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
•www.rkiinstruments.com
75 Years of Milestones
1938
1969
1978
1980
1982
1983
First
combustible
interferometer
First
2 gas monitor
LEL, O2, GX-3
First
3 gas monitor
LEL, O2, CO
Model 1641
Pocket size
single gas
OX/CO/HS80
First belt
worn
3-gas, GX-82
Portable IR
for CO2
RI-411
1984
1986
1990
1994
1995
1997
Portable IR
for Freons
RI-413
First
belt worn 4
gas monitor
GX-86
Portable
super toxic
SC-90
Portable 4 gas
with
datalogging
& autocal
GX-94
First
6 gas
portable
EAGLE
First wrist
worn
GasWatch
75 Years of Milestones
2001
2003
2009
2010
2012
Smallest
4 gas
GX-2001
Smallest
tri-mode
portable
GX-2003
Smallest
confined space
monitor
GX-2009
6 gas
portable
with PID
capability
EAGLE 2
Advanced trimode portable
Gas Tracer/
GX-2012
2013
Remote
Sample
Pump
RP-2009
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.
5
Reference Materials
 NFPA Fire Protection Guide To Hazardous
Materials





Flash Point
LEL/UEL
Specific Gravity
Vapor Density
Hazard Identification
• Health/Flammability/Instability
6
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
7
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
8
Flammability Band
Upper Explosive Limit (UEL)
Percent LEL
0 10
100
Lean
Explosive
0
Rich
Percent Gas by Volume
Ammonia
Methane
Hydrogen
Hexane
12.0
5.0
4.0
1.1
100
Vol. %
Vol. %
Vol. %
Vol. %
Lower Explosive Limit (LEL)
9
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% LEL
100% LEL
LEAN
0%Vol
5%Vol
Methane (CH4)
10
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.
UEL
RICH
100%Vol
15%Vol
Methane (CH4)
11
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
Intensity of Explosion
HIGH
LOW
LOW
LEL
UEL
EXPLOSIVE
15%Vol
5%Vol
Methane (CH4)
12
More Flammability Bands
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Hexane
1.1-7.5% Vol
Methane
5.0-15% Vol
Hydrogen
4.0-75% Vol
Carbon Monoxide
12.0-74% Vol
Acetylene
2.0-100% Vol
13
Requirements for Combustion
FUEL
OXYGEN
IGNITION
SOURCE
14
World Leader In Gas Detection & Sensor Technology
Combustible Gas
Sensor Technology
Constant Current Catalytic Bead
Platinum Catalyst
Deactivator
Platinum Alloy Wire
Ceramic Coating
Active
Reference
Four Wire Catalytic Bead Combustible Gas Sensor
Constant Current
16
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
17
Constant Voltage Catalytic Bead
Platinum Catalyst
Deactivator
Platinum Alloy Wire
Ceramic Coating
Active
Reference
Common
Constant Voltage Combustible Gas Sensor
18
Catalytic Oxidation
Active
Reference
Common
19
Infrared (NDIR)
Light Source
Measuring Cell
Band Pass Filter
Amplifier
S
Infrared Sensor
20
NDIR Troubleshooting
 Contamination of the sensor will reduce
energy reaching sensor causing high
output
 Dust
 Moisture
 Open source will cause output to peg
upscale
21
Metal Oxide Semiconductor
 Non linear output
 Responds to many
different gases, nonspecific
 May respond to
moisture
 Broadband gas
sensor
22
MOS Troubleshooting
 Contamination of
oxide layer will cause
unstable or erratic
output
 Improper heater
voltage will cause
sensor to function
improperly
23
Thermal Conductivity
Reference element contained
out of gas stream
Temperature coefficient of air
is different than gas causing
temperature of coil to cool
increasing resistance. No
catalytic activity on sensor.
Active
Reference
Common
24
TC Troubleshooting
 TC sensors may open
causing instrument to
peg either upscale or
downscale
 Contamination can
cause the sensor to
respond improperly
25
Hydrocarbon Comparison
Formula
CH4
C2H6
C3H8
C4H10
C5H12
C6H14
C7H16
C8H18
C9H20
C10H22
Name
Methane
Ethane
Propane
Butane
Pentane
Hexane
Heptane
Octane
Nonane
Decane
Ign Temp Deg. F Flash Point Deg. F
999
Gas
882
Gas
842
Gas
550
Gas
500
<-40
437
-7
399
25
403
56
401
88
410
115
LEL
5.0
3.0
2.1
1.9
1.5
1.1
1.05
1.00
0.80
0.80
Vapor Density
0.60
1.00
1.60
2.00
2.50
3.00
3.50
3.90
4.40
4.90
26
World Leader In Gas Detection & Sensor Technology
Oxygen Detection
Sensor Operation and Theory
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
28
Galvanic Oxygen Sensor
Typical output: 12-16 mV in fresh air
29
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!
30
World Leader In Gas Detection & Sensor Technology
Electrochemical
Toxic Gas Sensors
Sensor Operation and Theory
Riken Electrochemical Sensors
5 Key Factors that separate Riken sensors
from the competition




Electrode material
Bias voltage
Electrolyte
Reaction area of
electrode
 Electrolyte reaction
32
Riken Electrochemical Sensors
 Long life (2+ years)
 Excellent stability
 High degree of
selectiveness
 Easy to replace and
calibrate
33
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
34
Electrochemical Sensors
Resistor
35
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

450-600 PPM

650-900 PPM

950-1000 PPM
 Eye and throat irritation, loss of consciousness
in 5-15 minutes
 Eye and throat irritation, respiratory distress,
unconscious in 1-15 minutes
 Respiratory distress and unconsciousness in 13 minutes
 Unconscious with one breath
36
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
37
World Leader In Gas Detection & Sensor Technology
Hydrides
Sensor Operation and Theory
Hydride Gases





Arsine…………….AsH3
Phosphine………..PH3
Silane…………….SiH4
Diborane…………B2H6
Germane…………GeH4
39
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.
40
Hydrolyzing Gases to HCL and HF
HF
Arsenic Pentafluoride AsF5
Phosphorous Pentafluoride PF5
Boron Trifluoride BF3
Phosphorous Trifluoride PF3
Sulfur Tetrafluoride SF4
Silicon Tetrafluoride SiF4
Tungsten Hexafluoride WF6
Tantalum Fluoride TaF5
Titanium Fluoride TiF4
Molybdenum Fluoride MoF4
HCL
Phosphorus Oxychloride POCl3
Antimony Pentachloride SbCl5
Boron Trichloride BCl3
Phosphorus Trichloride PCl3
Silicon Tetrachloride SiCl4
Tin Tetrachloride S4Cl4
Titanium Tetrachloride TiCl4
Dichlorisilane SiH2Cl2
Trichlorosilane SiHCl3
41
List of Hydrolysis Gases
Gases that become HF after Hydrolysis
Phosphorus 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
42
List of Hydrolysis Gases
Gases that become HCl after Hydrolysis
Phosphorus 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
43
List of Hydrolysis Gases
Other Hydrolysis Gases
Tetraethoxysilane (TEOS)
Si(OC2H5)4
2Si(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)
44
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.
45
Questions?
46