9781284042412 Ch02 PPT - Hazmat Level I · 2019. 4. 2. · Responders (1 of 11) • Describe the types of stress that can cause a container to release its contents, the ways in which

Chapter 2

Hazardous Materials: Properties and Effects

Objectives: Awareness Level Personnel (1 of 3)

• Explain the role of Awareness Level personnel during a hazardous materials/WMD incident. (NFPA 4.4.1(2), p. 31–32)

• Describe basic precautions when providing emergency care to victims of hazardous materials/WMD incidents. (NFPA 4.4.1(3)(a), p. 31–38)

Objectives : Awareness Level Personnel (2 of 3)

• Identify common ignition sources found at a hazardous materials/WMD incident. (NFPA 4.4.1(3)(b), p. 22–23)

• Describe some ways in which hazardous materials are harmful to people and the environment. (NFPA 4.4.1(3)(c), p. 31–39)

• Describe the routes of exposure to hazardous materials for humans. (NFPA 4.4.1(3)(d), p. 35–37)

Objectives : Awareness Level Personnel (3 of 3)

• Describe the routes of exposure to hazardous materials for humans. (NFPA 4.4.1(3)(d), p. 35–37)

Objectives: Operations Level Responders (1 of 11)

• Describe the types of stress that can cause a container to release its contents, the ways in which containers can breach, and some of the dispersion patterns created by the release. (NFPA 5.2.3(2)(3)(4)(5), p. 20–22)

• Identify time frames for estimating the duration that hazardous materials/WMD present risk of exposure. (NFPA 5.2.3(6), p. 37–39)


• Describe the following properties:– Boiling point (NFPA 5.2.3(1)(a)(i), p. 25)– Chemical reactivity (NFPA 5.2.3(1)(a)(ii), p.

21)– Corrosivity (pH) (NFPA 5.2.3(1)(a)(iii), p. 27)– Flammable (explosive) range (lower explosive

limit [LEL] and upper explosive limit [UEL]) (NFPA 5.2.3(1)(a)(iv), p. 23–24)


• Describe the following properties (cont’d):– Flash point (NFPA 5.2.3(1)(a)(v), p. 22–23)– Ignition (autoignition) temperature (NFPA

5.2.3(1)(a)(vi), p. 23)– Particle size (NFPA 5.2.3(1)(a)(vii), p. 36–37)– Persistence (NFPA 5.2.3(1)(a)(viii), p. 34)


• Describe the following properties (cont’d):– Physical state (solid, liquid, gas) (NFPA

5.2.3(1)(a)(ix), p. 20)– Radiation (ionizing and non-ionizing) (NFPA

5.2.3(1)(a)(x), p. 29)– Specific gravity (NFPA 5.2.3(1)(a)(xi), p. 26)– Toxic products of combustion (NFPA

5.2.3(1)(a)(xii), p. 28)


• Describe the following properties (cont’d):– Vapor density (NFPA 5.2.3(1)(a)(xiii), p. 25)– Vapor pressure (NFPA 5.2.3(1)(a)(xiv), p. 24)– Water solubility (NFPA 5.2.3(1)(a)(xv), p. 27)– Physical change and chemical change (NFPA

5.2.3(1)(a)(xvi), p. 20–22)


• Describe radiation (non-ionizing and ionizing) as well as the difference between alpha and beta particles, gamma rays, and neutrons. (NFPA 5.2.2(8), 5.2.3, p. 29–31)

• Describe the differences between the following pairs of terms:– Contamination and secondary contamination

(NFPA 5.2.3(1)(b)(i), p. 31–32)


• Describe the differences between the following pairs of terms (cont’d):– Exposure and contamination (NFPA

5.2.3(1)(b)(ii), p. 31–32)– Exposure and hazard (NFPA 5.2.3(1)(b)(iii), p. 31)– Infectious and contagious (NFPA 5.2.3(1)(b)(iv),

p. 36)– Acute and chronic effects (NFPA 5.2.3(1)(b)(v), p.

37–38)– Acute and chronic exposures (NFPA

5.2.3(1)(b)(vi), p. 37–38)


• Describe the following types of weapons of mass destruction:– Blood agents (NFPA 5.2.3(9)(a), p. 34)– Biological agents and biological toxins (NFPA

5.2.3(9)(b), p. 32)– Choking agents (NFPA 5.2.3(9)(c), p. 35)– Irritants (riot control agents) (NFPA

5.2.3(9)(d), p. 35)


• Describe the following types of weapons of mass destruction (cont’d):– Nerve agents (NFPA 5.2.3(9)(e), p. 32–34)– Radiological materials (NFPA 5.2.3(9)(f), p. 32)– Vesicants (blister agents) (NFPA 5.2.3(9)(g), p.

34)• Describe the health and physical hazards of

exposure to hazardous materials. (NFPA 5.2.3(7), p. 35–37)


• Describe the health hazards associated with the following:– Alpha, beta, gamma, and neutron radiation

(NFPA 5.2.3(8)(a), p. 29–31)– Asphyxiant (NFPA 5.2.3(8)(b), p. 37)– Carcinogen (NFPA 5.2.3(8)(c), p. 37)– Convulsant (NFPA 5.2.3(8)(d), p. 35)


• Describe the health hazards associated with the following (cont’d):– Corrosive (NFPA 5.2.3(8)(e), p. 27–28)– Highly toxic (NFPA 5.2.3(8)(f), p. 38)– Irritant (NFPA 5.2.3(8)(g), p. 35)– Sensitizer/allergen (NFPA 5.2.3(8)(h), p. 38)– Target organ effects (NFPA 5.2.3(8)(i), p. 37–

38)– Toxic (NFPA 5.2.3(8)(j), p. 38)

Chemical and Physical Properties

• Characteristics of a substance• Important to understand for hazardous

substances/WMD• Basis of good decisions during response

Examples of Chemical and Physical Properties

• Vapor density• Flammability• Corrosivity• Water reactivity

Responding Safely

• Not necessary to be a chemist– Careful observation– Emergency response plan and/or SOP – Interpreting visual clues

Physical and Chemical Changes(1 of 2)

• First step: identify the state of matter– Solid, liquid, or gas


• What will the substance do if it escapes from containment vessel?

• Ways containers breach: disintegration, runaway cracking, closures opening, punctures, tears


Photos Courtesy of Rob Schnepp


• Determine how the substance will escape.• Dispersion patterns: cloud, stream, plume, pool,

hemispheric release, cone, and irregular dispersion

Physical and Chemical Changes (8 of 8)

• Determine duration of event.• Chemicals undergo physical change when

subjected to: – Heat – Cold – Pressure

Physical and Chemical (1 of 2)• Despite change,

chemical make-up (H2O) remains the same.

• BLEVE (Boiling Liquid /Expanding Vapor Explosion)

Courtesy of Rob Schnepp

Physical and Chemical (2 of 2)

• Pressurized liquefied materials inside a closed vessel exposed to high heat

• Substance changed from liquid to gas• Example: propane and butane

Expansion Ratio

• The volume increase that occurs when a liquid changes to a gas– Propane has an expansion ratio of 270 to 1.– For every 1 volume of liquid propane, 270

times that amount of propane exists as vapor.

Chemical Reactivity

• The ability of a substance to undergo a transformation at the molecular level– Usually with a release of some form of energy– Physical change = change in state – Chemical change = alteration of the chemical

nature of the material– Examples: steel when it rusts and wood when

it burns

You are the Responder Case Study• Assume the landscape company owner wadded

up some rags soaked with linseed oil and left them in the corner of the shed.– Rags ignited spontaneously. (Chemical change:

Linseed oil generates heat as it decomposes, comes into contact with oxygen, and ignites)

– Fire caused failure of propane cylinder. (Chemical change: BLEVE)

– Fire melted fusible plug on a chlorine cylinder, causing a release of chlorine gas. (Chemical change: Gas mixes with moisture in air, forms acidic mist, which comes into contact with fire fighters’ skin and eyes to cause irritation.)

Critical Characteristics of Flammable Liquids

• Flash point • Ignition temperature • Flammable range • Only substances in a gaseous or vapor

state will combust.

Flash Point (1 of 5)

• Minimum temperature at which vapors from a liquid or solid will result in a flash fire when ignited

• Ignition source examples:– Flame– Electrical equipment– Lightning – Static electricity


• Involves only vapor phase of liquid• Will go out once vapor fuel is consumed• Common substances with low flash points:

– Gasoline– Ethyl alcohol– Acetone


• #2 grade diesel fuel has a high flash point, resulting in lower ignition temperature and lower vapor pressure.

• When temperature increases, so does production of vapor by flammable liquids.

Fire Point

• Temperature at which sustained combustion of vapor will occur

• Usually only slightly higher than the flash point for most materials

Ignition Temperature (1 of 2)

• Autoignition temperature• Minimum temperature at which a fuel,

when heated, will ignite in air and continue to burn

• No external ignition source necessary

Ignition Temperature (2 of 2)

• Example: pan full of cooking oil on the stove, left unattended on a burner set on high– Will ignite once the oil is heated past its

ignition temperature– Common cause of stove fires

Flammable Range (1 of 3)

• Expression of fuel/air mixture that reflects an amount of flammable vapor mixed with a given volume of air

• Boundaries necessary to burn– Lower explosive limit (LEL)– Upper explosive limit (UEL)


• Example: Gasoline – LEL is 1.4% – UEL is 7.6%

• The wider the flammable range, the more dangerous the material.

Vapor Pressure (1 of 4)• Applies to liquids held

inside any type of closed container

Vapor Pressure (2 of 4)

• All liquids develop pressure in the airspace between the top of the liquid and the container.

• Vapors released from the surface of any liquid must be contained if they are to exert pressure. – Example: carbonated beverages


• Liquids with high vapor pressures evaporate much more quickly than liquids with low vapor pressures.


• Expressed in:– Pounds per square inch (psi)– Atmospheres (atm)– Torr– Millimeters of mercury (mm Hg)– Bar

• 14.7 psi = 1 atm = 760 torr = 760 mm Hg = 1 bar

Boiling Point (1 of 2)

• Temperature at which a liquid will continually give off vapors in sustained amounts

• If held at that temperature long enough, will turn completely into a gas

Boiling Point (2 of 2)• At water’s boiling

point (212°F), the water molecules have enough kinetic energy to overcome the downward force of atmospheric pressure.

Vapor Density (1 of 4)• Weight of an airborne

concentration of a vapor or gas, compared to an equal volume of dry air

Vapor Density (2 of 4)

• Air has a set vapor density of 1.0.• Gases with vapor density > 1.0 are heavier

than air. • Gases with vapor density < 1.0 are lighter

than air.• Affects where the gas goes when released


• 4H MEDIC ANNA:– H: Hydrogen– H: Helium– H: Hydrogen cyanide– H: Hydrogen fluoride– M: Methane– E: Ethylene– D: Diborane


• 4H MEDIC ANNA (cont’d):– I: Illuminating gas (methane/ethane mixture)– C: Carbon monoxide– A: Ammonia– N: Neon– N: Nitrogen– A: Acetylene

Specific Gravity (1 of 4)

• Compares weight of liquid chemical to weight of water

• Is to liquids what vapor pressure is to gases and vapors

• Water has a specific gravity of 1.0.

Specific Gravity (2 of 4)• Materials with a

specific gravity less than 1.0 float.


Specific Gravity (3 of 4)• Materials with a

specific gravity greater than 1.0 sink.

• Most flammable liquids float.


Specific Gravity (4 of 4)

• Examples: – Gasoline – Diesel fuel – Motor oil – Benzene

Water Solubility

• Ability of a substance to dissolve in water• Water is the predominant agent used to

extinguish fire.– May not always be the best and safest choice– Can react violently with certain chemicals

• Fog streams may knock down vapor clouds.

Corrosivity (1 of 6)

• Ability of a material to cause damage to skin, eyes, and other parts of the body

• Technical definition: destruction or irreversible damage to living tissue at the site of contact

• Also damaging to clothing, rescue equipment, other physical objects


• Complex group of chemicals • Tens of thousands of corrosive chemicals • Acids and bases

Corrosivity (4 of 6)• Acids and bases:

– Measured by pH – Specialized pH test

paper – Acids have pH less

than 7 (sulfuric, hydrochloric)

© Jones & Bartlett Learning. Photographed by Glen E. Ellman

Corrosivity (5 of 6)• Bases have pH

greater than 7 (sodium and potassium hydroxide).

• pH 7 is neutral.

© Jones & Bartlett Learning. Photographed by Glen E. Ellman


• pH values of 2.5 or less and of 12.5 or more are considered strong.

• Strong corrosives react more aggressively with metals, skin, other chemicals, water.

• Awareness operations level: corrosives are complicated and tactics needed may be outside scope of responsibilities.

Toxic Products of Combustion (1 of 2)

• Hazardous chemical compounds released when a material decomposes under heat

• Combustion generates by-products.• Smoke

– Toxic gases may be liberated during a residential structure fire.

Toxic Products of Combustion (2 of 2)

• Fire smoke includes soot, carbon monoxide, carbon dioxide, water vapor, formaldehyde, cyanide compounds, and oxides of nitrogen.– Toxic even in small doses– Cause difficulty with oxygen transport, tissue

asphyxiation, eye or lung irritation, or pulmonary edema

Radiation (1 of 5)• Energy transmitted through space in the

form of electromagnetic waves or energetic particles

• Radiation sources:– Sun – Soil– X-rays– Occupational exposures encountered in the

field

Radiation (2 of 5)

• Health hazards posed determined by– Amount of radiation absorbed by your body– Exposure time to the radiation

• Periodic table of elements

Radiation (3 of 5)

Radiation (4 of 5)

• Atoms: made of protons, neutrons, and electrons

• Radioactive isotopes• Radioactivity is the process by which

unstable atoms (isotopes) of an element decay to a different state and emit or radiate excess energy.

Radiation (5 of 5)• Combination of alpha,

beta, and gamma radiation

• Responders can wear small radiation detectors on turnout gear.

Alpha Particles

• Have weight and mass• Cannot travel far—less than a few

centimeters• Stay several feet from the source and

wear a HEPA filter on a simple respirator or SCBA.

Beta Particles

• More energetic than alpha particles• Pose a greater health hazard• Can travel 10 to 15 feet in open air• Considered ionizing radiation

Ionizing Radiation

• Can cause changes in human cells• Possibly leads to cancer• Examples: X-rays and gamma rays

Non-ionizing Radiation

• Comes from electromagnetic waves• No sufficient energy to change human

cells• Examples: sound waves, radio waves, and

microwaves

Effect of Beta Particles

• May redden and burn skin• Damage to tissue when inhaled• Solid objects provide protection. • SCBA should provide respiratory

protection.

Gamma Radiation (1 of 2)

• Pure electromagnetic energy• Most energetic radiation that responders

may encounter– No mass – No electrical charge – Travels at the speed of light

Gamma Radiation (2 of 2)

• Passes easily through thick, solid objects• Ionizing radiation • Can be deadly• Neutrons can create gamma radiation.• SCBA will not provide protection.

Neutrons

• Penetrating particles found in the nucleus of the atom

• Exposure can create radiation.

Hazard and Exposure

• Observe the scene and establish a safe perimeter.

• A hazard is a material capable of causing harm.

• Exposure is the process by which people, animals, the environment, and equipment are subjected to or come into contact with a hazardous material.

Contamination

• The residue of a released chemical• Decontamination: the process of removing

the residue resulting from a chemical release

Secondary Contamination• Cross-contamination• Occurs when a

person or object transfers the contamination, or the source of contamination, to another person or object by direct contact


PPE

• Misperception: PPE is worn to enable you to contact the product at will.

• Fact: PPE is worn to protect you in the event that you cannot avoid product contact.

Weapons of Mass Destruction (1 of 2)

• Seven types of damage (TRACEMP):– T: Thermal– R: Radiological– A: Asphyxiation

Weapons of Mass Destruction (2 of 2)

• Seven types of damage (TRACEMP) (cont’d):– C: Chemical– E: Etiological (anthrax, plague, smallpox)– M: Mechanical– P: Psychogenic

Nerve Agents (1 of 3)

• Enter the body through the lungs or skin• Disrupt the central nervous system• May cause serious impairment or death• Example: sarin


• Signs/symptoms: “SLUDGEM”– S: Salivation– L: Lacrimation– U: Urination– D: Defecation– G: Gastric disturbance


• Signs/symptoms: “SLUDGEM” (cont’d)– E: Emesis (vomiting) – M: Miosis (constriction of the pupil)

• Example: VX (the most toxic of weapons-grade nerve agents)

Blister Agents (1 of 5)

• Vesicants• Ability to cause blistering of the skin• Common agents: sulfur mustard and

lewisite


• Sulfur mustard – First used in WWI– Liquid state– Colorless and odorless if pure; brownish with

garlic/onion smell when mixed– Signs and symptoms 2 to 24 hours after

exposure

Blister Agents (3 of 5)• Sulfur mustard

(cont’d) – Injuries similar to

second- and third-degree burns

– Inhalation exposure can lead to respiratory function impairment

Courtesy of Dr. Saeed Keshavarz/RCCI (Research Center of Chemical Injuries)


• Lewisite – Many same characteristics of sulfur mustard– Arsenic – Exposure symptoms may mimic arsenic

poisoning.– Skin exposure causes immediate pain.


• Lewisite (cont’d) – Chemical warfare agent– High concentrations lead to:

• Convulsions • Inability to breathe • Loss of consciousness• Death

Blood Agents (1 of 2)

• Chemicals that interfere with the transfer of oxygen from the blood to the cells

• Inhaled, ingested, or absorbed through the skin

• Examples: cyanide compounds

Blood Agents (2 of 2)

• Typical signs/symptoms of exposure: vomiting, dizziness, watery eyes, deep and rapid breathing

• High concentrations lead to convulsions, inability to breathe, loss of consciousness, and death.

Choking Agents (1 of 2)

• Inhibit breathing• Extremely irritating odor• Intended to incapacitate, but may kill or

cause serious injuries

Choking Agents (2 of 2)

• Examples:– Chlorine – Phosgene – Chloropicrin

• Act as skin irritants; can cause significant burning in high concentrations

Irritants

• Cause pain and burning sensation when exposed to skin, eyes, and mucous membranes

• Example: mace• Used to temporarily incapacitate a person

or a group of people• Least toxic of the WMD groups

Convulsants (1 of 2)

• Cause convulsions or seizures when absorbed by the body

• Examples: sarin, soman, tabun, VX, and organophosphate and carbamatepesticides

Convulsants (2 of 2)

• Interfere with central nervous system and disrupt normal transmission of neuromuscular impulses

• Some pesticides function as convulsants• Fatal in small exposures

Routes of Entry (1 of 2)

• Inhalation: Through the lungs• Absorption: Permeating the skin• Ingestion: Gastrointestinal tract• Injection: Cuts or other breaches in the

skin

Routes of Entry (2 of 2)

Inhalation (1 of 6)

• Exposures occur when harmful substances are brought into the body through the respiratory system.– Corrosive materials – Solvent vapors– Superheated air– Infectious and contagious organisms

Inhalation (2 of 6)• SCBA is most

important piece of PPE for fire fighters.

• Full-face and half-face air purifying respirators (APRs)

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Inhalation (3 of 6)

• SCBA and APRs – OSHA: Any work environment containing less

than 19.5% oxygen requires the use of an SCBA or supplied air respirator

– More comfortable– Allow for longer work period

Inhalation (4 of 6)

• Anticipated particle size of containment may dictate the level of respiratory protection

Inhalation (5 of 6)

• Anthrax requires SCBA or full-face APR with P100 filtration– Infectious: Organism capable of causing an

illness– Contagious: Capable of being passed along

to another person

Inhalation (6 of 6)

• Particle size determines where inspired contaminants will end up

Absorption (1 of 2)

• Process by which substances travel through the body tissues until they reach the bloodstream

• Occurs through skin, eyes, nose, mouth, intestinal tract

• The body may produce an asphyxiant as a by-product.

Absorption (2 of 2)

• Asphyxiants prevent the body from using oxygen.

• Some agents are carcinogens. • Aggressive solvents are readily absorbed.• Evaluate the possibility of chemical

contact and determine if firefighting turnout gear is sufficient.

Ingestion

• Chemicals are brought into the body through the gastrointestinal tract

• May occur when rotating out from an emergency response and not taking the time to wash up prior to eating or drinking

Injection

• Chemicals enter the body through open cuts and abrasions

• Address cuts or open wounds before reporting for duty.– If significant, you may be excluded from

contained environments.– Open wounds act as direct portal to the

bloodstream.

Chronic Health Hazards

• Appear after long-term, or chronic, exposure to a hazardous substance

• Also appear after multiple short-term exposures

• Target organ effect – Example: Chronic asbestosis exposures

target the lungs

Acute Health Effects• Occur after relatively short-term, or acute,

exposure• Produce observable conditions, such as

eye irritation, coughing, dizziness, and skin burns

• Examples: – Acid burns from sulfuric acid – Breathing difficulties and skin irritation from

exposure to formaldehyde

Toxicity (1 of 4)

• A measure of the degree to which something is toxic or poisonous– Substance’s adverse effects

• Lethal dose (LD)• Lethal concentration (LC) • OSHA descriptions are based on the LD

and LC.

Toxicity (2 of 4)

• The LD is the lowest dosage per unit of body weight (mg/kgl) of a substance known to have resulted in a fatality.

• Median LD (LD50) • LDhi• LClo

Toxicity (3 of 4)

• OSHA 29 CFR 1910.1200 defines toxic as:– Chemical with an LD50 between 50 and 500

mg/kg via oral administration– Chemical with an LD50 between 200 and 1000

mg/kg via continuous contact with bare skin for 24 hours

– Chemical with an LC50 in air between 200 and 2000 ppm via continuous inhalation for 1 hour

Toxicity (4 of 4)

• OSHA 29 CFR 1910.1200 defines highly toxic as:– Chemical with an LD50 of 50 mg/kg or less via

oral administration– Chemical with an LD50 of 200 mg/kg or less

via continuous contact with bare skin for 24 hours

– Chemical with an LC50 in air of 200 ppm or less via continuous inhalation for 1 hour

Summary (1 of 7)• The most fundamental of all actions is the

ability to observe the scene and understand the problem you are facing. Think before you act—it could save your life!

• An important first step in understanding the hazards of any chemical is identifying the state of matter and defining whether the substance is a solid, liquid, or gas.

Summary (2 of 7)

• A critical step in comprehending the nature of the release is identifying the reason(s) why the containment vessel failed.

Summary (3 of 7)

• Chemical change is not the same thing as physical change. Physical change is a change in state; chemical change describes the ability of a substance to undergo a transformation at the molecular level, usually with a release of some form of energy.

Summary (4 of 7)

• There are many critical characteristics of flammable liquids, and you should be familiar with each of them.

• When responders respond to hazardous materials incidents, they must fully understand the hazards to minimize the potential for exposure.

Summary (5 of 7)• Avoid contamination wherever possible—it

will reduce the likelihood of harmful exposures.

• Chemicals can enter the body in four ways: inhalation, absorption, ingestion, and injection.

• Nerve agents, blister agents, blood agents, choking agents, irritants, and convulsants are examples of hazardous materials that may be used as WMD.

Summary (6 of 7)

• Irritants such as mace cause immediate irritation of the skin, eyes, and mucous membranes.

• Equipment such as APR and SCBA can protect lungs from select particulates such as smoke, dust, and fumes.

Summary (7 of 7)

• Chronic health effects may occur after years of exposure to hazardous materials. Wear all protective gear to minimize the impacts of repeated exposures.

Documents

9781284042412 Ch02 PPT - Hazmat Level I · 2019. 4. 2. · Responders (1 of 11) • Describe the types of stress that can cause a container to release its contents, the ways in which