Haz Mat Monitoring And You!!!

HazMat Monitoring and You!!!
…or what they taught you in HM
School but you already forgot!!!

Your Instructor…
Professor Russell Peterson
MS, HM Specialist
Honorary Associate Professor of Hazmatology and
Applied Chemically Contaminated Atmospheric
Sampling Sciences

What we will learn today:

• Understand the operations of the various
types of monitors the BFD uses;
• Understand and demonstrate the usage of
these monitors;
• Understand the limitations of these
monitors; and
• Understand and demonstrate the
calibration of these monitors.

Types of monitors

• Lower Explosive Limits (flammable
gases)
• Oxidizers
• Toxic gases (CO, H2S, Cl2, NH3, etc.)
• Radiation
• Hazardous Chemicals

Two sources of monitoring
• Point source
– This is taken at the source of the contaminant or
material – used for determining presence of HM.
– Contaminant is drawn into the monitor via an air
pump – representative of the atmosphere at the end
of the probe.
• Ambient
– This is taken at the monitor face and is more
representative of the total atmosphere – used for
responder safety (“breathing zone”).
– Is gas dependent. Some gases sink or rise so
ambient monitoring is not as effective as point source
monitoring.

Lower Explosive Limit monitors

• Measures the concentration of a
flammable vapor or gas in air indicating
the results as a percentage of the LEL of
the calibration gas
• Instruments use a combustion chamber
containing a filament that combusts the
flammable gas

LEL, continued…

• Filament is coated with a catalyst to
facilitate combustion
• The filament is part of a balanced resistor
circuit called a “Wheatstone Bridge”
• The filament burns the gas which increase
the temperature of the filament
• As filament temperature rises, so does
resistance

LEL, continued…

• This increased resistance results in an imbalance
in the Wheatstone circuit and is reflected by a
digital or analog readout on the meter.
• Organic lead vapors (leaded gasoline) foul the
filament and acid gases will cause the filament
to corrode.
• Instrument is temperature dependent, as are
most flammable gases.

Relative Response

• The different types of instruments that we use
are calibrated to specific flammable gases
• When you are “measuring” gases other than the
calibration gas, the instrument will read either
higher or lower depending on the material
• Spilled gasoline in a sewer system that contains
methane can be a problem
• BE CAREFUL!!!

Cross Sensitivity Multipliers
for the CMX and TMX monitors
• Hydrogen 0.5 • Methanol 0.6
• Methane 0.7 • Ethanol 0.8
• Acetylene 0.7 • Acetone 0.9
• Ethylene 0.6 • Isopropanol 1.1
• Ethane 0.7 • Benzene 0.9
• Propane 0.8 • Toluene 1.0
• Butane 0.8 • Styrene 1.5
• Pentane 1.0 • Xylene 1.3
• Hexane 1.3
Subject to an accuracy of +/- 25%
per manufacturer

Rule of thumb
The lighter the material (or the fewer carbons
it has), the less the multiplier. The number
on your LEL meter will be greater than the
percentage of actual LEL you have present…

Oxidizer monitors

• These monitors are used to monitor the
atmosphere for four reasons:
– Oxygen content for respiratory purposes – below
19.5%, atmosphere is oxygen deficient
– Increased risk of combustion – above 25%,
atmosphere is oxygen enriched
– Use of other instruments. Below 10% affects LEL
monitors
– Presence of contaminants. Many other chemicals will
displace oxygen. Each % decrease on the monitor
means a 5% drop in oxygen and a 5% increase in
“something else”

Oxidizer monitors, continued

• Caveat – an “oxygen” monitor measures
all oxidizers, from O2 to O3 (ozone) to off
gassing nitrates, chlorates (Cl2 and O2
radicals), and perchlorates. Don’t get in
the habit of thinking that the number you
are reading is the oxygen percentage; it is
the percentage of an oxidizer which is in
the atmosphere.


• Monitor uses a electrochemical sensor that
measures oxidizer concentration in the air.
• Sensor is made on two electrodes, a housing
containing a basic electrolyte solution, and a
semi-permeable Teflon membrane.
• Atmosphere enters the membrane, reacts with
the solution which results in produces an
electrical current.
• This current is passed through an amplifier
which is reflected on a digital or analog meter.


• Process is non-reversible and is a chemical
reaction (rxn). Whenever it is removed
from a nitrogen purged atmosphere, it is
active. Sensor life span is about 1 year.
• Exposure to CO2 and strong oxidizing
chemicals (such as chlorine and ozone)
will cause the sensor to wear out quicker.

Effects of Oxygen levels

• +23% Extreme fire hazard
• 21% Normal air concentration
• 19.5% Minimum OSHA safe level
• 16% Disorientation, impaired
judgement and breathing
• 14% Faulty judgement, fatigue
• 8% Mental failure, fainting
• 6% Difficult breathing, death in mins

Toxic gases monitors

• Used to:
– identify airborne chemicals,
– evaluate exposures to occupants and
responders,
– evaluate the need for PPE, and
– develop control methods to reduce exposure.

Toxic gases monitors

• Four kinds of Toxic Gas monitors
– Colorimetric inidicators
• Can be tubes, tape, or badges
– Specific chemical sensors
• Electrochemical sensors
– Total vapor survey meters
• PID’s and FID’s
– Gas Chromatographs

Toxic gases monitors, continued

• Colorimetric tubes
– Works through a chemical rxn which results in
a color change when the reagent is exposed
to a specific chemical.
– Amount of color change correlates to a
concentration that is drawn through the tube.
This concentration is correlated to a
percentage or ppm via the number of pump
strokes.

• Specific chemical sensors
– Monitor uses a electrochemical sensor that measures
oxidizer concentration in the air.
– Sensor is made on two electrodes, a housing
containing a basic electrolyte solution, and a semi-
permeable Teflon membrane.
– Atmosphere enters the membrane, reacts with the
solution which results in produces an electrical
current.
– This current is passed through an amplifier which is
reflected on a digital or analog meter.
– Sensor is non-reversible – is used up as long as it is
exposed to the gas


• Specific chemical sensors
– Metal Oxide sensor
• Consists of a metal oxide film coating on heated
ceramic substrate fused or wrapped around a
platinum wire coil
• Gas comes in contact with metal oxide, replaces
the oxygen in the oxide which results in a change
in conductivity
• Change in conductivity is reflected in a change in
the analog or digital meter
• Sensors are not always chemical specific. CO
sensors, for example, can rx with H2S gas

Effects of Carbon Monoxide

• 35 ppm PEL, 8 hrs (OSHA)
• 200 ppm frontal headache in 2-3 hrs
• 400 ppm frontal headache and nausea in
1-2 hrs; Occipital in 2.5-3.5 hrs
• 800 ppm Headache, nausea in 45 mins
• 6400 ppm Headache, nausea in 1 min
• 12,800 ppm Unconscious immediately; death
in 1-3 mins


• Total vapor survey meters
– PID’s (Photo Ionization Detector)
• Uses an ionizer (UV in the case
of the PID) to ionize the chemical
• The ionized chemical flows to the +
and – charged plates
• The mass of each ionized element is
measured
• The chemical reforms and exits through the pump
• Not chemical specific


• Total vapor survey meters
– FID’s (Flame Ionization Detector)
• Uses an ionizer (CH3 in the case of the FID) to
ionize the chemical
• The ionized chemical flows to the +
and – charged plates
• The mass of each ionized element is
measured
• The chemical is destroyed during the process
• Not chemical specific – specific for HC’s (must be
able to burn)


• Gas Chromatography

Radiation

• Radiation detectors
measure alpha, beta,
gamma, and neutron
radiation.
• Detection of radiation
can provide you with
info on exposure rates
and dose

Alpha Radiation

• Alpha is positively charged particles
consisting of two protons and two
neutrons. They are very heavy and have
low penetrating power.

Beta Radiation

• Beta is produced when an electron is emitted
from the nucleus of a radioactive atom, along
with an unusual particle called an antineutrino.
The neutrino is an almost massless particle that
carries away some of the energy from the decay
process. Because this electron is from the
nucleus of the atom, it is called a beta particle to
distinguish it from the electrons which orbit the
atom.

Gamma Radiation

• Gamma is a ray made up of high energy
photons of electromagnetic radiation. It
has no mass and is highly penetrating.

Radiation, continued

• Gamma is a ray made up of high energy
photons of electromagnetic radiation. It
has no mass and is high penetrating.

Gas Filled Radiation Detectors

• The most common type of instrument is a gas
filled radiation detector.
• Works on the principle that as radiation passes
through air or a specific gas, ionization of the
molecules in the air occur.
• A high voltage is placed between two areas of
the gas filled space, the positive ions will be
attracted to the negative side of the detector
(the cathode) and the free electrons will travel
to the positive side (the anode).

Gas Filled Radiation Detectors

• Charges are collected by the anode and cathode
which then form a very small current. This small
current is measured and displayed as a signal on
the meter.
• The two most common are the ion chamber
used for measuring large amounts of radiation
and the Geiger-Muller or GM detector used to
measure very small amounts of radiation.

Scintillation Radiation Detector

• The second most common type of radiation
• Uses a special material which glows or
“scintillates” when radiation interacts with it.
• The most common type of material is a type of
salt called sodium-iodide.
• As electron enter the front, they strike a
photocathode which produces more electrons.
These electrons are multiplied until they strike
an anode at the rear of the detector which
causes an energy pulse. This pulse is reflected
on the meter.

Hazardous Chemicals

• To identify unknown
chemicals, the HazCat
System is an effective
method. It provides for
immediate on-site ID &
characterization of
virtually any spilled
material.

Hazardous Chemicals

What is it???
Flammable?
Toxic?
Corrosive?
Reactive?

The different brands of monitors
and detectors that BFD uses are:
• Industrial Scientific CMX 271
• Industrial Scientific TMX 412
• BW Defender
• Ludlum Radiological Response Kit
• HazTech HazCat Kit

Operation and Maintenance of the
Industrial Scientific CMX 271
• Technical Specifications
– Sensor types
• CO – electrochemical
• LEL – catalytic, diffusion type
• O2 – electrochemical
– Battery life is 10 hours on full charge
– Temperature range is -15oC to +40oC
– Humidity range is 0-95% RH

CMX 271 TechSpecs

– Measuring range
• CO – 0 to 1999 PPM
• LEL – 0 to 99% LEL
• O2 – 0 to 30% vol
– Accuracy
• CO - +/- 5% of reading for 0 to 300 ppm; +/- 7.5% of
reading for 300 to 1999 ppm
• LEL – +/- 3% LEL for 0 to 30%; +/- 7.5% for 30 to 99%
• O2 - +/- 0.5% O2 for 10 to 30%; +/- 0.75% for 0 – 10%

Industrial Scientific TMX 412
Technical Specifications
– Sensor types
• H2S – electrochemical
– Temperature range is -4oF to +122oF

TMX 471 TechSpecs

– Measuring range
• CO – 0 to 999 PPM
• LEL – 0 to 100% LEL
• O2 – 0 to 30% vol
• H2S – 0-999 PPM

Industrial Scientific
CMX 271 and the TMX 412

• Turning the unit on
• Testing the sampling pump
• Calibrating the unit
• Turning the unit off

BW Defender
Technical Specifications
– Sensor types
– Temperature range is -20oC to +50oC

BW Defender TechSpecs

– Measuring range
• CO – 0 to 500 PPM
• LEL – 0 to 100% LEL
• O2 – 0 to 30% vol
• H2S – 0-100 PPM

BW Defender
• Testing the sampling pump

Ludlum Radiological Response Kit

• DISPLAY RANGE: Auto ranging from 0.0 microR/hr - 9999 R/hr;
0.000 microSv/hr - 9999 Sv/hr; 0 cpm - 999k cpm; or 0 cps - 100k
cps
• BATTERY LIFE: Typically 200 hours with alkaline batteries (low
battery indicated on display)
• CONSTRUCTION: Cast and drawn aluminum with beige
polyurethane enamel paint
• TEMPERATURE RANGE: -4° F(-20° C) to 122° F(50° C)
May be certified for operation from -40° F(-40° C) to 150° F(65° C)
• WEIGHT: 3.5 lbs (1.6kg) including batteries

Model 44-9 Pancake G-M Detector

• Used to frisk for alpha-beta-gamma

Model 44-2 Gamma Scintillator

• High energy gamma detection

Model 133-7 Energy Compensated
G-M
High range gamma measurements
Range is 25 mR/hr - 100 R/hr

Orientation to the
HazTech Systems HazCat Kit
• Reagents
• Associated Labware
• Safety concerns
– Chemicals
– Flammable gas
• Classification Process

Limitations of Detection Equipment

• Detection equipment is limited in the specificity
of materials that it detect.
• There are numerous environmental parameters
such as temperature, humidity, et cetera that
must exist for the detector to work properly.
• The detectors have an inherent error margin.
• The detector will not work properly if it is not
calibrated for the existing conditions.

Air Monitoring
Worksheet
Station 2
Instructions: Take a reading of the atmosphere at the opening of each can. Record your answers.
CMX 271 TMX 412 BW Defender
Source
Can A

Can B

Can C

Questions:
•Are the readings from all three instruments the same for each can and what do you think is in each can?
•List the possible reasons why the reading might differ.
•Why is 10% of the LEL used as an action level for atmospheric monitoring?

Practical Exercise

• Station 1 – Calibration station
• Station 2 – Liquid monitoring
• Station 3 – Atmospheric monitoring
• Station 4 – Gas monitoring
• Station 5 – Radiological monitoring

Station 1

• The purpose of this station is to practice
calibrating the different monitoring
instruments before usage.
• This will be a group activity!!!
• Pay attention…you might have to do this
sometime!!!

Station 2

• The purpose of this station is to determine
which liquid container is producing an
explosive or flammable vapor.
• DO NOT STICK THE PROBE INTO THE
LIQUID!!! And, yes, IT HAS BEEN DONE
BEFORE $!$!$!
• Record your answers on your work sheet.

Station 3

the effect distance has on an explosive
atmosphere.
• DO NOT STICK THE PROBE IN THE
LIQUID!!!
• Record your observations on the work
sheet.

Station 4

the concentration of explosive and/or toxic
gases within a closed environment.
• DO NOT INHALE THE GASES IN THE
BAGS!!!
• Record your answers on the work sheet.

Station 5

which material is radioactive.
• DO NOT GET THE MATERIAL ON YOUR
HANDS!!! WEAR GLOVES!!!
• Record your answers on the work sheet.

Haz Mat Monitoring And You!!!

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