Chemical hazard
What is a Chemical Hazard?
Any chemical that can cause illness, injury, or an emergency.
Chemical Hazards
Physical
Health
Chemical health hazard
Irritants
Nephrotoxins
Corrosives
Hepatotoxins
Sensitizer
Neurotoxins
Target-Organ
Chemicals
Agents
which act
on the
blood
Reproductive
Agents
which
damage
the lungs
Carcinogens
Eye
hazards
Physical hazard
Explosive
Fire hazard
pyrophorics
oxidizers
flammable
Reactive chemicals
Combustibles
Water reactive
Unstable
Chemical Health Effects
Irritants: Inflame skin or eye tissues on contact.
Corrosives: Destroy skin tissue at point of contact.
Sensitizers: Cause allergic reactions in normal tissue after exposure.
Target-Organ Chemicals: Damage specific body organs and systems.
Reproductive Hazards: Change genetic information in egg or sperm
cells and/or damage fetus after conception.
Carcinogens: Cause cancer.
Irritants
.
Is the inflammation results from concentrations
low concentration (far below those needed to
cause corrosion).
Common irritants include substances such as:
1. ammonia
2. alkaline dusts and mists
3. epoxy resins
4. ozone
5. nitrogen dioxide
6. phosphorus chloride
2- Corrosive
Visible damage, or irreversible
damage to body tissue Acids
Caustics (or bases)
Hydrochloric acid, sulfuric acid,
nitric acid
Acids
1
pH Scale
7
Caustics
(or bases)
14
3-Target organ effect
1
Hepatotoxins
2
Nephrotoxins
3
Neurotoxins
4
Agents which act on the blood
5
Agents which damage the lungs
6
Eye hazards
1- Hepatotoxins
Chemicals which produce liver damage
Example : Carbon Tetrachloride, nitrosamines
2-Nephrotoxins
Chemicals which produce kidney damage
Examples: Halogenated Hydrocarbons, uranium
3- Neurotoxins
Chemicals which produce their primary
toxic effects on the nervous system
Examples: Mercury, carbon disulfide, lead
5- Agents which act on the blood
Decrease hemoglobin function, deprive the
body tissues of oxygen
Examples : Carbon monoxide, cyanides
6- Agents which damage the lungs
Chemicals which damage pulmonary tissue Signs and
Symptoms: Cough, tightness in the chest, loss of breath
Chemicals: Asbestos (Mg3Si2O5(OH)4), silica
Reproductive Hazards
• Chemicals which damage reproductive capabilities
• Includes chromosomal damage (mutations) and
damage to fetuses (teratogenesis)
• Signs and Symptoms: Birth defects, sterility
• Chemicals examples: Lead
Carcinogens
A “carcinogen” commonly refers to any agent that can
initiate or speed the development of malignant tumors
Carcinogens commonly used in significant quantities include
formaldehyde (Formalin solutions), benzene, ethylene oxide,
and chloroform.
physical health hazard
Fire hazard
Reactive chemicals
Explosive
Flammable hazarded material
• What are flammable and combustible liquids?
• Flammable and combustible liquids are present in
almost every workplace. Fuels and many common
products like solvents, thinners, cleaners,
adhesives, paints, waxes and polishes may be
flammable or combustible liquids
What is a flashpoint?
The flashpoint of a liquid is the lowest temperature at which the
liquid gives off enough vapors to be ignited (start burning)
Flammable Chemicals
• Examples: diethyl ether, acetone, hexanes, ethanol,
methanol
• flammability rating is given by a number 4-0 in
• flammability rating of diethyl ether is "4"
while acetone, methanol, ethanol, and hexanes are "3".
• Ether is extremely flammable and any spark or simply
heat can ignite it.
• flammable liquid have Flashing point <22.8 0C
• Combustibles liquid have Flashing point > 22.8 0C
flammable material Protection
• Never use ether in a lab that has an open
flame anywhere in the room.
• Be careful not to spill any flammable solvent
(especially ether) on a heating mantle or hot
plate.
• Keep them away from electrical outlets.
A pyrophoric
• A pyrophoric substance ignites spontaneously in air
at or below 55°C (130°F).Examples are iron sulfide
and White phosphorus
• They can be handled safely in atmospheres of
nitrogen.
• Most pyrophoric fires should be extinguished with
a Class D fire extinguisher for burning metals.
Explosives
• is a reactive substance that contains a great amount of
potential energy that can produce an explosion if released
suddenly,
• Nitroglycerin: A highly unstable and sensitive liquid.
• Acetone peroxide: A very unstable white organic peroxide.
• TNT: Yellow insensitive crystals that can be melted and cast
without detonation.
• Nitrocellulose: A nitrated polymer which can be a high or
low explosive depending on nitration level and conditions
•
Reactive chemicals
A water-reactive substance is one that
spontaneously undergoes a chemical reaction with
water. Notable examples include lithium, sodium,
potassium, rubidium, and caesium
Unstable hazard : Radioactive material
oxidizing agent hazard
• An oxidizing agent (also oxidant, oxidizer or
oxidizer) is the element or compound gaining
electrons (and is thus often called an electron
acceptor),
• Examples
• Oxygen (O2)
• Ozone (O3)
• Hydrogen peroxide (H2O2) and other inorganic
peroxides
• Fluorine (F2), chlorine (Cl2), and other halogens
What Should the Ideal Laboratory Look Like?
1.
2.
3.
4.
5.
6.
Equipment & Ventilation
Safety Showers and Eyewashes
Chemical Storage
Match the Extinguisher to the Risk!
Means of Egress/Exit
Material Safety Data Sheets(MSDS)
General Ventilation
Supply Air Diffusers & Room Air Exhausts Should be
Located So As to Avoid Intake of Contaminated Air
Windows Should be Operable
Local Ventilation
Fume Hoods Used For Operations that Give Off:
Noxious Odors
Flammable or Poisonous Vapors
2- Safety Showers and Eyewashes
Must Be Available in All Lab Areas That
Use or Store Chemicals Which Are
Corrosive or an Irritant to the Eyes or Skin
Combination Eye Wash & Drench Hose
Units at the Sink are Now Available
3- Chemical Storage
Safe Storage of Chemicals is a
Necessity in Every hospitals!
 Minimizes Exposure to Staff to Corrosive and
Toxic Chemicals
 Lessens the Risk of Fire
 Prevents the Mixing of Incompatibles & the
Creation of an Emergency Situation
The “Don’ts” of Chemical
Storage!
Avoid storing any chemical above eye level
Don’t store incompatible chemicals together
Don’t store chemicals near sources of heat or sunlight
Don’t store chemicals in the hoods or acids on metal
shelves
Avoid storing anything on the floor, especially glass
bottles
Ideal Storage Area Set-Up
Acids
Na, Li
Room Should Have:
•Eye Wash
bases
•Safety Shower
Oxidizers
Spill Materials
•Emergency Phone
•Fire Extinguisher
Dry Chemicals
Metal Salts
Flammables
Cabinet
Nitrates
4- Match the Extinguisher to the Risk
Class A fires involve organic solids such as
paper and wood.
A for "Ash"
Class B fires involve flammable or
combustible liquids, including petrol,
grease, and oil
B for "Barrel"
Class C fires involve electric current
C for "Current"
Class D fires involve combustible metals.
D for "Dynamite"
Oils and fats
K for "Kitchen
5- Means of Egress/ Exit
Two or more well- marked & unobstructed
evacuation exits are recommended in a lab.
6-Material Safety Data Sheets (MSDS)
• (MSDS) are one of the most important
tools
• available to employers
• for providing information, and protection
• to workers from hazardous chemicals
• which are used in the workplace.
Material Safety Data Sheets required
information
•
•
•
•
•
•
•
•
•
•
•
Identity of the chemical
Physical and chemical characteristics
Physical hazards
Chemical hazards
Primary routes of entry
exposure limits
Control measures
Emergency procedures
thechemical hazardous
Date of preparation
Name, address and telephone of the manufacturer
Be Prepared for Small Incidental Spills
Spills Chemical Categories
1- organic solvent
2- acids
3- bases
4- mercury
Proper Incidental Spill Control Equipment
Includes:
Examples of spill cleanup materials
include:
•
•
•
•
•
•
trisodium phosphate
sand
sodium bicarbonate for acids
powdered citric acid for bases
"Oil-Dri," "Zorb-All," "Speedi-Dri"
paper towels
Waste Chemical Disposal
Requires:
Proper storage– same rules apply – make sure waste
chemicals are compatible
Proper labeling – Containers containing hazardous waste
must be labeled with the words HAZARDOUS WASTE
Pre-planning – know what waste you’re creating
prior to carrying out experiments
Record-keeping – of all waste chemicals on hand
and those already picked up for disposal
• 1- Give the names of the two chemical hazards.
• 2. What name is given to a chemical which will
burst into flame when contacted by air?
• 3. What is a health hazard?
• 4. Which kind of health hazard destroys skin on
contact?
• 5. Chemicals that cause sterility, fetal death, and
birth defects are called ____________.
• 6. What is a carcinogen?
• 7. Give the three states in which a chemical can
exist.
• 8.What is an MSDS?
• 9.What kind of information is found on the MSDS?