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2
Hazardous
 Materials:
 Properties
and Effects
2
             Objectives (1 of 7)
• Describe the following properties:
  – Boiling point
  – Chemical reactivity
  – Corrosivity (pH)
  – Flammable (explosive) range [lower explosive
    limit (LEL) and upper explosive limit (UEL)]
  – Flash point
2
           Objectives (2 of 7)
– Ignition (autoignition) temperature
– Particle size
– Persistence
– Physical state (solid, liquid, gas)
– Radiation (ionizing and non-ionizing)
– Specific gravity
2
          Objectives (3 of 7)
– Toxic products of combustion
– Vapor density
– Vapor pressure
– Water solubility
– Physical change and chemical change
2
            Objectives (4 of 7)
• Describe radiation (non-ionizing and
  ionizing) as well as the differences among
  alpha and beta particles, gamma rays,
  and neutrons.
2
            Objectives (5 of 7)
• Describe the differences between the
  following pairs of terms:
  – Contamination and secondary contamination
  – Exposure and contamination
  – Exposure and hazard
  – Infectious and contagious
  – Acute and chronic effects
  – Acute and chronic exposures
2
            Objectives (6 of 7)
• Describe the following types of weapons
  of mass destruction:
  – Nerve agents
  – Blister agents
  – Choking agents
  – Irritants
2
            Objectives (7 of 7)
• Describe the routes of exposure to
  hazardous materials for humans
2
 Chemical and Physical Properties
                  (1 of 2)
• Characteristics of a substance
• Important to understand for hazardous
  substances/WMD
• Basis of good decisions on response
2
 Chemical and Physical Properties
                       (2 of 2)
• Are measurable
• They include:
  – Vapor density
  – Flammability
  – Corrosivity
  – Water reactivity
2
                 State of Matter (1 of 2)




The state of matter identifies the hazard as a solid, liquid, or gas.
2
          State of Matter (2 of 2)
• Helps predict what substance will do
  – How will it escape its container?
  – Why did the container fail?
• Influences the incident’s duration
  – In turn, informs emergency response plan
2
           Physical Change
• Can occur when chemicals are subjected
  to
  – Heat
  – Cold
  – Pressure
2
                   BLEVE
• Boiling Liquid/Expanding Vapor Explosion
  – Pressurized liquefied materials inside closed
    vessel are exposed to high heat
  – Results in physical change from liquid to gas
• Examples: propane, butane
• Expansion ratio: Describes the volume
  increase that occurs
2
            Chemical Reactivity
•   Also known as chemical change
•   Ability to transform at molecular level
•   Usually releases some form of energy
•   Examples
    – Steel when it rusts
    – Wood when it burns
2
      “You Are the Responder”
            Case Study
• What physical/chemical changes caused:
  – The rags to spontaneously ignite?
  – Failure of the small, propane cylinder?
  – Fire fighters and residents to experience skin
    irritation?
2
        Critical Characteristics of
           Flammable Liquids
•   Flash point
•   Ignition temperature
•   Flammable range
•   Only substances in gaseous or vapor
    state will combust
    – Solids and liquids produce vapor, then ignite
2
           Flash Point (1 of 3)
• Minimum temperature at which ignition
  results in flash fire
• Fire will go out once vapor fuel is
  consumed
2
               Flash Point (2 of 3)




Responders should always be mindful of ignition sources at
        flammable/combustible liquid incidents.
2
            Flash Point (3 of 3)
• Low flash point = higher ignition
  temperatures and vapor pressures
  – Examples: Gasoline, ethyl alcohol, acetone
• High flash point = lower ignition
  temperatures and vapor pressures
  – Example: #2 grade diesel fuel
2
                 Fire Point
• Temperature at which sustained
  combustion of vapor occurs
• Usually slightly higher than flash point
2
         Ignition Temperature
• Also known as autoignition temperature
• Temperature at which heated fuel ignites
  and continues to burn
• No external ignition source necessary
2
           Flammable Range
• Concentrations (%) of flammable vapor
  and air needed for fuel/air mixture to burn
• Defined by lower and upper limits:
  – Lower explosive limit (LEL)
  – Upper explosive limit (UEL)
• More dangerous material has wider range
2
         Vapor Pressure (1 of 3)
• Pertains to liquids inside closed container
• May be expressed in:
  – Pounds per square inch (PSI)
  – Atmospheres (atm)
  – Torr
  – Millimeters of mercury (mm Hg)
2
         Vapor Pressure (2 of 3)




The vapors released from the surface of any liquid must
      be contained if they are to exert pressure.
2
         Vapor Pressure (3 of 3)
• Influenced by ambient temperature
  – High temp. → increased vapor pressure
  – Low temp. → decreased vapor pressure
• Causes liquid to evaporate when released
  – High vapor pressure → evaporates quickly
  – Low vapor pressure → evaporates slowly
2
            Boiling Point (1 of 2)
• Liquid continually gives off vapors
• Molecules must overcome downward
  force of atmospheric pressure
• If maintained, all liquid will turn into gas
2
              Boiling Point (2 of 2)




The concept of boiling point versus atmospheric pressure.
2
           Vapor Density (1 of 2)
• Weight of vapor compared to weight of air
  – Expressed numerically (e.g., in the MSDS)
  – Air has set vapor density of 1.0
  – Vapor density > 1.0 = heavier; < 1.0 = lighter
• Affects gas’ behavior during release
• Lighter-than-air gases: “4H MEDIC ANNA”
2
               Vapor Density (2 of 2)



                         A.     B.




 A. Vapor density < 1.0 over the cylinder with the gas leak rising
upward. B. Vapor density > 1.0 over the cylinder with the heavier-
                          than-air leak.
2
          Specific Gravity (1 of 2)
• Compares weight of liquid chemical to
  weight of water
• Water has specific gravity of 1.0
• Materials with specific gravity < 1.0 float
• Materials with specific gravity > 1.0 sink
• Most flammable liquids float on water
2
              Specific Gravity (2 of 2)




Gasoline will float on water, whereas carbon disulfide will not.
2
             Water Solubility
• Ability of substance to dissolve in water
• Water most often used to extinguish fires
  – Reacts violently with some chemicals (e.g.,
    sulfuric acid, metallic sodium, magnesium)
2
             Corrosivity (1 of 3)
• Ability of a material to cause damage to
  – Skin, eyes, other body parts
  – Clothing, rescue equipment
• Corrosive chemicals should be taken
  seriously
  – Materials require unique response tactics
2
             Corrosivity (2 of 3)
• Two types: Acids and bases
• Defined by pH
  – Acids have pH greater than 7
  – Bases have pH less than 7
  – pH 7 is neutral
• pH < 2.5 or > 12.5 considered strong
2
Corrosivity (3 of 3)




    The pH scale.
2
   Toxic Products of Combustion
• Materials decompose under heat,
  resulting in hazardous chemical
  compounds
• Smoke may not be just smoke!
  – Soot, carbon monoxide, carbon dioxide,
    water vapor, formaldehyde, cyanide
    compounds, nitrogen oxides
2
              Radiation (1 of 2)
• Energy transmitted by electromagnetic
  waves or energetic particles
  – Sources: Sun, soil, X-rays, occupational
    exposures encountered in the field
• Amount absorbed and exposure time
  affect degree of damage
2
     Radiation (2 of 2)




Alpha, beta, and gamma radiation.
2
             Alpha Particles
• Have weight and mass
• Travel less than a few centimeters
• Protect yourself by:
  – Staying several feet from source
  – Using HEPA filter on simple respirator
  – Self-contained breathing apparatus (SCBA)
2
             Beta Particles
• More energetic than alpha particles
• Pose a greater health hazard
  – May redden (erythema) and burn skin
  – May be inhaled; use SCBA
• Can travel 10 to 15 feet in open air
• Are considered ionizing radiation
• Cannot pass through most solid objects
2
          Ionizing Radiation
• Can cause changes in human cells
• Can lead to cancer
• Examples: X-rays, gamma rays
2
       Non-ionizing Radiation
• Comes from electromagnetic waves
• Does not have sufficient energy to change
  human cells
• Examples: Sound waves, radio waves,
  microwaves
2
           Gamma Radiation
• Pure electromagnetic energy
• Most energetic radiation responders may
  encounter
• Passes easily through thick, solid objects
• Form of ionizing radiation; can be deadly
• SCBA will not provide protection
• Neutrons can create gamma radiation
2
        Hazard and Exposure
• Hazard: Material capable of causing harm
• Exposure: Process by which people,
  animals, the environment, and equipment
  come into contact with hazardous material
2
             Contamination
• Residue from released chemical
  – Decontamination: Process of residue removal
• Secondary contamination is transferred
  from source by direct contact
• PPE protects if contact cannot be avoided
  – Does not enable unlimited contact
2
   Weapons of Mass Destruction
          (WMD) (1 of 2)
• Mnemonic for types of damage:
  TRACEMP
  – Thermal
  – Radiological
  – Asphyxiation
  – Chemical
2
 Weapons of Mass Destruction
        (WMD) (2 of 2)
– Etiological (anthrax, plague, smallpox)
– Mechanical
– Psychogenic
2
          Nerve Agents (1 of 3)
• Enter body through lungs or skin
• Disrupt central nervous system
• May cause death or serious impairment
  – Dose absorbed dictates extent of damage
• Examples: Sarin, VX
2
           Nerve Agents (2 of 3)
• Signs/symptoms: “SLUDGEM”
  – Salivation
  – Lacrimation (tearing)
  – Urination
  – Defecation
  – Gastric disturbance
2
           Nerve Agents (3 of 3)
• “SLUDGEM”
 – Emesis (vomiting)
 – Miosis (constriction of the pupil)
2
            Blister Agents (1 of 2)
•   Also known as vesicants
•   Cause blistering of the skin
•   Interact in harmful ways with body
•   Examples: Sulfur mustard, Lewisite
2
Blister Agents (2 of 2)




  Blister agent exposure.
2
                Blood Agents
•   Disrupt oxygen transfer from blood to cells
•   Can be inhaled
•   Can be ingested or absorbed through skin
•   Example: Cyanide compounds
    – Typical signs/symptoms: Vomiting, dizziness,
      watery eyes, deep and rapid breathing
2
             Choking Agents
• Inhibit breathing and are skin irritants
• Extremely irritating odor
• Intended to incapacitate, but may kill
  – May cause pulmonary edema (“dry drowning”)
• Examples: Chlorine, phosgene,
  chloropicrin
2
   Irritants (Riot Control Agents)
• Cause pain and burning sensation
  – Exposed to skin, eyes, mucous membranes
  – Used to briefly incapacitate a person or group
• Least toxic of the WMD groups
  – Decontaminate with water; effects are meant
    to wear off
• Example: Mace
2
              Convulsants
• Cause convulsions or seizures
• Even small exposure can be fatal
• Examples: Sarin, soman, tabun, VX
  – Also organophosphate and carbamate
    pesticides
2
 Harmful Substances’ Routes of
     Entry Into Body (1 of 2)




The four ways a harmful substance can enter the body.
2
     Harmful Substances’ Routes of
         Entry Into Body (2 of 2)
•   Inhalation: Through lungs
•   Absorption: Through skin
•   Ingestion: Through gastrointestinal tract
•   Injection: Through cuts or breaches in skin
2
            Inhalation (1 of 2)
• Hazardous materials/WMD, corrosive
  materials, particles
• SCBA offers excellent protection
• Infectious and contagious organisms also
  hazard
• Example: Anthrax
2
             Inhalation (2 of 2)




• Air-purifying respirators protect against
  certain airborne chemical hazards
  – More comfortable
  – Allow longer work periods
2
                Absorption
• Through skin, eyes, nose, mouth
• Asphyxiants may form, causing
  suffocation
• Some agents are carcinogens
• Aggressive solvents (e.g., paint stripper
  and hydrofluoric acid)
2
                Ingestion
• Chemicals enter body through GI tract
• May occur when rotating out from
  emergency
• After hazardous work, wash before
  drinking/eating
2
                 Injection
• Via cuts, abrasions, open wounds
• Address these before reporting for duty
2
       Chronic Health Hazards
• Appear after long-term exposure to hazard
• Also after multiple short-term exposures
• Target organ effect
  – Example: Asbestosis
2
          Acute Health Effects
• Occur after short, acute exposure
• Examples: Acid burns (sulfuric acid),
  breathing difficulties, and skin irritation
  (formaldehyde, a “sensitizer")
2
                 Toxicity
• Degree to which something is toxic or
  poisonous
• Or, one such substance’s adverse effects
• Lethal dose (LD)
• Lethal concentration (LC)
• OSHA descriptions based on LD and LC
2
            Summary (1 of 3)
• Know chemical and physical properties of
  substances
• Important to making informed response
• Understand physical and chemical
  changes
• Be familiar with characteristics of
  flammable liquids
2
            Summary (2 of 3)
• Understand hazards before responding, to
  minimize potential for exposure
• Avoid contamination whenever possible
• Hazardous substances/WMD enter the
  body through inhalation, ingestion,
  injection, and absorption
2
             Summary (3 of 3)
• May be used as WMD: Nerve agent,
  blister agent, blood agent, choking agent,
  irritant, convulsant
• HEPA filters and SCBA protect lungs
• Chronic health effects occur after years of
  exposure—wear protective gear!

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HazMat Ch02 ppt

  • 2. 2 Objectives (1 of 7) • Describe the following properties: – Boiling point – Chemical reactivity – Corrosivity (pH) – Flammable (explosive) range [lower explosive limit (LEL) and upper explosive limit (UEL)] – Flash point
  • 3. 2 Objectives (2 of 7) – Ignition (autoignition) temperature – Particle size – Persistence – Physical state (solid, liquid, gas) – Radiation (ionizing and non-ionizing) – Specific gravity
  • 4. 2 Objectives (3 of 7) – Toxic products of combustion – Vapor density – Vapor pressure – Water solubility – Physical change and chemical change
  • 5. 2 Objectives (4 of 7) • Describe radiation (non-ionizing and ionizing) as well as the differences among alpha and beta particles, gamma rays, and neutrons.
  • 6. 2 Objectives (5 of 7) • Describe the differences between the following pairs of terms: – Contamination and secondary contamination – Exposure and contamination – Exposure and hazard – Infectious and contagious – Acute and chronic effects – Acute and chronic exposures
  • 7. 2 Objectives (6 of 7) • Describe the following types of weapons of mass destruction: – Nerve agents – Blister agents – Choking agents – Irritants
  • 8. 2 Objectives (7 of 7) • Describe the routes of exposure to hazardous materials for humans
  • 9. 2 Chemical and Physical Properties (1 of 2) • Characteristics of a substance • Important to understand for hazardous substances/WMD • Basis of good decisions on response
  • 10. 2 Chemical and Physical Properties (2 of 2) • Are measurable • They include: – Vapor density – Flammability – Corrosivity – Water reactivity
  • 11. 2 State of Matter (1 of 2) The state of matter identifies the hazard as a solid, liquid, or gas.
  • 12. 2 State of Matter (2 of 2) • Helps predict what substance will do – How will it escape its container? – Why did the container fail? • Influences the incident’s duration – In turn, informs emergency response plan
  • 13. 2 Physical Change • Can occur when chemicals are subjected to – Heat – Cold – Pressure
  • 14. 2 BLEVE • Boiling Liquid/Expanding Vapor Explosion – Pressurized liquefied materials inside closed vessel are exposed to high heat – Results in physical change from liquid to gas • Examples: propane, butane • Expansion ratio: Describes the volume increase that occurs
  • 15. 2 Chemical Reactivity • Also known as chemical change • Ability to transform at molecular level • Usually releases some form of energy • Examples – Steel when it rusts – Wood when it burns
  • 16. 2 “You Are the Responder” Case Study • What physical/chemical changes caused: – The rags to spontaneously ignite? – Failure of the small, propane cylinder? – Fire fighters and residents to experience skin irritation?
  • 17. 2 Critical Characteristics of Flammable Liquids • Flash point • Ignition temperature • Flammable range • Only substances in gaseous or vapor state will combust – Solids and liquids produce vapor, then ignite
  • 18. 2 Flash Point (1 of 3) • Minimum temperature at which ignition results in flash fire • Fire will go out once vapor fuel is consumed
  • 19. 2 Flash Point (2 of 3) Responders should always be mindful of ignition sources at flammable/combustible liquid incidents.
  • 20. 2 Flash Point (3 of 3) • Low flash point = higher ignition temperatures and vapor pressures – Examples: Gasoline, ethyl alcohol, acetone • High flash point = lower ignition temperatures and vapor pressures – Example: #2 grade diesel fuel
  • 21. 2 Fire Point • Temperature at which sustained combustion of vapor occurs • Usually slightly higher than flash point
  • 22. 2 Ignition Temperature • Also known as autoignition temperature • Temperature at which heated fuel ignites and continues to burn • No external ignition source necessary
  • 23. 2 Flammable Range • Concentrations (%) of flammable vapor and air needed for fuel/air mixture to burn • Defined by lower and upper limits: – Lower explosive limit (LEL) – Upper explosive limit (UEL) • More dangerous material has wider range
  • 24. 2 Vapor Pressure (1 of 3) • Pertains to liquids inside closed container • May be expressed in: – Pounds per square inch (PSI) – Atmospheres (atm) – Torr – Millimeters of mercury (mm Hg)
  • 25. 2 Vapor Pressure (2 of 3) The vapors released from the surface of any liquid must be contained if they are to exert pressure.
  • 26. 2 Vapor Pressure (3 of 3) • Influenced by ambient temperature – High temp. → increased vapor pressure – Low temp. → decreased vapor pressure • Causes liquid to evaporate when released – High vapor pressure → evaporates quickly – Low vapor pressure → evaporates slowly
  • 27. 2 Boiling Point (1 of 2) • Liquid continually gives off vapors • Molecules must overcome downward force of atmospheric pressure • If maintained, all liquid will turn into gas
  • 28. 2 Boiling Point (2 of 2) The concept of boiling point versus atmospheric pressure.
  • 29. 2 Vapor Density (1 of 2) • Weight of vapor compared to weight of air – Expressed numerically (e.g., in the MSDS) – Air has set vapor density of 1.0 – Vapor density > 1.0 = heavier; < 1.0 = lighter • Affects gas’ behavior during release • Lighter-than-air gases: “4H MEDIC ANNA”
  • 30. 2 Vapor Density (2 of 2) A. B. A. Vapor density < 1.0 over the cylinder with the gas leak rising upward. B. Vapor density > 1.0 over the cylinder with the heavier- than-air leak.
  • 31. 2 Specific Gravity (1 of 2) • Compares weight of liquid chemical to weight of water • Water has specific gravity of 1.0 • Materials with specific gravity < 1.0 float • Materials with specific gravity > 1.0 sink • Most flammable liquids float on water
  • 32. 2 Specific Gravity (2 of 2) Gasoline will float on water, whereas carbon disulfide will not.
  • 33. 2 Water Solubility • Ability of substance to dissolve in water • Water most often used to extinguish fires – Reacts violently with some chemicals (e.g., sulfuric acid, metallic sodium, magnesium)
  • 34. 2 Corrosivity (1 of 3) • Ability of a material to cause damage to – Skin, eyes, other body parts – Clothing, rescue equipment • Corrosive chemicals should be taken seriously – Materials require unique response tactics
  • 35. 2 Corrosivity (2 of 3) • Two types: Acids and bases • Defined by pH – Acids have pH greater than 7 – Bases have pH less than 7 – pH 7 is neutral • pH < 2.5 or > 12.5 considered strong
  • 36. 2 Corrosivity (3 of 3) The pH scale.
  • 37. 2 Toxic Products of Combustion • Materials decompose under heat, resulting in hazardous chemical compounds • Smoke may not be just smoke! – Soot, carbon monoxide, carbon dioxide, water vapor, formaldehyde, cyanide compounds, nitrogen oxides
  • 38. 2 Radiation (1 of 2) • Energy transmitted by electromagnetic waves or energetic particles – Sources: Sun, soil, X-rays, occupational exposures encountered in the field • Amount absorbed and exposure time affect degree of damage
  • 39. 2 Radiation (2 of 2) Alpha, beta, and gamma radiation.
  • 40. 2 Alpha Particles • Have weight and mass • Travel less than a few centimeters • Protect yourself by: – Staying several feet from source – Using HEPA filter on simple respirator – Self-contained breathing apparatus (SCBA)
  • 41. 2 Beta Particles • More energetic than alpha particles • Pose a greater health hazard – May redden (erythema) and burn skin – May be inhaled; use SCBA • Can travel 10 to 15 feet in open air • Are considered ionizing radiation • Cannot pass through most solid objects
  • 42. 2 Ionizing Radiation • Can cause changes in human cells • Can lead to cancer • Examples: X-rays, gamma rays
  • 43. 2 Non-ionizing Radiation • Comes from electromagnetic waves • Does not have sufficient energy to change human cells • Examples: Sound waves, radio waves, microwaves
  • 44. 2 Gamma Radiation • Pure electromagnetic energy • Most energetic radiation responders may encounter • Passes easily through thick, solid objects • Form of ionizing radiation; can be deadly • SCBA will not provide protection • Neutrons can create gamma radiation
  • 45. 2 Hazard and Exposure • Hazard: Material capable of causing harm • Exposure: Process by which people, animals, the environment, and equipment come into contact with hazardous material
  • 46. 2 Contamination • Residue from released chemical – Decontamination: Process of residue removal • Secondary contamination is transferred from source by direct contact • PPE protects if contact cannot be avoided – Does not enable unlimited contact
  • 47. 2 Weapons of Mass Destruction (WMD) (1 of 2) • Mnemonic for types of damage: TRACEMP – Thermal – Radiological – Asphyxiation – Chemical
  • 48. 2 Weapons of Mass Destruction (WMD) (2 of 2) – Etiological (anthrax, plague, smallpox) – Mechanical – Psychogenic
  • 49. 2 Nerve Agents (1 of 3) • Enter body through lungs or skin • Disrupt central nervous system • May cause death or serious impairment – Dose absorbed dictates extent of damage • Examples: Sarin, VX
  • 50. 2 Nerve Agents (2 of 3) • Signs/symptoms: “SLUDGEM” – Salivation – Lacrimation (tearing) – Urination – Defecation – Gastric disturbance
  • 51. 2 Nerve Agents (3 of 3) • “SLUDGEM” – Emesis (vomiting) – Miosis (constriction of the pupil)
  • 52. 2 Blister Agents (1 of 2) • Also known as vesicants • Cause blistering of the skin • Interact in harmful ways with body • Examples: Sulfur mustard, Lewisite
  • 53. 2 Blister Agents (2 of 2) Blister agent exposure.
  • 54. 2 Blood Agents • Disrupt oxygen transfer from blood to cells • Can be inhaled • Can be ingested or absorbed through skin • Example: Cyanide compounds – Typical signs/symptoms: Vomiting, dizziness, watery eyes, deep and rapid breathing
  • 55. 2 Choking Agents • Inhibit breathing and are skin irritants • Extremely irritating odor • Intended to incapacitate, but may kill – May cause pulmonary edema (“dry drowning”) • Examples: Chlorine, phosgene, chloropicrin
  • 56. 2 Irritants (Riot Control Agents) • Cause pain and burning sensation – Exposed to skin, eyes, mucous membranes – Used to briefly incapacitate a person or group • Least toxic of the WMD groups – Decontaminate with water; effects are meant to wear off • Example: Mace
  • 57. 2 Convulsants • Cause convulsions or seizures • Even small exposure can be fatal • Examples: Sarin, soman, tabun, VX – Also organophosphate and carbamate pesticides
  • 58. 2 Harmful Substances’ Routes of Entry Into Body (1 of 2) The four ways a harmful substance can enter the body.
  • 59. 2 Harmful Substances’ Routes of Entry Into Body (2 of 2) • Inhalation: Through lungs • Absorption: Through skin • Ingestion: Through gastrointestinal tract • Injection: Through cuts or breaches in skin
  • 60. 2 Inhalation (1 of 2) • Hazardous materials/WMD, corrosive materials, particles • SCBA offers excellent protection • Infectious and contagious organisms also hazard • Example: Anthrax
  • 61. 2 Inhalation (2 of 2) • Air-purifying respirators protect against certain airborne chemical hazards – More comfortable – Allow longer work periods
  • 62. 2 Absorption • Through skin, eyes, nose, mouth • Asphyxiants may form, causing suffocation • Some agents are carcinogens • Aggressive solvents (e.g., paint stripper and hydrofluoric acid)
  • 63. 2 Ingestion • Chemicals enter body through GI tract • May occur when rotating out from emergency • After hazardous work, wash before drinking/eating
  • 64. 2 Injection • Via cuts, abrasions, open wounds • Address these before reporting for duty
  • 65. 2 Chronic Health Hazards • Appear after long-term exposure to hazard • Also after multiple short-term exposures • Target organ effect – Example: Asbestosis
  • 66. 2 Acute Health Effects • Occur after short, acute exposure • Examples: Acid burns (sulfuric acid), breathing difficulties, and skin irritation (formaldehyde, a “sensitizer")
  • 67. 2 Toxicity • Degree to which something is toxic or poisonous • Or, one such substance’s adverse effects • Lethal dose (LD) • Lethal concentration (LC) • OSHA descriptions based on LD and LC
  • 68. 2 Summary (1 of 3) • Know chemical and physical properties of substances • Important to making informed response • Understand physical and chemical changes • Be familiar with characteristics of flammable liquids
  • 69. 2 Summary (2 of 3) • Understand hazards before responding, to minimize potential for exposure • Avoid contamination whenever possible • Hazardous substances/WMD enter the body through inhalation, ingestion, injection, and absorption
  • 70. 2 Summary (3 of 3) • May be used as WMD: Nerve agent, blister agent, blood agent, choking agent, irritant, convulsant • HEPA filters and SCBA protect lungs • Chronic health effects occur after years of exposure—wear protective gear!

Editor's Notes

  1. Image: Courtesy of Dr. Saeed Keshavarz/RCCI (Research Center of Chemical Injuries)
  2. Image: Courtesy Sperian Respiratory Protection