1. Chemical Hazards
The overall objective for this
module is that participants will
extract and interpret chemical
hazard information from a Material
Safety Data Sheet
2. Overview
Chemical terms and definitions that will
help you when handling chemicals
General properties of common
chemicals and how to handle them
appropriately
How to use the Material Safety Data
Sheet to find information about a
chemical
3. Expectations
Identify three types of organic hydrocarbons
Identify the three major hazards associated with organic
compounds
List the three main types of inorganic chemicals
Identify the major hazard associated with inorganic
chemicals
Identify the two chemical types indicated on the pH scale
Identify a corrosive material based on the OSHA
definition
Use the Material Safety Data Sheet to find information
about a chemical
10. Hazards of Organic Chemicals
Most are flammable
• Characteristics such as flashpoints lower and
upper flammability and autoignition
temperatures should be known
Most are anesthetics
• They should always be used in well-ventilated
spaces
Some are carcinogens
• Toxicity limits should be known and appropriate
personal protective equipment worn
13. Identifying Acids
Acids have a pH less than 7
High concentration of H+ ions
Turn litmus paper red
Taste tart
React with metals to form hydrogen
gas
14. Identifying Bases
Bases have a pH greater than 7
Low concentration of H+ ions
Turn litmus paper blue
Taste bitter
Have a slippery, soapy feel
15. Identifying Salts
Salts are one or more metal ions
combined with one or more nonmetal
ions
Formed when an acid and base react
with one another
May be toxic and contain heavy
metals
16. Hazard of Inorganic
Chemicals
Corrosive
• The second most commonly used and
transported group of hazardous
materials.
• “Any liquid that has a severe corrosion
rate on steel”.
17. Hazard of Inorganic
Chemicals
Corrosive
OSHA Definition:
• “A chemical that causes visible
destruction of, or irreversible
alterations in, living tissue by
chemical action at the site of
contact.”
18. Properties of Chemicals
Physical properties - Can be measured
Chemical properties - How a chemical
will react
19. Physical Properties
Volatility
Boiling point
Vapor pressure
• Measure of pressure that a gas/vapor will exert
on the inside of a closed container
• Measured in mm of mercury or inches of
mercury
• As temperatures rise the vapor pressure
increases
20. Physical Properties
Evaporation rate
Melting / Freezing point
Specific gravity
• Water = 1
• Less than one is less dense and will
float in water
• More than one is more dense and will
sink in water
21. Physical Properties
Vapor Density
• When the gases and vapors are compared
to normal room air (air = 1)
• Any gas or vapor that has a number less
than one is less dense and will rise in air
• Any gas or vapor that has a number larger
than one is more dense and will sink in air
Solubility
Chemical Compatibility
22. Physical Properties
pH
• It is a scale
• Low and high numbers are corrosive
Flashpoint
• Minimum temperature at which a
substance gives off vapor sufficient to
form an ignitable mixture with air
23. Physical Properties
Flammable - Flashpoint below 1410 F
Combustible - Flashpoint above 1410 F
and below 2000 F
Ignitable - Flashpoint less than 1410 F
24. Physical Properties
Lower Flammable Limit (LFL or LEL) and
Upper Flammable Limit (UFL or UEL)
• Are the range of chemical vapor to air ratio
that needs to exist before a chemical will
ignite
25. Physical Properties
Lower Flammable Limit
• Lowest concentration, by volume in air,
which will explode, ignite, or burn when
there is an ignition source
Upper Flammable Limit
• Maximum concentration, by volume in
air, which will explode, ignite, or burn
when there is an ignition source
30. Water Reactive
Chemicals become spontaneously
flammable or give off flammable or
toxic gas when in contact with water
31. Chemical References
Material Safety Data Sheets
The Chemical Dictionary
Product Label
Farm Chemical Handbook
Poison Control Center
32. Material Safety Data Sheets
(MSDS)
OSHA Requirements
• Identity
• Physical and Chemical Characteristics
• Physical Hazards
• Health Hazards
• Routes of Entry
• PEL and TLV
33. OSHA Requirements
• Carcinogenicity
• Precautions for Safe Handling and Use
• Control Measures
• Emergency and First Aid Procedures
• Date of Preparation
• Name, Address, Phone Number of
Prepare
Material Safety Data Sheets
(MSDS)
34. Understanding types of chemicals,
properties, potential hazards, and use of
reference materials will enable you to
handle chemicals safely and
appropriately