chemical hazard is related to the chemicals that causing threat to people, animal and environment because of the exposure of same.

1. Hazard
A hazard is generally anything that
can hurt you or make you ill.

3. HAZARDOUS CHEMICAL
A material that has physical or chemical characteristic
of potential for causing harm
human injury,
damage to property,
damage to environment
or some combination of these is known as
hazardous chemical.

8. CHEMICAL HAZARD
• The undesired effects which are caused
with the absorption of hazardous
chemicals by the human body- are called
chemical hazards.
• The hazardous chemicals alone in
concentration, or when mixed with other
chemical substance, can cause injury,
disease or death.

9. TYPES OF CHEMICAL HAZARD
HEALTH HAZARD
PHYSICAL HAZARD

10. PHYSICAL HAZARD
• Flammable gases
• Flammable aerosols
• Oxidizing gases
• Gases under
pressure
• Flammable liquids
• Flammable solids
• Self-reactive
substances and mixtures
• Pyrophoric liquids
• contact with water,
emit flammable
gases
• Oxidizing liquids
• Oxidizing solids
• Organic peroxides
• Corrosive to metals
• Combustible dusts
• Pyrophoric gases

11. HEALTH HAZARD
• Acute toxicity
• Skin
corrosion/irritation
• Serious eye damage/eye
irritation
• Respiratory or skin
sensitization
• Germ cell
mutagenicity
• Carcinogenicity
• Reproductive toxicity
• Specific target organ
toxicity – single exposure
• Specific target organ
toxicity – repeated
exposure
• Aspiration hazard
• Bio hazardous infectious
materials

13. TYPES OF CHEMICAL HAZARD
• Naturally Occurring Chemicals
Ex. Mycrotoxin, Pyrrolizidine Alkaloides
• Intentionally Added Chemicals
Ex. Preservatives: Nitrite and Sulfiting agents.
• Unintentionally Or Incidentally Added
Chemicals
Ex. Pesticides, Lead, Arsenic, Mercury.

14. WHMIS
Workplace Hazardous Materials Information System
Goals-
 Prevent Health Hazards
 Reduce Accidents

16. THE EFFECT A CERTAIN CHEMICAL DEPENDS
ON SEVERAL FACTORS
• The routes of entry
• The physical properties of the substances
• Work practices
• The nature of the exposure
• Combined exposures
• The susceptibility of workers
• Toxicity

17. EFFECT OF CHEMICALS
- Causing irritation
- Allergies
- Lack of oxygen
- Systemic poisoning
- Cancer
- Damage to the unborn fetus
- Effects on the future generations
- Pneumoconiosis (Dusty lung)

33. CONTROLLING CHEMICAL
HAZARDS IN THE WORKPLACE
• Reduce or eliminate the use of hazardous
chemicals whenever possible.
• Maintain adequate ventilation systems to reduce
concentrations of airborne chemicals.
• Practicing good personal hygiene (e.g. washing
hands) and maintaining regular workplace
cleaning routines.
• Learn how to avoid carrying hazardous
substances home.

34. • Introduce administrative controls to minimize exposure to
chemicals (e.g. rotate workers through different jobs or
locations.
• Perform maintenance work in off-hours so that accidental
release of toxic substances will affect fewer workers.
• Use personal protective equipment and devices.
• Maintain equipment in good order to prevent leaks and
breakdowns that may release toxic substances.

43. GENERAL TIPS FOR CHEMICAL SAFETY
now how to protect yourself from the health hazards of
the chemicals you use.
• Read the warning labels on any chemical before you use
it.
• Remember that an unlabeled chemical is a dangerous
one.
• Never sniff or smell an unlabeled chemical.
• Follow thedirections and precautions listed on the
label.
• Follow ways to dispose a chemical properly.

50. Purpose of OSHA’s Hazard
Communication Standard
Hazard
Communication
Program
Container
Labeling
Safety
Data Sheet
SDS
Program
Label
To ensure that employers and employees know about work
hazards and how to protect themselves so that the incidence of
illnesses and injuries due to hazardous chemicals is reduced.

51. Who is covered?
OSHA’s Hazard Communication (HazCom) Standard applies to:
▶General industry
▶Shipyard
▶Marine terminals
▶Longshoring
▶Construction
▶Chemical manufacturers
▶Importers
▶Employers
▶Employees

52. Why is a written program required?
▶ ENSURES THAT ALL EMPLOYERS
RECEIVE THE INFORMATION
THEY NEED TO INFORM AND
TRAIN THEIR EMPLOYEES
▶ PROVIDES NECESSARY HAZARD
INFORMATION TO EMPLOYEES
(f) "Labels and other
forms of warning."
(g) “Safety data sheets."
(h) "Employee
information and
training."
HazCom Program

53. Written HazCom Program Requirements
▶ LIST KNOWN HAZARDOUS CHEMICALS
▶ PROVIDE SAFETY DATA SHEETS (SDS)
▶ INFORM EMPLOYEES OF HAZARDOUS OPERATIONS IN THEIR
AREA
▶ INFORM EMPLOYEES ABOUT HAZARDS OF NON-ROUTINE
TASKS
▶ WRITTEN HAZCOM MUST BE AVAILABLE UPON REQUEST TO
EMPLOYEES OR THEIR DESIGNATED REPRESENTATIVE

54. Container Labeling in the Workplace
▶ EFFECTIVE 2012, ALL CHEMICALS MUST BE LABELED USING
THE GLOBALLY HARMONIZED SYSTEM (GHS)
▶ THERE ARE 6 ELEMENTS OF A GHS LABEL:
Signal Word
Manufacturer Information
GHS Symbol
Precautionary Statement
Hazard Statement
Product Name
https://www.bradyid.com/en-us/applications/ghs-labeling-requirements

55. Primary vs Secondary Container Labeling
▶ PRIMARY CONTAINERS MUST BE LABELED FOLLOWING GHS
GUIDELINES
▶ Bags, barrels, bottles, boxes, cans, cylinders, drums
▶ Received from manufacturer
▶ SECONDARY CONTAINERS HOLD CHEMICALS TRANSFERRED
FROM PRIMARY CONTAINERS
▶ Spray bottles, jugs, jars
▶ Must comply with GHS except when:
▶ Container stays within the work area and in possession of the
worker who filled it
▶ Material is used within the work shift of the individual who filled it

56. Globally Harmonized System (GHS)
▶ The purpose of the GHS is to
standardize hazard
communication worldwide
▶ OSHA’s HazCom standard
incorporates GHS classifications
and labeling
▶ New SDS must incorporate GHS
system

57. Safety Data Sheets
▶ PREPARED BY THE CHEMICAL MANUFACTURER OR
IMPORTER
▶ MUST DESCRIBE:
▶ Physical hazards, such as fire and explosion
▶ Health hazards, such as signs of exposure
▶ Routes of exposure
▶ Precautions for safe handling and use
▶ Emergency and first-aid procedures
▶ Control measures

58. Safety Data Sheets (cont’d)
▶ MUST BE IN ENGLISH AND INCLUDE INFORMATION
REGARDING THE SPECIFIC CHEMICAL IDENTITY AND
COMMON NAMES
▶ MUST PROVIDE INFORMATION ABOUT THE:
▶ Physical and chemical characteristics
▶ Health effects
▶ Exposure limits
▶ Carcinogenicity (cancer-causing)
▶ Identification (name, address, and telephone number) of the
organization responsible for preparing the sheet
▶ MUST BE READILY ACCESSIBLE TO EMPLOYEES IN THEIR WORK
AREA

59. Safety Data Sheets (cont’d.)
▶ IF NO SDS HAS BEEN RECEIVED
FOR A HAZARDOUS CHEMICAL,
EMPLOYER MUST CONTACT THE
SUPPLIER, MANUFACTURER, OR
IMPORTER TO OBTAIN ONE AND
MAINTAIN A RECORD OF THE
CONTACT
▶ AS OF 2012, SDS HAVE NEW
FORMAT AND REQUIREMENTS

60. Safety Data Sheets ( cont’d)
1. IDENTIFICATION (PRODUCT,
MANUFACTURER, CONTACT)
2. HAZARD IDENTIFICATION
3. INGREDIENTS
4. FIRST AID MEASURES
5. FIRE FIGHTING MEASURES
6. ACCIDENTAL RELEASE MEASURES
7. HANDLING AND STORAGE
8. EXPOSURE CONTROLS/PERSONAL
PROTECTION
9. PHYSICAL AND CHEMICAL PROPERTIES
10. STABILITY AND REACTIVITY
11. TOXICOLOGICAL INFORMATION
12. ECOLOGICAL INFORMATION (NON-
MANDATORY)
13. DISPOSAL CONSIDERATIONS (NON-
MANDATORY)
14. TRANSPORT INFORMATION (NON-
MANDATORY)
15. REGULATORY INFORMATION (NON-
MANDATORY)
16. OTHER INFORMATION

61. CHEMICAL HAZARDS
Types of Chemical Hazards
 Irritant chemicals
 Sensitizers
 Toxic Chemicals
 Asphyxiants
 Anesthetic and Narcotic
 Systematic poisons
• Respiratory fibro gens
• Carcinogens

62. CHEMICAL HAZARDS
• Irritant chemical: Primary irritant cause
inflammation in one of the body’s defense
mechanisms. It is the reaction of tissue to harm
which in sufficient to kill the tissue and is typified by
construction of the small vessels in the affected area,
dilution of the blood vessels, increased permeability
of vessel walls, and migration of the white blood cell
and defensive cells to the invading harmful chemicals
i.e. sulphur dioxide may make a blistering effect on
Upper respiratory system.

63. CHEMICAL HAZARDS
• Sensitizers: generally sensitizers may not on
first contact result in any ill effects, although
cellular changes can be induced and the
body’s immune system affected (some
chemicals may act as primary irritants as well
as sensitizers).

64. CHEMICAL HAZARDS
• Anesthetic and Narcotic: anesthetic and
narcotic e.g. hydrocarbons and certain
derivatives such as the various chlorinated
solvents or other, exert a depressant action on
the central nervous system i.e. Aliphatic
alcohols, petroleum etc.

65. CHEMICAL HAZARDS
• Systematic poisons: Systematic poisons attack
organs other than the initial site of contact. The
critical organs are the kidneys, liver, blood and
bone marrow. Many halogenated hydrocarbons
are effects the Visceral organs in Hematopoietic
(i.e. blood-forming system) Nervous system.

66. CHEMICAL HAZARDS
• Respiratory fibro gens: The hazard of
particulate matter is influenced by the toxic
and size and morphology of the particles. The
critical size of dust (and aerosol) particles is
0.5 to 7 µm, since these can become
deposited in the respiratory bronchioles and
alveoli. i.e. Free crystalline silica.

67. CHEMICAL HAZARDS
• Carcinogens: Cancer is a disorder of the body’s
control of the growth of cells. The diseases
may be a genetic or influenced by life style or
exposure to certain chemicals, termed
carcinogens i.e. Coal tar pitch dust, Asbestos
etc.

68. CHEMICAL HAZARDS
• Toxic Chemicals: Chemicals having following
values of acute toxicity and which, owing to
their physical and chemical property, are
capable of producing major accidents hazards.

69. CHEMICAL HAZARDS
• TOXICITY: IDLH: the Immediately Dangerous to
Life and Health are not occupational exposure
limits similar to the TLV. They were developed by
National Institute of Occupational Safety and
Health to guide respirators selection. It is that
maximum level of concentration of an air borne
contamination from which one could escape
within 30 minutes without any impairing
symptoms or any irreversible health effects. It is
reported in ppm or mg/m3.

70. CHEMICAL HAZARDS
• TLV (THRESHOLD LIMIT VALUES): The two or more
hazardous substances are present, their combined effect
rather than that of individually, should be given primary
consideration. The effects of the different hazards should be
consideration as additive.
• Time-Weighted Average: The TLV may be a Time-
Weighted Average (TWA) figure that would be
acceptable for 8 hours exposure. For some
substances such as an extremely irritating one, a
Time weighted Average concentration would not be
acceptable.

71. CHEMICAL HAZARDS
• TLV-STEL: Some substances have a Short-Term
Exposure Limit. The 8 hours TLV remains
within the limit. Such limits were assigned to
substances exerting toxic even over a short
period of time. STEL exposure should not be
more than 4 per day with at least 60 minutes
gap between successive exposures.

72. CHEMICAL HAZARDS
• LTEL (Long-Term Exposure Limit): Long-term
exposure limit are concerned with the total
intake of contaminants (or contaminants) over
a long period.
• LD 50 for acute local Toxicity: It is that dose of
the substance administered which is most
likely to cause death within in one half of both
male and female young adult rats. The result
is expressed in mg per kg body weight.

73. CHEMICAL HAZARDS
• LC 50 for acute toxicity in Inhalation: It is that
concentration of vapor, mist, or dust which,
administered by continuous inhalation to both
male and female young adult rat for one hour
causes death within 14 days in one half of the
animals tested.
• LC Lo (Lethal Concentration Low): It is the lowest
concentration of a substance in air other than
LC50 which has been reported to have caused
death in humans and animals.

74. CHEMICAL HAZARDS

75. • LOWER EXPLOSIVE LIMIT: The minimum concentration of a
gas, vapor, mist or dust in air at a given pressure and
temperature that will propagate a flame when exposed to an
efficient ignition source. Generally expressed as % by volume
for gases and vapors, and as mg/m3 for mists or dusts.
• MAXIMUM EXPOSURE LIMIT: The maximum concentration
of an airborne sub-stance, averaged over a reference period,
to which employees may be exposed by inhalation under any
circumstance. Thus, exposure to a chemical assigned an MEL
must be low as is reasonable practicable and, in any case,
below the MEL.
• UPPER EXPLOSIVE LIMIT(UEL): The maximum concentration
of gas, vapor, mist or dust in air at a given pressure and
temperature in which a flame can be propagated.

76. CHEMICAL HAZARDS
• Risk Control: Exposure to chemicals, resulting in toxic
effects or oxygen deficient -atmospheres, may arise in
a variety of industrial situations. A summary of
common sources, clearly this is not exhaustive since
exposure may result whenever materials are mixed,
machined, heated, dispersed (or) otherwise processes
(or) used. The precautions naturally vary in each case.
For example, to avoid improper admixture of chemical
will require- adequate training, instruction and
supervision of workers Identification of chemicals by
name and code numbers Segregated storage of
incompatible substances.

77. WHAT IS AIR SAMPLING ?
A MEANS OF COLLECTING CONTAMINATES FROM AIR
TO IDENTIFY AND QUANTIFY THE CONCENTRATION OF
THE CONTAMINATES.
• Typically, we need to concentrate the contaminates with
some sort of media. the exceptions is when we take “whole
air samples” then the concentration step takes place in the
lab.

78. •Concentration are calculated in either dimensionless
terms: PPM OR PPB
OR
•Concentrations are calculated in mass per volume
terms: g/m3 OR mg/m3
µ

80. COMMONLY SAMPLED AIR CONTAMINANTS
Ambient Air
• Particulates
• BTEX/VOCs
• Pesticides, PAHs, PCBs
• Ozone
• Carbonyls
• Carbon Monoxide
• Nitrogen Dioxide
• Sulfur Dioxide
• Lead
Indoor Air / Industrial Hygiene
• BTEX/VOCs
• Carbonyls
• Hydrogen sulfide
• Isocyanates – TDI, MDI, HDI
• Acid vapors
• Metals – Lead, Cadmium,
Hexavalent Chromium

81. WHAT ARE WE SAMPLING (PEOPLE OR PLACES)?
Personal Sampling
What concentration are people
exposed to?
• Samples taken in the
breathing zone.
Area Sampling
What is the concentration in
the air?
• Fence line monitoring
• Evaluating engineering
controls
• Smoke Stacks

82. HOW LONG TO SAMPLE?
• GRAB SAMPLING
~1-MINUTE
• STEL SAMPLING (SHORT-TERM EXPOSURE LIMIT)
15-MINUTE EXPOSURE
• TWA SAMPLING (TIME WEIGHTED AVERAGE)
8-HOUR EXPOSURE (TYPICAL PERSONAL SAMPLING TIME)
• RISK ASSESSMENT
24-HOUR
• REAL TIME
CONTINUOUS SAMPLING

83. TYPICAL CONCENTRATIONS OF VARIOUS SOURCES

84. AIR SAMPLING - THE 3
FACTORS
WHEN TAKING AIR SAMPLES - THERE ARE THREE FACTORS
IN DETERMINING THE CONCENTRATION:
• SAMPLING RATE
– ACTIVE SAMPLERS – REQUIRES A PUMP TO CONTROL
THE FLOW RATE
– PASSIVE SAMPLER – DESIGN OF THE SAMPLER DICTATES
THE FLOW RATE “IT’S FIXED” BY DIFFUSION

85. • SAMPLING TIME
– HOW LONG OF A SAMPLE DO WE NEED?
• SAMPLE VOLUME
– THE SAMPLE VOLUME IS CALCULATED BY MULTIPLYING
THE FLOW RATE X SAMPLING TIME:
FLOW RATE X SAMPLING TIME = SAMPLE VOLUME
NOTE: SAMPLE VOLUME IS DEPENDENT ON THE
TEMPERATURE AND PRESSURE DURING SAMPLING, SO
CORRECTION IS NORMALLY REQUIRED.

86. WHAT HAZARDS (ANALYTES) ARE WE SAMPLING
GASES AND VAPOR –
• TYPICALLY NEED TO BE ADSORBED
USING AN ADSORBENT, SUCH AS
CHARCOAL, SILICA GEL, POROUS
POLYMER, OR SYNTHETIC CARBONS
• REACTIVE ANALYTES LIKE
ALDEHYDES, AND ISOCYANATES
NEED TO BE DERIVATIZED TO
STABILIZE THEM UNTIL THEY CAN BE
ANALYZED.
• AEROSOLS AND PARTICLES –
• TYPICALLY, ARE TRAPPED
USING A FILTER MEDIA, OR
LIQUID MEDIA

87. WHAT ANALYTES ARE WE SAMPLING
Gases and Vapor – typically need to be adsorbed using a
adsorbent, such as charcoal, silica gel, porous polymer, or
synthetic carbons
Reactive analytes like carbonyls such as formaldehyde, and
isocyanates need to be derivatized into stabilize analytes
until they can be analyzed.
Aerosols and Particles – typically are trapped using a
filter media, or Liquid Media

88. HOW TO TAKE THE AIR SAMPLES
Passive Sampling
– also called Diffusive Sampling
• Relies on the natural diffusion of analytes through the
sampler
Active Sampling
– also called Pumped Sampling
• Relies on physically pulling the analytes through the
sampler
• Requires an air sampling pump
• Concentrating the analytes on some sort of media
(adsorbents, or filters)

89. WHAT IS PASSIVE SAMPLING?
The contaminated air enters the device by diffusing onto the
adsorbent media inside the device. The analytes in the air are
concentrated on to the media. The mass uptake of the monitor
is controlled by the design of the device that surrounds the
adsorbent media
Adsorbent
Diffusive
Membrane
O2 H20
CH2Cl2

90. PASSIVE SAMPLING
Radiello
-BTEX/VOC’s (SD & TD)
-Aldehydes
-Ammonia
-Anesthetic Gases & Vapors
-Hydrochloric Acid (HCl)
-Hydrofluoric Acid (HF), Nitrogen Dioxide (NO2), Sulfur Dioxide
(SO2)
-1,3-Butadiene & Isoprene
Thermal Desorption Tubes w/Diffusion Caps
-Any single bed Thermal Desorption tube
-Compound diffusion rates will need to be
determined by the investigator
SPME
-Time-Weighted Average (TWA)

91. ACTIVE SAMPLING
Is performed by pulling air (vacuum) through the
sampling media using an air sampling pump.
The chemicals in the air are concentrated on the
adsorbent media.
O2,H20
CH2Cl2
Pump

92. SOLUTION SAMPLING: IMPINGER & BUBBLER
Impinger  Small Hole in Glass Tip - Used to sample aerosols and
particles
Sample
Inlet
To Pump
Adsorber
Solution
Bubbler  Fritted Glass – Used to sample gases and vapors
Impinger Bubbler

93. FILTERS & CASSETTES
Used for sampling particles (dust)
and aerosols
Different filter materials are
available
• PVC, Cellulose ester, PTFE, Glass Fiber

94. WHOLE AIR SAMPLERS
Whole air samplers do not concentrate the sample, the air is
included with the sample.
If the sample needs to be concentrated - it is done in the lab
• Used to sample compounds that can not be trapped or concentrated
– Methane, Carbon Monoxide

95. WHOLEAIR SAMPLING PRODUCTS
Gas Sampling Bags
• Tedlar® Film
• Supel™Inert Film – 2 valves; 5 sizes
• Supel™ Inert Foil – 2 valves; 4 sizes
Glass Sampling Bulbs
Used as alternatives to gas sampling bags
• 2 Stopcock types: Glass & PTFE
• 4 Sizes: 125 mL, 250 mL, 500 mL, 1 L
Bag Samplers (Negative Pressure Pump)
• 4 models available
• Battery charges are a separate purchase

96. GAS SAMPLING BAGS
Note: Other products can be used in
conjunction w/ gas sampling bags to
analyze the captured air sample.
Supel-Inert Film
VOCs; Tedlar Alternative Film
Example uses:
•VOCs – EPA TO-14A/15; TO-17
•Carbon Dioxide
•Carbon Monoxide
•Making Calibration Mixes
Supel-Inert Foil
Light & Permanent Gases

97. AIR SAMPLING BAG TECHNIQUE
VOC’s along with the air are collected in the
bag. Typically the bag is filled by the
exhaust port of an air sampling pump.
Typical flow rates: 10-1000mL/min
2.
Gas
Sampling
bag
Inlet
A portion of the gas sample is
injected into a Gas Chromatography
system using Gas- Tight Syringe
(Typically 1-500uL) or other sample
prep method – ORBO, TDU, etc
1.

98. BAG SAMPLER
•(SOMETIMES CALLED A LUNG SAMPLER)
• THE INTERNAL PUMP CREATES A VACUUM INSIDE THE
BOX, THIS CREATES A NEGATIVE PRESSURE THAT
CAUSES AIR TO RUSH INTO THE BAG TO EQUALIZE THE
PRESSURE IN THE BOX.
• ADVANTAGES OF USING A BAG SAMPLER:
•SAMPLE IS NOT EXPOSED TO THE PUMP PARTS
–PREVENTS CONTAMINATING THE PUMP
–COMPOUNDS DO NOT GET STUCK IN THE PUMP
Vent Valve
Air
Sampling Chamber
Pump
Exhaust
Tube

99. ADSORBENT TUBES (ACTIVE SAMPLERS)
Solvent Desorption Tubes
• ORBO Tubes (Supelco’s Trade name)
• Over 75 configurations available
–Charcoal
–Carbons
–Silica Gel
–Porous Polymers
–Coated Adsorbents
Thermal Desorption Tubes
• TD Tubes (Carbotrap-XXX Trade name)
• Single Bed Tubes
• Multi-Bed Tubes

100. SOLVENT DESORPTION TUBES
Sampling
•Tips of tubes are broke off
•Tube is connected to a sampling pump and the flow rate is adjusted.
•After sampling –caps are placed on the tubes until they are analyzed.
Work up
•The adsorbents are removed from the tube
• Each adsorbent bed is placed in a separated vial
• Typically the glass wool plugs are discarded
•Solvent is added to the vials (carbon disulfide is popular)
•Vials are sonicated for ~ 30 minutes
•An aliquot is removed and injected into a chromatographic system for analysis
Note:
Break-through has occurred - If analyte is detected in the back-up bed

101. ULTRA-CLEAN POLYURETHANE FOAM (PUF)
SAMPLERS FOR PESTICIDES, PAHS, PCBS
AND DIOXINS IN AIR
Polyurethane Foam
ORBO 2000 ORBO 2500
ORBO 1000 ORBO 1500
Small PUF Methods (ORBO-1000/1500)
ASTM D4861 Pesticides/PCBs
ASTM D4947 Chlordane/Heptachlor
EPA IP-8 Pesticides/PCBs
EPA TO-10A Pesticides/PCBs
Large PUF Methods (ORBO-2000/2500)
ASTM D6209 PAHs Pesticides/PCBs
EPA IP-7 PAHs
EPA TO-4A Pesticides/PCBs/Dioxins
EPA TO-9A Dioxins
EPA TO-13 PAHs

102. COATED ADSORBENTS
Why?
• Converts (i.e., derivatizes) reactive analytes into a less volatile
derivatives, making them more stable
• Typically the derivatives also increases the detectors response
– resulting in better sensitivity
• Our most popular coated sampler
– LpDNPH Cartridges for Aldehydes and Ketones
Rezorian
How to connect?
ORBO Tube

103. THERMAL DESORPTION WHAT IS IT?
A sample preparation technique used with gas
chromatography
The sample is collected onto one or more adsorbents
packed inside a glass or, stainless steel tube.
•The packed tube is heated (Thermal) and the compounds are
released into the carrier gas (Desorption) where they are swept
onto the GC column and analyzed by the gas chromatograph.

104. WHAT IS THERMAL DESORPTION?
Thermal Desorption Tube can is used to collect volatile
organic analytes, which can be analyzed by gas
chromatography
Can not be used to sample:
–Analytes that require derivatization before analysis
–Analytes sensitive to thermal degradation
–Analytes larger than >n-C40

105. THERMAL DESORPTION TUBES
Requires a thermal desorption instrument for
analysis
Tubes are available in Glass and Stainless Steel
–Glass is more inert, can visually see the integrity of
the packing
–Stainless Steel - more durable- will not break
Reusable ~100 times
Single and Multi-beds tubes available

106. THERMAL DESORPTION – HOW IT WORKS ?
Gas Chromatograph
Thermal Desorber Heat
and flow sweeps the
compounds off
of the tube
The Thermal Desorption
Tube is placed in a thermal
desorber where it’s
desorbed.
100% of
the sample
can be
sent to the
detector
Heated Transfer Line
~300
°C
Carrier
Gas

107. Single-Bed - Thermal Desorption Tube
Typical 1-Bed Tube (Tenax TA)

108. Multi-Bed - Thermal Desorption Tube
Typical 3-Bed Tube (Carbotrap 300)