM Fatal in less than one hour
World Leader In Gas Detection & Sensor Technology
Hydrides
Sensor Operation and Theory
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Hydride Gases
Arsine…………….AsH3 Phosphine………..PH3 Silane…………….SiH4 Diborane…………B2H6 Germane…………GeH4
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Hydrolysis / Decomposition
Certain Mineral Acid Gases
When certain mineral acid gases (as used in the semiconductor industry) containing chlorinated and fluorinated compounds combine with water vapor or moisture in the ambient atmosphere, they decompose or hydrolyze to compounds, which includes either HCL or HF.
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HCLPhosphorus Oxychloride POCl3Antimony Pentachloride SbCl5Boron Trichloride BCl3Phosphorus Trichloride PCl3Silicon Tetrachloride SiCl4Tin Tetrachloride S4Cl4Titanium Tetrachloride TiCl4Dichlorisilane SiH2Cl2Trichlorosilane SiHCl3
HFArsenic Pentafluoride AsF5Phosphorous Pentafluoride PF5Boron Trifluoride BF3Phosphorous Trifluoride PF3Sulfur Tetrafluoride SF4Silicon Tetrafluoride SiF4Tungsten Hexafluoride WF6Tantalum Fluoride TaF5Titanium Fluoride TiF4Molybdenum Fluoride MoF4
Hydrolyzing Gases to HCL and HF
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List of Hydrolysis Gases
Gases that become HF after HydrolysisPhosphorus Pentafluoride PF5 PF3 + H2O = 2HF + POF3
(POF3 + 3H2O 3HF + H3 PO4)Boron Trichloride BF3 BF3 + 3H2O = 2HF + H3BO3
Silicon Tetrafluoride SiF4 2SiF4 + (X + 2) H2O = 2HF + H2SiF4, XH2O
Tungsten Hexafluoride WF6 WF6 + 3H2O = 6HF + WO3
Tantalum Fluoride TaF5 2TaF2 + 5H2O = 10HF + Ta2O5
Titanium Fluoride TiF4 TiF4 + 2H2O = 4HF + TiO2
Molybdenum Fluoride MoF4 MoF4 + 2H2O = 4HF + MoO2
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List of Hydrolysis Gases
Gases that become HCl after HydrolysisPhosphorus Oxychloride (POCl3) POCl3 + 3H2O = 3HCl + H3PO4
Antimony Pentachloride (SbCl5) SbCl5 + 10H2O = 10HCl + Sb2O5
Boron Trichloride (BCl3) BCl3 + 3H2O = 3HCl + H3BO3
Phosphorus Pentafluoride (PCl3) PCl3 + 3H2O = 3HCl + H3PO3
Silicon Tetrachloride (SiCl4) SiCl4 + 2 H2O = 4HCl + SiO2
Tin Tetrachloride (SnCl4) SnCl4 + 2H2O = 4HCl + SnO2
Titanium Tetrachloride (TiCl4) TiCl4 + 2H2O = 4HCl + TiO2
Dichlorosilane (SiH2Cl2) SiH2Cl2 + 4H2O = HCl + SiH2O2
Trichlorosilane (SiHCl3) SiHCl3 + 3H2O = 6HCl + (HSiO)2O
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List of Hydrolysis Gases
Other Hydrolysis Gases
Tetraethoxysilane (TEOS) Si(OC2H5)42Si(OC2H5)4 + 2H2O —> 8C2H5OH + 2SiO2 (ETHYLE)
Tetraethoxyarsine (TEOA) As(OC2H5)4 As (OC2H5)4 + 2H2O —> 4C2H5OH + AsO2 (ETHYLE)
Trimethoxyboron (TMB) B(OCH3)3 B(OCH3)3 + 3H2O —> 3CH3OH + H3BO3 (METHYLE)
Trimethoxyphosphate (TMP) P(OCH3)3 P(OCH3)3 + 3H2O—> H3PO4 + 3CH3OH (METHYLE)
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Understanding Date Codes
Each RKI Sensor has a date code to determine warranty begin date. The date code may be a small adhesive label on
the sensor or may be read from the serial number on the sensor.
Example: S/N 337096366AE• Date code is 33• First numeral is the year (2003)• Second numeral is the month (March)• Months are coded 1=Jan to 9= Sept. Oct.= X, Nov. = Y
and Dec. = Z.
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Questions?
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