Chemical Hazards Afshin Fassihi Safety and Personal Protection Committee of Isfahan Faculty of Pharm

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Chemical HazardsAfshin FassihiSafety and
Personal Protection Committee of Isfahan
Faculty of Pharmacy
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Session Objectives

• To understand the hazards associated with
  chemicals
• To understand how to control these hazards in the
  workplace
• To know the hazardous signs, in order to be able
  to identify and correctly handle a particular
  chemical or material
• To do the best practices in the Lab safe
  practices while working with chemicals

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Chemical Hazards Classification

• Chemical Hazards According to WHIMS (Workplace
  Hazardous Materials Information System)
• Class A
• Compressed Gas
• Any Hazardous Material that is contained under
  pressure including
• compressed gas,
• dissolved gas, or
• liquefied gas
• which are flammable, inflammable or poisonous.
  

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Chemical Hazards Classification

• Compressed Gas Cylinders
• Store and transport with safety cap
• DO NOT store fuel gas with oxygen
• Secure in an upright position
• Use in a well ventilated area
• Use the proper type of regulator
• Empty cylinders are marked EMPTY
• Check hoses, tubing, and regulators daily

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Chemical Hazards Classification

• Class B
• Flammable and Combustible Material
• Flammable Gases
• Flammable and Combustible Liquids
• Flammable Solids
• Flammable Aerosols
• Reactive Flammable Material

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Chemical Hazards Classification

• The determining factor in whether a liquid is
  flammable or combustible is its flashpoint.
• Flashpoint
• The minimum temperature at which a liquid
  gives off enough vapor within a test vessel in
  sufficient concentration to form an ignitable
  mixture with air near the surface of the liquid.
• A chemicals flashpoint is listed on the MSDS
  under the Fire and Explosion section.

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Chemical Hazards Classification

• Flammable Liquids
• Any liquid having a flashpoint below 100o F
  (37.8o C) or lower.
• Combustible Liquids
• Any liquid having a flashpoint at or above 100o F
  (37.8o C).
• Ignition Sources
• Naked Flames
  Electrical Spark
• Impact Spark Static
  Electricity
• Hot Surfaces

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Chemical Hazards Classification

• Examples of Flammable Liquids
• Liquid Flash Point
  (oC)
• Diethyl Ether 42.8
• Acetone 17.8
• n-Butanol 2.2
• Isopropanol 7.2
• Ethanol 13.0
• Methanol 7.2
• MEK 5.0
• Xylene 26.1
• Toluene 7.2
• Gasoline -45.5

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Chemical Hazards Classification

• Flammable Materials
• How to Handle Flammable Materials?
• Store liquids in Flammable Storage Cabinet
• Eliminatee flames, static electricity, sparks
  from electrical circuits
• Decant in large quantities in fume hood with good
  ventilation
• Keep away from heat and direct sunlight
• Dispose spent flammable liquids in a proper
  manner

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Chemical Hazards Classification

• Auto-Ignition
• Temperature required to cause self ignition of
  flammable liquids / vapours
• Typically greater than 400 degrees C
• Generally in open conditions (workplace)
  temperatures required for auto-ignition are much
  higher

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Chemical Hazards Classification

• Class C
• Oxidizing Material
• Oxidizers
• Chemicals which react violently when exposed to
  air or water
• Oxidizers cause other substances to burn more
  easily by giving oxygen or some other oxidizing
  substances.
• Organic Peroxides

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Chemical Hazards Classification

• Oxidizers
• Chlorates, Nitric Acid, Peroxides, Permanganates,
  Perchlorates, Nitrites, Nitrates
• Easily oxidize metal powders, organic materials
• Keep minimum quantities in lab
• Segregate from other materials, such as organic
  solvents
• PPE and/or explosion barriers may be require

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Chemical Hazards Classification

• Organic Peroxides
• Some are very unstable
• Sensitive to heat, friction, impact, sparks,
  light
• Use minimum quantities in lab
• NEVER replace unused peroxides into original
  container
• NEVER use a metal spatula to handle peroxides
• Refrigerate to minimize decomposition

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Chemical Hazards Classification

• Peroxide Formers
• Have caused several severe laboratory explosions
• Contributing Factors Oxygen, Light, Storage Time
• Visual Identifiers Crystals, Floating wisp-like
  structures
• Date and Dispose of within 1 year

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Chemical Hazards Classification

• Common Chemicals forming Peroxides
• Tetrahydrofuran
• Diethyl ether
• Dioxane
• Methyl isobutyl ether

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Chemical Hazards Classification

• Class D1
• Poisonous Infectious Materials
• Material causing immediate and serious toxic
  effects
• Materials which are potentially fatal or may
  cause permanent damage if inhaled, swallowed, or
  absorbed through the skin, or may burn the skin
  or eyes upon contact
• Cyanides, TEA salts

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Chemical Hazards Classification

• Class D2
• Poisonous Infectious Materials
• Material causing other chronic or long term
  effects
• Material which may cause death or permanent
  damage as a result of repeated exposure over an
  extended period of time may be an irritant to
  the skin, eyes, or respiratory system may cause
  cancer, birth defects, or sterility.
• Asbestose

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Chemical Hazards Classification

• Class D3
• Poisonous Infectious Materials
• Biohazardous and Infectious Materials
• Materials which may cause disease in humans and
  animals
• Viruses, bacteria, and fungi, cultures and
  diagnostic specimens such as blood, urine, and
  body tissue

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Chemical Hazards Classification

• Class E
• Corrosive Material
• Material which may corrode aluminum and steel or
  human flesh
• Material which are anhydrous corrosive gases
• Cause tissue damage and burns on contact with
  skin or eyes.
• Inorganic Acids and Bases

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Chemical Hazards Classification

• Inorganic Acids
• H2SO4, HNO3, HClO4, HCl
• Segregate from bases and organic compounds
• Store in a ventilated acid cabinet
• Know the location of eye washes and safety
  showers
• Store on lower shelves
• Never pour water into acid. Always add the acid
  to the water. Add acid slowly, with stirring

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Chemical Hazards Classification

• Hydrogen fluoride
• Is extremely corrosive
• Dissolves glass
• Absence of immediate pain, penetration can be
  extensive, leading to serious injury or death
• Causes severe eye irritation and skin burns

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Chemical Hazards Classification

• Bases
• NaOH, NH4OH
• Segregate from acids and organic compounds
• Store in a ventilated cabinet
• Know the location of eye washes and safety
  showers
• Store on lower shelves

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Chemical Hazards Classification

• Class F
• Dangerously Reactive Material
• Materials which undergo vigorous polymerization,
  condensation or decomposition Ethylene Oxide
• Materials which become self-reactive under
  conditions of increased temperature, pressure or
  shock Organic Azides
• Materials which react vigorously with water to
  produce a very hazardous gas Na, LiAlH4, CaH2.

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Chemical Hazards Classification

• Pyrophoric Materials
• Air reactive
• White phosphorus,
• diborane,
• diethyl aluminum chloride,
• lithium
• Store under an inert atmosphere such as nitrogen

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Chemical Hazards Classification

• Cryogenic Materials
• Never use to cool substances which are
  combustible in air. Explosion risk from
  condensation of oxygen from air
• Use insulated gloves and face shield
• Keep cryogenic substances in containers which are
  not tightly closed to prevent explosive pressure
  build-up
• Use only equipment designed for cryogenic
  materials
• Liquid Nitrogen

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Chemical Hazards Symbols

• Flammable
• Explosive
• Toxic/Poison

• Irritant
• Corrosive
• Environmental

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Chemical Hazard Symbols and Definitions

• Flammable Any substance that will burn if
  exposed to an open flame.
• Explosive A substance that may explode if
  exposed to heat or flame.

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Chemical Hazard Symbols and Definitions

• Toxic/Poison A substance that can lead to
  death if inhaled, ingested, or absorbed by the
  skin.
• Corrosive A substance that can destroy or
  burn living tissue and can eat away at other
  materials.

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Chemical Hazard Symbols and Definitions

• Irritant - A substance that causes
  inflammation upon contact with skin or mucous
  membranes.
• Environmental - Substances that are harmful to
  the environment. They must be disposed of
  properly, not washed down the drain.

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NFPA Hazard Identification
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So How Do I Need All This???