2 Chemistry & Toxicology Definitions and terminology
3 ObjectivesTo understand basic chemistry and toxicology terms (29 CFR (q) (6) (iii))To understand the 8 UN hazard classesTo demonstrate understanding by relating terms to decisions made on scene
4 Properties of Flammable Materials Flash point - the temperature at which a fuel will give off enough vapors to flash near the surface but not continue to burnFire point - the temperature at which a fuel will give off enough vapors to support combustionDEMO:Light Gasoline and diesel
5 More Definitions... Agency Flammable Combustible DOT <141°F OSHA<100°F>100°FNFPAEPA<140°F
6 Gasoline? Diesel? Auto-ignition Temperature The minimum temperature to which a fuel in air must be heated to start self-sustained combustion without a separate ignition source.Gasoline?800oFDiesel?400oF
7 Flammable Range}The concentration of fuel in air required to burn. It falls between the LEL and UEL.The wider the flammable range the more dangerous the fuel.Too LeanLELUEL}Too RichGAS
8 Vapor PressureThe pressure molecules apply towards the atmosphere while trying to escape a liquid surface (evaporate).Vapor molecules are always over a liquid, if the Vp is higher than the atmospheric pressure, the liquid will evaporate.Boiling point is when a liquid’s Vp is equal to the atmospheric pressure.Demo boiling water at room temp.Gasoline
9 Specific GravityThe specific gravity of a product is the weight of the product compared to the weight of water(Water = 1)Examples:GasolineParathion 1.27DEMO:Show vial with gasoline on water
10 Vapor DensityVapor density is the weight of the product compared to air(Air = 1)Examples:Gasoline 3.5Methane 0.55
11 Crossing state linesBoiling pointMelting pointSublimation
12 Mixing substancesMiscibility: The ability for two substances to mix so that they will not separate into phases. Alcohol into water, acid into waterSolubility: A measure of how much solute will dissolve into a solvent. Usually refers to water when possible, but obviously not everything dissolves in water.
13 Classes 1 – 9 UN Hazard Classes Color indicates hazard Symbol of the hazardCenter may have words or UN ID numberUN hazard class
14 Explosives Rate What is the difference between an explosion and rust? Detonation exceeds the sound barrier and deflagration is slower than the sound barrier.
15 Gases Burning state for all matter May be kept under high pressure Can be liquefied by pressure or temperature
16 Flammable Liquids One of the most common commodities transported If gasoline and diesel are carried together, it can be placarded with the worst hazardCarried in MC-306 and MC-307Toxicity is also a hazard
17 Flammable SolidsSome are water reactive such as sodium or calcium carbide.Some are pyrophoric (reacts with air) such as phosphorus.
18 Oxidizers Bring their own oxygen to the table Make ordinary combustible highly flammableOrganic peroxides can breakdown into explosive crystalsMSST: Maximum safe storage temperatureSADT: Self accelerating decomposition temperature
19 Poisons These are toxic to life May be marked: Marine pollutant Keep from food stuffsInhalation hazardTable II (49 CFR) commodity, meaning it is placarded for any amount being transported
20 RadioactiveAlpha radiation (α): About the size of a proton, its heavy and doesn’t travel far. Can be stopped by paper.Beta radiation (β): About the size of an electron, travels farther than α but is still stopped by skinGamma (γ): Not a particle, it’s a wave. Travels through the body. Thick concrete, lead, or water can stop it.TDS: Time, Distance, Shielding are your only protections from radiation.
21 Corrosives 1 7 14 base acid water pH is a measure of the H+ ion concentration. A pH of 7 is 10,000,000 times weaker an acid that a pH of 1.Neutralization is an option for mitigation and decon for incidents involving corrosives.
24 Miscellaneous Whatever didn’t fit in the other drawers. Often these are dusts, ores, or hazardous wastes (n.o.s. – not otherwise specified)
25 ToxicityDose response: The relationship between the amount of a substance taken in over time and its effect.BACBACTimeTimeWhich type of consumption will have the worst acute effect? How does this work with chronic effects?
28 EffectsCarcinogen: Cancer causing. “100% chance that being a lab rat causes cancer.” –unknownMutagen: DNA changing, will effect future offspring.Teratogen: Effects a fetus.
29 MSDS (a) Physical and chemical characteristics (b) Physical hazards of the material(c) Health hazards of the material(d) Signs and symptoms of exposure(e) Routes of entry(f) Permissible exposure limits(g) Responsible party contact(h) Precautions for safe handling (including hygiene practices, protective measures, procedures for cleanup of spills or leaks)(i) Applicable control measures including personal protective equipment(j) Emergency and first aid procedures
30 Pesticides (a) Name of pesticide (b) Signal word CautionWarningDanger(c) Precautionary statement(d) Hazard statement(e) Active ingredient