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Unit 2.2 Physical and Chemical Properties. Objectives. Match important physical and chemical properties to their effects on the chemical and container Identify the difference between exposure and contamination Determine the appropriate DOT class of the product. Physical/Chemical Properties.
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Unit 2.2 Physical and Chemical Properties
Objectives • Match important physical and chemical properties to their effects on the chemical and container • Identify the difference between exposure and contamination • Determine the appropriate DOT class of the product
Physical/Chemical Properties Physical • State • Phase changes • Vapor pressure • Specific gravity • Vapor density • Solubility Chemical • Flammability • Reactivity • Toxicity • Radioactivity
Common Info Sources • North American Emergency Response Guide Book (NAERG) • NIOSH Pocket Guide to Chemical Hazards • Material Safety Data Sheets (MSDS)
Material Safety Data Sheets • Nine basic sections • Various designs • Some of better quality
Ceiling Amount STEL TWA 1 2 3 4 5 6 7 8 Duration (hrs) Exposure Limits
Vapor Pressure Atmospheric Pressure 14.7 p.s.i. or 760 mm/Hg Low Vapor Pressure High Vapor Pressure
Water = 1 Specific Gravity less than 1 Specific Gravity greater than 1 Water = 1 Specific Gravity
Physical Properties (cont.) • Vapor density • Comparison of the weight of a vapor to that of air being assigned the value of 1 • Solubility/miscibility • The ability of a substance (solute) to blend uniformly with another (solvent) • Solubility applied to a solid in liquid • Miscibility applied to a liquid or gas in a liquid
Most Common Types(Transformation must be considered) Air (A) Water (W) Surface (SF) Sub-Surface (SSF) Gas (G) G/A Liquid (L) L/W L/SF L/SSF Solid (S) S/SF Spill Types • Physical properties determine spill types
FUEL (Reducing Agent) OXYGEN (Oxidizer) HEAT (Energy) The Fire Triangle
Flash Point • “The temperature at which a liquid or volatile solid gives off vapors sufficient to form an ignitable mixture near the surface…” (NFPA) • Remember, volatility is a product of vapor pressure
L.E.L. U.E.L. Lean Rich Range 0 10 20 30 40 50 60 70 80 90 100 Flammable Range
Propane 2.2 - 9.5 % 0 10 20 30 40 50 60 70 80 90 100 Acetylene 2.5 - 100 % 0 10 20 30 40 50 60 70 80 90 100 Examples of Flammable Range
Other Flammable Hazards • Ignition temperature • Boiling Liquid Expanding Vapor Explosions (BLEVE) • Boil-over • Heavy fuels • Water in the bottom of the storage tank • Thermocline development during fire
Other Flammable Hazards • Pyrophoric • Hydrophoric • Flammable solids
Health Hazards • Routes of exposure • Local vs. systemic effects • Dose response relationship • Influences of toxicity
BASE (ALKALINE) ACID 0 7 14 2 12.5 pH and Corrosives
Reactions • Rate of reactions • Quantity, concentration, temperature and pressure • Explosives • Fuel, oxidizer, energy, pressure • Incompatibilities
A B 1 Acids Bases (Alkaline) 2 Metals Corrosives 3 Group 1/Hydrophoric Alcohol/Water 4 Oxidizers Reducers 5 Cyanides/Sulfides Acids EPA Table of Incompatibilities
Special Information • Special handling • Special packaging • Disposal procedures • Environmental information
Radioactive Hazards • Ionizing radiation • Common sources • Natural • Industrial • Medical • Agricultural • Special nuclear materials
Types of Ionizing Radiation • Alpha particle • Beta particle • Gamma emission • X-ray • Neutron particles
Radiological Exposure • Standard unit of measure • REM (Radiation Equivalence in Man) • Sv (Seivert) internationally • 1 Sv = 100 REM • 1 REM = 1,000 mREM (milli REM) • 1 mREM = 1,000 REM (micro REM)
Exposure Limits • Dose vs. dose rate • Total dose = dose rate x duration • Action levels • Normal background = 8 to 16 R/hr • All actions = 5 REM (5,000 mREM) • Valuable/critical property = 10 REM (10,000 mREM) • Life saving = 25 REM (25,000 mREM) • Any greater exposure must be voluntary • TD(low) 100 REM, LD(50) 500 REM
Hazard Classes and Divisions 1 Explosives 1.1 - Mass detonation 1.2 - Projectile 1.3 - Fire hazard 1.4 - No blast hazard 1.5 - Blasting agent 1.6 - Very insensitive 2 Gases 2.1 - Flammable 2.2 - Non-flammable 2.3 - Poisonous 3 Flammable liquid 3.1 - Flash point over 140 °F 3.2 - Flash point less than 140 °F 4 Flammable solids 4.1 - Flammable solid 4.2 - Spontaneous/pyrophoric 4.3 - Dangerous when wet 5 Oxidizers 5.1 - Oxidizers 5.2 - Organic peroxides
Hazard Classes and Divisions 6 Poisons 6.1 - Poisons 6.2 - Infectious substances 7 Radioactive 8 Corrosives 9 Miscellaneous
Summary • Physical properties • Chemical properties • Common references • NAERG • NIOSH Pocket Guide • MSDS
Activity 2.2 Assessing Physical and Chemical Properties