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... activation energy which is the energy required to initi

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Title: ... activation energy which is the energy required to initi


1
Hazardous Chemicals Awareness Level
  • Wes Adams
  • Asheville-Buncombe Technical Community College
  • Note Permission to use this presentation is
    granted as long as you give credit to the author,
    Wes Adams.

2
HAZMAT Awareness
  • Topics to be covered
  • MSDS Sheets
  • NFPA System
  • UN Identification Number
  • Emergency Response Guidebook
  • Factors Affecting the Rate of Reaction
  • The DOT Hazardous Materials Classes along with
    the particular hazards of each class.

3
MSDS Sheets
  • An Material Safety Data Sheet (MSDS) is a
    technical bulletin containing detailed
    information about a hazardous substance.
  • OSHA requires that manufacturers prepare an MSDS
    for each chemical that it sells.
  • The MSDS contains more extensive information than
    is conveyed on the label.
  • The MSDS must accompany each chemical it ships
    the first time that the chemical is shipped to
    that recipient.

4
MSDS Sheets
  • The following minimum information must be
    provided in the MSDS
  • The identity of the product as used on the
    container label.
  • The chemical and common name for all ingredients
    present in concentrations greater than 1 and
    0.1 for a cancer causing substance (carcinogen).
  • The physical and chemical properties of the
    hazardous components.

5
MSDS Sheets
  • The physical and health hazards, including signs
    and symptoms of exposure and/or prior and/or
    existing conditions that can warn against
    exposure.
  • Primary routes of entry into the body.
  • Any known exposure limits.
  • Whether the hazardous substance is a carcinogen.
  • Precautions for safe handling and use.

6
MSDS Sheets
  • Procedure for spill or leak cleanup.
  • Control measures
  • Emergency first-aid procedures.
  • The date of preparation
  • The name, address, and telephone number of the
    company or responsible employee distributing the
    MSDS.

7
NFPA System
  • The National Fire Protection Association (NFPA)
    recommends certain markings for use on storage
    tanks, exterior building walls, pipelines and
    other relevant locations.
  • This procedure for identifying potential hazards
    associate with a chemical is called the NFPA 704
    system.
  • NFPA ratings can be found on the MSDS sheet.

8
NFPA System
  • The NFPA system uses a diamond with color coded
  • Blue is for the health hazard.
  • Red is for the flammability hazard.
  • Yellow is for the reactivity hazard.
  • White is for special hazards.
  • A number is placed in each section ranging from
    0-4. A 0 means no hazard and a 4 means an extreme
    hazard.

9
NFPA System
  • The following seven symbols are employed in the
    white section of an NFPA diamond
  • A radiation hazard symbol is a three bladed
    propeller.
  • The letter W with a line trough it is a caution
    against applying water.
  • The letters OXY indicate that the material is
    an oxidizer.
  • The letter P indicates there is a potential for
    the material to under go auto-polymerization.
  • The Word ACID indicate that the material is an
    acid.
  • The letters ALK indicate that the material is
    an alkali (base).
  • The letters COR indicate that the material is
    corrosive.

10
NFPA System
11
Identification Number
  • UN or NA preceding a number indicates the
    identity of the chemical.
  • UN indicates internationally transported
    chemicals while NA refers to those only
    transported in the US and Canada.
  • In addition to these placards the UN number may
    also be inset into the appropriate placard.

12
Emergency Response Guidebook
Also Available on the Web
13
Emergency Response Guidebook
  • After obtaining the identification number consult
    the North American Emergency Response Guide Book
  • The yellow pages list the materials in numerical
    order by UN ID number.
  • The blue pages list the materials in alphabetical
    order.

14
Emergency Response Guidebook
  • The orange bordered pages list 172 individual
    guide numbers listing emergency response actions
    for particular materials.
  • The green bordered pages give initial isolation
    and protective distances for the highlighted
    entries in the yellow and blue sections.

15
Factors Affecting the Rate of Reaction
  • There are 5 important factors which affect rates
    of reactions
  • Nature of the Material
  • Reactant Concentration
  • Temperature
  • Action of Catalysts
  • Surface Area

16
Factors Affecting the Rate of Reaction
  • Nature of the Material includes the chemical
    composition of the substance and the physical
    state in which it exists.
  • For example white phosphorous ignites
    spontaneously in air while wood requires an
    ignition source and water will not burn.
  • Generally reaction occurs fastest in the gas
    phase, the second fastest in the liquid phase,
    and much more slowly in the solid phase.

17
Factors Affecting the Rate of Reaction
  • Reactions in general go more quickly at higher
    concentrations.
  • For example flammable materials burn much more
    quickly at high oxygen concentrations.
  • Since air is 78 nitrogen and 21 oxygen by
    volume, nitrogen serves to lower the oxygen
    concentration and reduce the rate of combustion.

18
Factors Affecting the Rate of Reaction
  • As a general rule the rate of the reaction
    increases as the temperature increases.
  • For example food spoils when not refrigerated.
  • As a general rule the rate of a chemical reaction
    doubles for every rise of 18oF (10oC).

19
Factors Affecting the Rate of Reaction
  • Reactions also proceed more quickly in the
    presence of a catalyst.
  • Catalysts speed up a reaction without being used
    up in the reaction.
  • This is usually done by lowering the activation
    energy which is the energy required to initiate a
    chemical reaction.
  • The combustion of hydrogen and oxygen will not
    occur without a spark unless a piece of platinum
    is added and then they explode violently.

20
Factors Affecting the Rate of Reaction
MnO2 causes the Catalytic Decomposition of H2O2
to liberate oxygen which will increase the
combustion rate.
21
Factors Affecting the Rate of Reaction
  • Generally reactions occur more quickly with a
    greater surface area.
  • For example a flammable liquid will burn more
    quickly in a container that will allow it to
    assume the largest surface area.

22
Factors Affecting the Rate of Reaction
Burning Licompodium Powder
23
Hazard Class
24
Class 1 Explosives
  • There are two general types of explosive
    materials
  • Chemical explosives detonate as a result of the
    application of friction, mechanical impact, or
    heat usually used for demolition and other
    destructive acts.
  • It is distinguished from gasoline and flammable
    gases which will seem to explode when ignited.
  • They are also distinguishable from nuclear
    explosives, which detonate by nuclear phenomena.

25
Class 1 Explosives
26
Class 1 Explosives
  • The rapidly expanding gases often exceeds the
    speed of sound and cause shock waves.
  • These shock waves are associated with the
    explosives shattering power called its brisance.
  • The brisance is an important factor in choosing
    the correct explosive for a particular use, like
    clearing rock for a road.
  • Sometimes so-called chemical explosives are a
    mixture of substances that appear to detonate
    which includes gunpowder and some blasting agents.

27
Class 1 Explosives
Nitrogen Triiodide is an explosive.
28
Class 2 Gases
  • A division 2.1 (flammable) gas is any material
    that is a gas at 68oF or less and 14.7 psi of
    pressure and is one of the following
  • Ignitable at 14.7 psi when in a mixture of 13 or
    less by volume with air.
  • Possesses a flammable range at 14.7 psi of at
    least 12 regardless of the lower limit.

29
Class 2
A Bunsen Burner Flame is fueled by Natural gas.
Different Metals in the flame will change the
flame from blue to different colors. This also
works for liquids.
30
Class 2 Gases
  • A division 2.2 (non-flammable) gas is any
    material or mixture that does one of the
    following
  • Exerts in its packaging an absolute pressure of
    41 psi or greater at 68oF.
  • Does not meet the definition of division 2.1 or
    2.3

31
Class 2 Gases
A small amount of water is placed into a can and
heated when rapidly cooled the water vapor
condenses leaving a vacuum which allows the air
pressure to crush the can.
32
Class 2 Gases
  • A division 2.3 (poison by inhalation) gas is a
    material that is a gas at 68oF or less at 14.7
    psi and is one of the following
  • Known to be so toxic to humans as to pose a
    health hazard during transportation.
  • In absence of data on human toxicity, is toxic to
    laboratory animals and has and LC50 (lethal
    concentration 50 of the time) less than 5000
    mL/m3.

33
Class 2 Gases
  • Some examples of toxic gases are
  • Carbon Monoxide
  • Hydrogen cyanide
  • Sulfur dioxide
  • Hydrogen Sulfide
  • Nitrogen Dioxide
  • Anhydrous Ammonia

34
Class 2 Gases
Copper and Nitric Acid generate Nitrogen Dioxide
35
Class 3 Flammable Liquids
  • The DOT defines a flammable liquid as either of
    the following
  • Any liquid having a flash point not more than
    141oF.
  • Any liquid with a flash point at or above 100oF
    that is intentionally heated and offered for
    transportation or transported at or above its
    flash point within bulk packaging.
  • A combustible liquid has a flash point above
    141oF and below 200oF

36
Flammability
Burning Methanol
37
Storage and Transport of Compresses Gases
  • Large amounts of compressed gases or liquefied
    gases are transported in large tanks pulled
    behind the vehicle or as its own separate rail
    car.
  • Such a tank exposed to direct flames will
    rupture.
  • If a liquefied gas is flammable a Boiling Liquid
    Expanding Vapor Explosion (BLEVE) can occur.
  • A BLEVE occurs when a released liquid is rapidly
    heated to temperature above its boiling point.
  • Some BLEVEs have resulted in fireballs with radii
    of 900 ft.

38
Storage and Transport of Compresses Gases
39
Class 4 Flammable Solids
  • The DOT defines a flammable solid as any of the
    following
  • Any of several wetted explosives
  • Any of several self-reactive materials that are
    thermally unstable and can undergo a strongly
    exothermic (gives off heat) decomposition even
    without the participation of atmospheric oxygen
  • A readily combustible solid.

40
Class 4 Flammable Solids
Burning Magnesium in the presence of Carbon
dioxide.
41
Class 4 Flammable Solids
  • The DOT defines a spontaneously combustible
    material as either of the following
  • A pyrophoric material is a liquid or solid that
    even in small quantities and without external
    ignition source can ignite within five minutes
    after coming in contact with air.
  • A self-heating material is a material that when
    in contact with air and without an energy supply
    is liable to self heat.

42
Class 4 Flammable Solids
Phosphorus in Air
43
Class 4 Flammable Solids
  • The DOT defines a dangerous when wet material as
    a material that, by interaction with water, is
    likely to become spontaneously flammable or to
    release a flammable or toxic gas or vapor at a
    rate greater than 28 in3/lb (1 L/kg) per hour.

44
Class 4 Flammable Solids
Calcium Carbide and Water liberate flammable
acetylene gas.
45
Class 5 Oxidizers and Organic Peroxides
  • The DOT defines two classes of oxidizers
  • An oxidizer (division 5.1) is a material that can
    cause or enhance the combustion of materials,
    generally by yielding oxygen.

46
Class 5 Oxidizers and Organic Peroxides
Ammonium Nitrate Zinc and Water
Potassium Chlorate and Gummy Bear
Copper Silver Redox
47
Class 5 Oxidizers and Organic Peroxides
  • An organic peroxide (division 5.2) is an organic
    compound containing oxygen in the bivalent OO
    structure.
  • Organic peroxide formation is especially
    susceptible in some ethers especially diglyme,
    diethyl ether, dioxane, glyme, isopropyl ether,
    tetrohydrofuran.

48
Class 5 Oxidizers and Organic Peroxides
Test for organic peroxides at the neck of old
ether bottles before opening.
49
Class 6 Poisonous and Infectious Materials
  • The DOT defines poisonous and infectious
    materials as follows
  • A poisonous material is a material other than a
    gas that is known to be toxic to humans to
    present a hazard during transport or
  • Is presumed to be toxic because of data obtained
    from tests performed on animals.
  • Is an irritating material with properties similar
    to tear gas and causes extreme irritation,
    especially within confined spaces.
  • Examples include cyanide containing salts,
    asbestos, and pesticides.

50
Class 6 Poisonous and Infectious Materials
  • An infectious material is a viable micro organism
    or its toxin that causes or can cause disease in
    humans or animals.
  • Potentially infectious substances include
  • Blood and blood products
  • Saliva, vomit, urine
  • Semen or vaginal secretions
  • Skin, tissue, cell cultures
  • Other body fluids (particularly if blood is
    visible).

51
Class 6 Poisonous and Infectious Materials
52
Class 7 Radioactive Materials
  • A radioactive material is any material or any
    combination of materials that spontaneously emits
    ionizing radiation having a specific activity
    greater than 70 Becquerels per gram.
  • Radioactive White-I, Yellow-II, and Yellow-III
    alerts emergency response workers to increasing
    radioactivity.
  • White-I is the least radioactive and Yellow-III
    is the most radioactive.

53
Class 7 Radioactive Materials
A Geiger Counter is used to measure radioactivity.
54
Class 8 Corrosive Materials
  • A corrosive material is both of the following
  • A liquid or solid that causes visible destruction
    or irreversible alterations in skin tissue at the
    site of contact.
  • A liquid that has a severe corrosion rate on
    steel or aluminum, as measured in accordance with
    certain prescribed DOT testing procedures.

55
Class 8 Corrosive Materials
Sodium Biarbonate HCl liberates CO2 gas.
Magnesium HCl liberates H2 gas
56
Class 9 Miscellaneous Hazardous Materials
  • The DOT defines a miscellaneous hazardous
    material as a material that presents a hazard
    during transportation, but is not included in any
    other hazard class.
  • These materials are any material that has
    anesthetic, noxious, elevated-temperature
    substances, hazardous wastes and marine
    pollutants, and magnetized materials.
  • ORM-D materials are also class 9.

57
Class 9 Miscellaneous Hazardous Materials
Hot water when transported is an elevated
temperature material an is therefore Class 9
58
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